Flu Vaccine 2017

Sunday, October 1, 2017 // Blog, Flu, Prevention, Vaccines

Information for 2017-2018

Getting an annual flu vaccine is the first and best way to protect yourself and your family from the flu. Flu vaccination can reduce flu illnesses, doctors’ visits, and missed work and school due to flu, as well as prevent flu-related hospitalizations. The more people who get vaccinated, the more people will be protected from flu, including older people, very young children, pregnant women and people with certain health conditions who are more vulnerable to serious flu complications. This page summarizes information for the 2017-2018 flu season.

What viruses will the 2017-2018 flu vaccines protect against?

There are many flu viruses, and they are constantly changing. The composition of U.S. flu vaccines is reviewed annually and updated to match circulating flu viruses. Flu vaccines protect against the three or four viruses that research suggests will be most common. For 2017-2018, three-component vaccines are recommended to contain:

  • an A/Michigan/45/2015 (H1N1)pdm09-like virus
  • an A/Hong Kong/4801/2014 (H3N2)-like virus
  • a B/Brisbane/60/2008-like (B/Victoria lineage) virus

Four-component vaccines, which protect against a second lineage of B viruses, are recommended to be produced using the same viruses recommended for the trivalent vaccines, as well as a B/Phuket/3073/2013-like (B/Yamagata lineage) virus.

We will be giving the Quadrivalent Flu Vaccine this fall.  A high dose vaccine will be available for those 65 and over.  It is marginally more effective and does not appear to have any greater risk of side effects.  If you have a scheduled appointment this fall, we will give it then.  Otherwise, you can call to schedule an appointment.  The optimal time is late October and early November.  Think pumpkins when thinking of the optimal time.  It is readily available, so if it is more convenient for you to get it at your pharmacy, work or school, it is fine to get it there.

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Words written in italic are directly from Mark L. Thornton, M.D., F.A.C.P.

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New Medicine/Old Medicine

Sunday, January 15, 2017 // Uncategorized

I haven’t blogged for awhile.  I haven’t been inspired.  Now I have just finished my  notes for Friday. It was a busy day and I left the office before I had finished all my documentation.  That happens often.  I get home and I spend another hour finishing notes.  This is the way it is with many doctors.  We want the record to reflect something of the patient encounter.  Too often, it is just documenting for reimbursement.  It’s about checking all the boxes necessary to meet certain core measures.  This article in The Annals of Internal Medicine’s section On Being a Doctor  captured the sense of  an older physician’s struggle to take care of patients while  teaching what medicine used to be like.

On Being a Doctor |6 December 2016

Coeur d’Alene

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Flu Shot Today? Later May Be Better Than Sooner

Sunday, September 18, 2016 // Uncategorized

This article is from Kaiser Health News.  It also was mentioned on NPR and The Rivard Report.  We’re still waiting on our quadrivalent vaccine to come in.  The pharmacies are 600 pound gorillas and get theirs first.  As this article mentions, it is best not to rush out and get it.

The Ads Say ‘Get Your Flu Shot Today,’ But It May Be Wiser To Wait

September 15, 2016

flu shot sign

The pharmacy chain pitches started in August: Come in and get your flu shot.

Convenience is touted. So are incentives: CVS offers a 20-percent-off shopping pass for everyone who gets a shot, while Walgreens donates toward international vaccination efforts.

The start of flu season is still weeks — if not months — away. Yet marketing of the vaccine has become an almost year-round effort, beginning when the shots become available in August and hyped as long as the supply lasts, often into April or May.

Not that long ago, most flu-shot campaigns started as the leaves began to turn in October. But the rise of retail medical clinics inside drug stores over the past decade — and state laws allowing pharmacists to give vaccinations — has stretched the flu-shot season.

The stores have figured out how “to deliver medical services in an on-demand way” which appeals to customers, particularly millennials, said Tom Charland, founder and CEO of Merchant Medicine, which tracks the walk-in clinic industry. “It’s a way to get people into the store to buy other things.”

But some experts say the marketing may be overtaking medical wisdom since it’s unclear how long the immunity imparted by the vaccine lasts, particularly in older people.

Federal health officials say it’s better to get the shot whenever you can. An early flu shot is better than no flu shot at all. But the science is mixed when it comes to how long a flu shot promoted and given during the waning days of summer will provide optimal protection, especially because flu season generally peaks in mid-winter or beyond. Experts are divided on how patients should respond to such offers.

“If you’re over 65, don’t get the flu vaccine in September. Or August. It’s a marketing scheme,” said Laura Haynes, an immunologist at the University of Connecticut Center on Aging.

That’s because a combination of factors makes it more difficult for the immune systems of people older than age 65 to respond to the vaccination in the first place. And its protective effects may wear off faster for this age group than it does for young people.

When is the best time to vaccinate? It’s a question even doctors have.

“Should I wait until October or November to vaccinate my elderly or medically frail patients?” That’s one of the queries on the website of the board that advises the Centers for Disease Control and Prevention on immunizations. The answer is that it is safe to make the shots available to all age groups when the vaccine becomes available, although it does include a caution.

The board says antibodies created by the vaccine decline in the months following vaccination “primarily affecting persons age 65 and older,” citing a study done during the 2011-2012 flu season. Still, while “delaying vaccination might permit greater immunity later in the season,” the CDC notes that “deferral could result in missed opportunities to vaccinate.”

How long will the immunity last?

“The data are very mixed,” said John J. Treanor, a vaccine expert at the University of Rochester medical school. Some studies suggest vaccines lose some protectiveness during the course of a single flu season. Flu activity generally starts in the fall, but peaks in January or February and can run into the spring.

“So some might worry that if [they] got vaccinated very early and flu didn’t show up until very late, it might not work as well,” he said.

But other studies “show you still have protection from the shot you got last year if it’s a year when the strains didn’t change,” Treanor said.

In any given flu season, vaccine effectiveness varies. One factor is how well the vaccines match the virus that is actually prevalent. Other factors influencing effectiveness include the age and general health of the recipient. In the overall population, the CDC says studies show vaccines can reduce the risk of flu by about 50 to 60 percent when the vaccines are well matched.

Health officials say it’s especially important to vaccinate children because they often spread the disease, are better able to develop antibodies from the vaccines and, if they don’t get sick, they won’t expose grandma and grandpa. While most people who get the flu recover, it is a serious disease responsible for many deaths each year, particularly among older adults and young children. Influenza’s intensity varies annually, with the CDC saying deaths associated with the flu have ranged from about 3,300 a year to 49,000 during the past 31 seasons.

To develop vaccines, manufacturers and scientists study what’s circulating in the Southern Hemisphere during its winter, which is our summer. Then — based on that evidence — forecast what flu strains might circulate here to make vaccines that are generally delivered in late July.

For the upcoming season, the vaccines will include three or four strains, including two A strains, an H1N1 and an H3N2, as well as one or two B strains, according to the CDC. It recommends that everyone older than 6 months get vaccinated, unless they have health conditions that would prevent it.

The vaccines can’t give a person the flu because the virus is killed before it’s included in the shot. This year, the nasal vaccine is not recommended for use, as studies showed it was not effective during several of the past flu seasons.

But when to go?

“The ideal time is between Halloween and Thanksgiving,” said Haynes at UConn. “If you can’t wait and the only chance is to get it in September, then go ahead and get it. It’s best to get it early rather than not at all.”

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Preventing Falls Among Older Adults

Friday, August 5, 2016 // Prevention



We all want to protect our older family members and help them stay safe, secure, and independent. Knowing how to reduce the risk of falling, a leading cause of injury, is a step toward this goal.

The Reality

Each year, one in every three adults ages 65 or older falls and 2 million are treated in emergency departments for fall-related injuries. And the risk of falling increases with each decade of life. The long-term consequences of fall injuries, such as hip fractures and traumatic brain injuries (TBI), can impact the health and independence of older adults. Thankfully, falls are not an inevitable part of aging. In fact, many falls can be prevented. Everyone can take actions to protect the older adults they care about.

Prevention Tips

You can play a role in preventing falls. Encourage the older adults in your life to:

  • Get some exercise. Lack of exercise can lead to weak legs and this increases the chances of falling. Exercise programs such as Tai Chi can increase strength and improve balance, making falls much less likely.
  • Be mindful of medications. Some medicines—or combinations of medicines—can have side effects such as dizziness or drowsiness. This can make falling more likely. Having a doctor or pharmacist review all medications can help reduce the chance of risky side effects and drug interactions.
  • vision
    Keep their vision sharp.
    Poor vision can make it harder to get around safely. Older adults should have their eyes checked every year and wear glasses or contact lenses with the right prescription strength to ensure they are seeing clearly.
  • Eliminate hazards at home. About half of all falls happen at home. A home safety check can help identify potential fall hazards that need to be removed or changed, such as tripping hazards, clutter, and poor lighting.

Steps for Home Safety

The following checklist can help older adults reduce their risk of falling at home:

  • Remove things you can trip over (such as papers, books, clothes, and shoes) from stairs and places where you walk.
  • Install handrails and lights on all staircases.
  • Remove small throw rugs or use double-sided tape to keep the rugs from slipping.
  • Keep items you use often in cabinets you can reach easily without using a step stool.
  • Put grab bars inside and next to the tub or shower and next to your toilet.
  • Use non-slip mats in the bathtub and on shower floors.
  • Improve the lighting in your home. As you get older, you need brighter lights to see well. Hang lightweight curtains or shades to reduce glare.
  • Wear shoes both inside and outside the house. Avoid going barefoot or wearing slippers.

More Information

CDC offers various materials and resources for all audiences about older adult falls and what can be done to prevent them. These resources are for the general public, public health officials, and anyone interested in programs that aim to prevent falls.


25th Year of Precepting

This marks my 25th year of serving as a community preceptor for medical students at the University of Texas Health Science Center at San Antonio.  My thanks to those patients who have taken time to meet with students.  Here is a comment from one of them:


The past 4 weeks with Dr. Thornton was probably one of my favorite rotations of 3rd year. There is an ample amount of diversity in the types of medical problems seen from routine follow ups to vaccinations needed for world travel as well as more chronic conditions. Dr. Thornton’s attentiveness and laid back personality make him a great instructor. He often provided me with articles he found interesting and we had many conversations about medicine and life in general. He really made me feel like I was part of the treatment team. His staff is extremely nice and personable. I feel very fortunate to have had this rotation.

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Protection against Mosquitoes, Ticks, & Other Arthropods

Friday, August 5, 2016 // Prevention

Roger S. Nasci, Robert A. Wirtz, William G. Brogdon

Vaccines or chemoprophylactic drugs are available to protect against some vectorborne diseases such as yellow fever, Japanese encephalitis, and malaria; however, travel health practitioners should advise travelers to use repellents and other general protective measures against biting arthropods. The effectiveness of malaria chemoprophylaxis is variable, depending on patterns of drug resistance, bioavailability, and compliance with medication, and no similar preventive measures exist for other mosquitoborne diseases such as dengue, chikungunya, Zika, and West Nile encephalitis or tickborne diseases such as Lyme borreliosis, tickborne encephalitis, and relapsing fever.

The Environmental Protection Agency (EPA) regulates repellent products in the United States. CDC recommends that consumers use repellent products that have been registered by EPA. EPA registration indicates the materials have been reviewed and approved for both efficacy and human safety when applied according to the instructions on the label.


Avoid outbreaks. To the extent possible, travelers should avoid known foci of epidemic disease transmission. The CDC Travelers’ Health website provides updates on regional disease transmission patterns and outbreaks (

Be aware of peak exposure times and places. Exposure to arthropod bites may be reduced if travelers modify their patterns or locations of activity. Although mosquitoes may bite at any time of day, peak biting activity for vectors of some diseases (such as dengue and chikungunya) is during daylight hours. Vectors of other diseases (such as malaria) are most active in twilight periods (dawn and dusk) or in the evening after dark. Avoiding the outdoors or taking preventive actions (such as using repellent) during peak biting hours may reduce risk. Place also matters; ticks and chiggers are often found in grasses, woodlands, or other vegetated areas. Local health officials or guides may be able to point out areas with increased arthropod activity.

Wear appropriate clothing. Travelers can minimize areas of exposed skin by wearing long-sleeved shirts, long pants, boots, and hats. Tucking in shirts, tucking pants into socks, and wearing closed shoes instead of sandals may reduce risk. Repellents or insecticides, such as permethrin, can be applied to clothing and gear for added protection. (Additional information on clothing is below.)

Check for ticks. Travelers should inspect themselves and their clothing for ticks during outdoor activity and at the end of the day. Prompt removal of attached ticks can prevent some infections. Showering within 2 hours of being in a tick-infested area reduces the risk of some tickborne diseases.

Bed nets. When accommodations are not adequately screened or air conditioned, bed nets are essential in providing protection and reducing discomfort caused by biting insects. If bed nets do not reach the floor, they should be tucked under mattresses. Bed nets are most effective when they are treated with a pyrethroid insecticide. Pretreated, long-lasting bed nets can be purchased before traveling, or nets can be treated after purchase. Effective, treated nets may also be available in destination countries. Nets treated with a pyrethroid insecticide will be effective for several months if they are not washed. Long-lasting pretreated nets may be effective for much longer.

Insecticides and spatial repellents. More spatial repellent products are becoming commercially available. These products, containing active ingredients such as metofluthrin and allethrin, augment aerosol insecticide sprays, vaporizing mats, and mosquito coils that have been available for some time. Such products can help to clear rooms or areas of mosquitoes (spray aerosols) or repel mosquitoes from a circumscribed area (coils, spatial repellents). Although many of these products appear to have repellent or insecticidal activity under particular conditions, they have not yet been adequately evaluated in peer-reviewed studies for their efficacy in preventing vectorborne disease. Travelers should supplement the use of these products with repellent on skin or clothing and using bed nets in areas where vectorborne diseases are a risk or biting arthropods are noted. Since some products available internationally may contain pesticides that are not registered in the United States, it may be preferable for travelers to bring their own. Insecticides and repellent products should always be used with caution, avoiding direct inhalation of spray or smoke.

Optimum protection can be provided by applying the repellents described in the following sections to clothing and to exposed skin (Box 2-03).

Box 2-03. Maximizing protection from mosquitoes and ticks

To optimize protection against mosquitoes and ticks and reduce the risk of diseases they transmit:

  • Wear a long-sleeved shirt, long pants, and socks.
  • Treat clothing with permethrin or purchase pretreated clothing.
    • Permethrin-treated clothing will retain repellent activity through multiple washes.
    • Repellents used on skin can also be applied to clothing but provide shorter duration of protection (same duration as on skin) and must be reapplied after laundering.
  • Apply lotion, liquid, or spray repellent to exposed skin.
  • For Mosquitoes
    • Ensure adequate protection during times of day when mosquitoes are most active.
    • Dengue, yellow fever, and chikungunya vector mosquitoes bite mainly from dawn to dusk.
    • Malaria, West Nile, and Japanese encephalitis vector mosquitoes bite mainly from dusk to dawn.
    • Use common sense. Reapply repellents as protection wanes and mosquitoes start to bite.
  • For Ticks
    • Check yourself daily (your entire body) and remove attached ticks promptly.


CDC has evaluated information published in peer-reviewed scientific literature and data available from EPA to identify several types of EPA-registered products that provide repellent activity sufficient to help people reduce the bites of disease-carrying mosquitoes. Products containing the following active ingredients typically provide reasonably long-lasting protection:

  • DEET (chemical name: N,N-diethyl-m-tolua-mide or N,N-diethyl-3-methyl-benzamide). Products containing DEET include, but are not limited to, Off!, Cutter, Sawyer, and Ultrathon.
  • Picaridin (KBR 3023 [Bayrepel] and icaridin outside the United States; chemical name: 2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methylpropyl ester). Products containing picaridin include, but are not limited to, Cutter Advanced, Skin So Soft Bug Guard Plus, and Autan (outside the United States).
  • Oil of lemon eucalyptus (OLE) or PMD (chemical name: para-menthane-3,8-diol), the synthesized version of OLE. Products containing OLE and PMD include, but are not limited to, Repel and Off! Botanicals. This recommendation refers to EPA-registered repellent products containing the active ingredient OLE (or PMD). “Pure” oil of lemon eucalyptus (essential oil not formulated as a repellent) is not recommended; it has not undergone similar, validated testing for safety and efficacy, is not registered with EPA as an insect repellent, and is not covered by this recommendation.
  • IR3535 (chemical name: 3-[N-butyl-N-acetyl]-aminopropionic acid, ethyl ester). Products containing IR3535 include, but are not limited to, Skin So Soft Bug Guard Plus Expedition and SkinSmart.

EPA characterizes the active ingredients DEET and picaridin as “conventional repellents” and OLE, PMD, and IR3535 as “biopesticide repellents,” which are either derived from or are synthetic versions of natural materials.

Repellent Efficacy

Published data indicate that repellent efficacy and duration of protection vary considerably among products and among mosquito and tick species. Product efficacy and duration of protection are also markedly affected by ambient temperature, level of activity, amount of perspiration, exposure to water, abrasive removal, and other factors. In general, higher concentrations of active ingredient provide longer duration of protection, regardless of the active ingredient. Products with <10% active ingredient may offer only limited protection, often 1–2 hours. Products that offer sustained-release or controlled-release (microencapsulated) formulations, even with lower active ingredient concentrations, may provide longer protection times. Studies suggest that concentrations of DEET above approximately 50% do not offer a marked increase in protection time against mosquitoes; DEET efficacy tends to plateau at a concentration of approximately 50%. CDC recommends using products with ≥20% DEET on exposed skin to reduce biting by ticks that may spread disease.

Recommendations are based on peer-reviewed journal articles and scientific studies and data submitted to regulatory agencies. People may experience some variation in protection from different products. Regardless of what product is used, if travelers start to get insect bites they should reapply the repellent according to the label instructions, try a different product, or, if possible, leave the area with biting insects.

Ideally, repellents should be purchased before traveling and can be found online or in hardware stores, drug stores, and supermarkets. A wide variety of repellents can be found in camping, sporting goods, and military surplus stores. When purchasing repellents overseas, look for the active ingredients specified above on the product labels; some names of products available internationally have been specified in the list above.

Repellency Awareness Graphic

The Environmental Protection Agency (EPA) allows companies to apply for permission to include a new repellency awareness graphic on the labels of insect repellents that are applied to the skin (Figure 2-01( The graphic helps consumers easily identify the time a repellent is effective against mosquitoes and ticks. EPA reviews products that apply to use the graphic to ensure that their data meet current testing protocols and standard evaluation practices. Use of this graphic by manufacturers is voluntary. For more information, visit

Repellents and Sunscreen

Repellents that are applied according to label instructions may be used with sunscreen with no reduction in repellent activity; however, limited data show a one-third decrease in the sun protection factor (SPF) of sunscreens when DEET-containing insect repellents are used after a sunscreen is applied. Products that combine sunscreen and repellent are not recommended, because sunscreen may need to be reapplied more often and in larger amounts than needed for the repellent component to provide protection from biting insects. In general, the recommendation is to use separate products, applying sunscreen first and then applying the repellent. Due to the decrease in SPF when using a DEET-containing insect repellent after applying sunscreen, travelers may need to reapply the sunscreen more frequently.

Repellents and Insecticides for Use on Clothing

Clothing, hats, shoes, bed nets, jackets, and camping gear can be treated with permethrin for added protection. Products such as Permanone and Sawyer, Permethrin, Repel, and Ultrathon Permethrin Clothing Treatment are registered with EPA specifically for use by consumers to treat clothing and gear. Alternatively, clothing pretreated with permethrin is commercially available, marketed to consumers in the United States as Insect Shield, BugsAway, or Insect Blocker.

Permethrin is a highly effective insecticide-acaricide and repellent. Permethrin-treated clothing repels and kills ticks, chiggers, mosquitoes, and other biting and nuisance arthropods. Clothing and other items must be treated 24–48 hours in advance of travel to allow them to dry. As with all pesticides, follow the label instructions when using permethrin clothing treatments.

Permethrin-treated materials retain repellency or insecticidal activity after repeated laundering but should be retreated, as described on the product label, to provide continued protection. Clothing that is treated before purchase is labeled for efficacy through 70 launderings. Clothing treated with the other repellent products described above (such as DEET) provides protection from biting arthropods but will not last through washing and will require more frequent reapplications.

Precautions when Using Insect Repellents

Travelers should take the following precautions:

  • Apply repellents only to exposed skin or clothing, as directed on the product label. Do not apply repellents under clothing.
  • Never use repellents over cuts, wounds, or irritated skin.
  • When using sprays, do not spray directly on face—spray on hands first and then apply to face. Do not apply repellents to eyes or mouth, and apply sparingly around ears.
  • Wash hands after application to avoid accidental exposure to eyes or ingestion.
  • Children should not handle repellents. Instead, adults should apply repellents to their own hands first, and then gently spread on the child’s exposed skin. Avoid applying directly to children’s hands. After returning indoors, wash your child’s treated skin and clothing with soap and water or give the child a bath.
  • Use just enough repellent to cover exposed skin or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, apply a bit more.
  • After returning indoors, wash repellent-treated skin with soap and water or bathe. Wash treated clothing before wearing it again. This precaution may vary with different repellents—check the product label.

If a traveler experiences a rash or other reaction, such as itching or swelling, from an insect repellent, the repellent should be washed off with mild soap and water and its use discontinued. If a severe reaction has occurred, a local poison-control center should be called for further guidance, if feasible. Travelers seeking health care because of the repellent should take the repellent to the doctor’s office and show the doctor. Permethrin should never be applied to skin but only to clothing, bed nets, or other fabrics as directed on the product label.

Children and Pregnant Women

Most repellents can be used on children aged >2 months. Protect infants aged <2 months from mosquitoes by using an infant carrier draped with mosquito netting with an elastic edge for a tight fit. Products containing OLE specify that they should not be used on children aged <3 years. Other than the safety tips listed above, EPA does not recommend any additional precautions for using registered repellents on children or on pregnant or lactating women.

Useful Links


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There has been a recent resurgence in bedbug infestations worldwide, particularly in developed countries. Although bedbugs do not transmit diseases, their bites may be a nuisance. Travelers can take measures to avoid bedbug bites and avoid transporting them in luggage and clothing (Box 2-04).

Box 2-04. Bedbugs and international travel

A recent resurgence in bedbug infestations worldwide, particularly in developed countries, is thought to be related to the increase in international travel, pest control strategy changes in travel lodgings, and insecticide resistance. Bedbug infestations have been increasingly reported in hotels, theaters, and any locations where people congregate, even in the workplace, dormitories, and schools. Bedbugs may be transported in luggage and on clothing. Transport of personal belongings in contaminated transport vehicles is another means of spread of these insects.

Bedbugs are small, flat insects that are reddish-brown in color, wingless, and range from 1 to 7 mm in length. Although bedbugs have not been shown to transmit disease, their bites can produce strong allergic reactions and considerable emotional stress.

Protective Measures against Bedbugs

Travelers should be encouraged to take the following precautions to avoid or reduce their exposure to bedbugs:

  • Inspect the premises of hotels or other sleeping locations for bedbugs on mattresses, box springs, bedding, and furniture, particularly built-in furniture with the bed, desk, and closets as a continuous structural unit. Travelers who observe evidence of bedbug activity—whether it be the bugs themselves or physical signs such as blood-spotting on linens—should seek alternative lodging.
  • Keep suitcases closed when they are not in use and try to keep them off the floor.
  • Remove clothing and personal items (such as toiletry bags and shaving kits) from the suitcase only when they are in use.
  • Carefully inspect clothing and personal items before returning them to the suitcase.
  • Keep in mind that bedbug eggs and nymphs are very small and can be easily overlooked.

Prevention is by far the most effective and inexpensive way to protect oneself from these pests. The costs of ridding a personal residence of these insects are considerable, and efforts at control are often not immediately successful even when conducted by professionals.


  1. Barnard DR, Xue RD. Laboratory evaluation of mosquito repellents against Aedes albopictus, Culex nigripalpus, and Ochlerotatus triseriatus (Diptera: Culicidae). J Med Entomol. 2004 Jul;41(4):726–30.
  2. Fradin MS, Day JF. Comparative efficacy of insect repellents against mosquito bites. N Engl J Med. 2002 Jul 4;347(1):13–8.
  3. Goodyer LI, Croft AM, Frances SP, Hill N, Moore SJ, Onyango SP, et al. Expert review of the evidence base for arthropod bite avoidance. J Travel Med. 2010 May–Jun;17(3):182–92.
  4. Lupi E, Hatz C, Schlagenhauf P. The efficacy of repellents against Aedes, Anopheles, Culex and Ixodes—a literature review. Travel Med Infect Dis. 2013 Nov–Dec;11(6):374–411.
  5. Montemarano AD, Gupta RK, Burge JR, Klein K. Insect repellents and the efficacy of sunscreens. Lancet. 1997 Jun 7;349(9066):1670–1.
  6. Murphy ME, Montemarano AD, Debboun M, Gupta R. The effect of sunscreen on the efficacy of insect repellent: a clinical trial. J Am Acad Dermatol. 2000 Aug;43(2 Pt 1):219–22.
  7. Pages F, Dautel H, Duvallet G, Kahl O, de Gentile L, Boulanger N. Tick repellents for human use: prevention of tick bites and tick-borne diseases. Vector Borne Zoonotic Dis. 2014 Feb;14(2):85–93.
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Injury Prevention

Friday, August 5, 2016 // Prevention

David A. Sleet, David J. Ederer, Michael F. Ballesteros

According to the World Health Organization (WHO), injuries are among the leading causes of death and disability in the world, and they are the leading cause of preventable death in travelers. Among travelers, data show that injuries are one of the leading causes for consulting a physician, hospitalization, repatriation, and death. Worldwide, injuries are the leading cause of death for young people aged 15–29 years. Estimates have reported that 18%–24% of deaths among travelers in foreign countries are caused by injuries. Infectious diseases accounted for only 2% of deaths to travelers abroad. Contributing to the injury toll while traveling are exposure to unfamiliar and perhaps risky environments, differences in language and communications, less stringent product safety and vehicle standards, unfamiliar rules and regulations, a carefree holiday or vacation spirit leading to more risk-taking behavior, and overreliance on travel and tour operators to protect one’s safety and security.

From 2011 through 2013, an estimated 2,466 US citizens died from non-natural causes, such as injuries and violence, while in foreign countries (excluding deaths occurring in the wars in Iraq and Afghanistan). Motor vehicle crashes—not crime or terrorism—are the number 1 killer of healthy US citizens living, working, or traveling in foreign countries. From 2011 through 2013, 621 Americans died in road traffic crashes abroad (25% of all non-natural deaths to US citizens abroad). Another 555 were victims of homicide (23%), 392 committed suicide (16%), and 309 were victims of drowning (13%) (Figure 2-02( Other less common but serious injuries are related to natural disasters, aviation accidents, drugs, terrorism, falls, burns, and poisoning.

If a traveler is seriously injured, emergency care may not be available or acceptable by US standards. Trauma centers capable of providing optimal care for serious injuries are uncommon outside urban areas in many foreign destinations. Travelers should be aware of the increased risk of certain injuries while traveling or residing abroad, particularly in developing countries, and be prepared to take preventive steps.


Globally, an estimated 3,300 people are killed each day, including 720 children, in road traffic crashes involving cars, buses, motorcycles, bicycles, trucks, and pedestrians. Annually, 1.24 million are killed and 20–50 million are injured in traffic crashes—a number likely to double by 2030. Although only 53% of the world’s vehicles are in developing countries, >90% of road traffic casualties occur in these countries.

International efforts to combat road deaths command a tiny fraction of the resources deployed to fight diseases such as malaria and tuberculosis, yet the burden of road traffic injuries is comparable. In response to this crisis, in March 2010 the 64th General Assembly of the United Nations described the global road safety crisis as “a major public health problem” and proclaimed 2011–2020 as “The Decade of Action for Road Safety.” On April 19, 2012, the United Nations General Assembly adopted a new resolution (A/66/PV.106) to improve global road safety by implementing plans for the decade, setting ambitious targets, and monitoring global road traffic fatalities.

According to Department of State data, road traffic crashes are the leading cause of injury deaths to US citizens while abroad (Figure 2-02( Of the 621 US citizens killed in road traffic crashes from 2011 through 2013, approximately 110 (18%) deaths involved motorcycles. Unlike in the United States, in many countries, 2- and 3-wheeled vehicles outnumber cars, and travelers unfamiliar with driving or riding motorcycles may be at higher risk of crashing. Most non-natural American deaths in Thailand and Vietnam, popular travel destinations, were related to motorcycle use. Motorcycle use is also dangerous for travelers in countries where motorcycles are not the primary mode of transportation. The reported rate of motorbike injuries in Bermuda is much higher in tourists than in the local population, and the rate is highest in people aged 50–59 years. Motor vehicle rentals in Bermuda and some other small Caribbean islands are typically limited to motorbikes for tourists, possibly contributing to the higher rates of motorbike injuries. Loss of vehicular control, unfamiliar equipment, and inexperience with motorized 2-wheelers contributed to crashes and injuries, even at speeds <30 miles per hour.

Road traffic crashes are common among foreign travelers for a number of reasons: lack of familiarity with the roads, driving on the opposite side of the road, lack of seat belt use, the influence of alcohol, poorly made or maintained vehicles, travel fatigue, poor road surfaces without shoulders, unprotected curves and cliffs, and poor visibility due to lack of adequate lighting. In many developing countries, unsafe roads and vehicles and an inadequate transportation infrastructure contribute to the traffic injury problem. In many of these countries, motor vehicles often share the road with vulnerable road users, such as pedestrians, bicyclists, and motorcycle users. The mix of traffic involving cars, buses, taxis, rickshaws, large trucks, and even animals increases the risk for crashes and injuries.

Millions of US citizens travel to Mexico each year, and >150,000 people cross the US–Mexico border daily. Travelers should be particularly cautious in Mexico; from 2011 through 2013, 27% of all deaths of US citizens abroad occurred in that country, where >200 Americans died in road traffic crashes.

Strategies to reduce the risk of traffic injury are shown in Table 2-12( The Association for International Road Travel ( and Make Roads Safe ( have useful safety information for international travelers, including road safety checklists and country-specific driving risks. The Department of State has safety information useful to international travelers, including road safety and security alerts, international driving permits, and travel insurance (

Figure 2-02. Leading causes of injury death for US citizens in foreign countries, 2011-20131,2


View Larger Figure

1Data from US Department of State. Death of US citizens abroad by non-natural causes. Washington, DC: US Department of State; 2014 [cited 2014 March 26]. Available from:

2Excludes deaths of US citizens fighting wars in Afghanistan or Iraq, and deaths that were not reported to the nearest US embassy or consulate.


Table 2-12. Recommended strategies to reduce injuries while abroad

Road Traffic Crashes
Lack of seat belts and child safety seats Always use safety belts and child safety seats. Rent vehicles with seat belts; when possible, ride in taxis with seat belts and sit in the rear seat; bring child safety seats and booster seats from home for children to ride properly restrained.
Driving hazards When possible, avoid driving at night in developing countries; always pay close attention to the correct side of the road when driving in countries that drive on the left.
Country-specific driving hazards Check the Association for Safe International Road Travel website for driving hazards or risks by country (
Motorcycles, motor bikes, and bicycles Always wear helmets (bring a helmet from home, if needed). When possible, avoid driving or riding on motorcycles or motorbikes, including motocycle and motorbike taxis. Traveling overseas is a bad time to learn to drive a motorcycle or motorbike.
Alcohol-impaired driving Alcohol increases the risk for all causes of injury. Do not drive after consuming alcohol, and avoid riding with someone who has been drinking.
Cellular telephones Do not use a cellular telephone or text while driving. Many countries have enacted laws banning cellular telephone use while driving, and some countries have made using any kind of telephone, including hands-free, illegal while driving.
Taxis or hired drivers Ride only in marked taxis, and try to ride in those that have safety belts accessible. Hire drivers familiar with the area.
Bus travel Avoid riding in overcrowded, overweight, or top-heavy buses or minivans.
Pedestrian hazards Be alert when crossing streets, especially in countries where motorists drive on the left side of the road. Walk with a companion or someone from the host country.
Other Tips
Airplane travel Avoid using local, unscheduled aircraft. If possible, fly on larger planes (>30 seats), in good weather, during the daylight hours, and with experienced pilots. Children <2 years should sit in a child safety seat, not on a parent’s lap. Whenever possible, parents should travel with a safety seat for use before, during, and after a plane ride.
Drowning Avoid swimming alone or in unfamiliar waters. Wear life jackets while boating or during water recreation activities.
Burns In hotels, stay below the sixth floor to maximize the likelihood of being rescued in case of a fire. Bring your own smoke alarm.



Drowning accounts for 13% of all deaths of US citizens abroad. Although risk factors have not been clearly defined, these deaths are most likely related to unfamiliarity with local water currents and conditions, inability to swim, and the absence of lifeguards on duty. Rip currents can be especially dangerous, as are sea animals such as urchins, jellyfish, coral, and sea lice. Alcohol also contributes to drowning and boating mishaps.

Drowning was the leading cause of injury death to US citizens visiting countries where water recreation is a major activity, such as Fiji, the Bahamas, Jamaica, and Costa Rica. Young men are particularly at risk of head and spinal cord injuries from diving into shallow water, and alcohol is a factor in some cases.

Boating can be a hazard, especially if boaters are unfamiliar with the boat, do not know proper boating etiquette or rules for watercraft navigation, or are new to the water environment in a foreign country. From 2011 through 2013, maritime accidents accounted for 8% of deaths to healthy Americans abroad. Many boating fatalities result from inexperience or failure to wear lifejackets.

Scuba diving is a frequent pursuit of travelers in coastal destinations. The death rate among all divers worldwide is thought to be 15–20 deaths per 100,000 divers per year. Travelers should either be experienced divers or dive with a reliable dive shop and instructors. See the Scuba Diving( section later in this chapter for a more detailed discussion about diving risks and preventive measures.


From 2011 through 2013, aviation incidents, drug-related incidents, and deaths classified as “other unintentional injuries” accounted for 22% of deaths to healthy US citizens abroad (Figure 2-02( Fires can be a substantial risk in developing countries where building codes do not exist or are not enforced, there are no smoke alarms, there is no access to emergency services, and the fire department’s focus is on putting out fires rather than on fire prevention or victim rescue.

Travel by local, lightweight aircraft in many countries can be risky. From 2011 through 2013, an estimated 82 US citizens abroad were killed in aircraft crashes. Travel on unscheduled flights, in small aircraft, at night, in inclement weather, and with inexperienced pilots carries the highest risk.

Before flying with children, parents and caregivers should check to make sure that their child restraint system is approved for use on an aircraft. This approval should be printed on the system’s information label or on the device itself. The Federal Aviation Administration (FAA) recommends that a child weighing <20 lb use a rear-facing child restraint system. A forward-facing child safety seat should be used for children weighing 20–40 lb. FAA has also approved a harness-type device for children weighing 22–44 lb.

Travel health providers, vendors of travel services, and travelers themselves should consider the following:

  • Purchasing special travel health and medical evacuation insurance if their destinations include countries where there may not be access to good medical care (see the Travel Insurance, Travel Health Insurance, & Medical Evacuation Insurance section later in this chapter).
  • Because trauma care is poor in many countries, victims of injuries and violence can die before reaching a hospital, and there may be no coordinated ambulance service available. In remote areas, medical assistance and modern drugs may be unavailable, and travel to the nearest medical facility can take a long time.
  • Adventure activities, such as mountain climbing, skydiving, whitewater rafting, dune-buggying, and kayaking, are popular with travelers. The lack of rapid emergency trauma response, inadequate trauma care in remote locations, and sudden, unexpected weather changes that compromise safety and hamper rescue efforts can delay access to care.
  • Travelers should avoid using local, unscheduled, small aircraft. If available, choose larger aircraft (>30 seats), as they are more likely to have undergone more strict and regular safety inspections. Larger aircraft also provide more protection in the event of a crash. For country-specific airline crash events, see
  • When traveling by air with young children, consider bringing a child safety seat approved for use on an aircraft.
  • To prevent fire-related injuries, travelers should select accommodations no higher than the sixth floor. (Fire ladders generally cannot reach higher than the sixth floor.) Hotels should be checked for smoke alarms and preferably sprinkler systems. Travelers may want to bring their own smoke alarm. Two escape routes from buildings should always be identified. Crawling low under smoke and covering one’s mouth with a wet cloth are helpful in escaping a fire. Families should agree on a meeting place outside the building in case a fire erupts.
  • Improperly vented heating devices may cause poisoning from carbon monoxide. Carbon monoxide at the back of boats near the engine can be especially dangerous. Travelers may want to carry a personal detector that can sound an alert in the presence of this lethal gas.
  • Travelers should consider learning basic first aid and CPR before travel overseas with another person. Travelers should bring a travel health kit, which should be customized to the anticipated itinerary and activities (see the Travel Health Kits section later in this chapter).
  • Suicide is the third-leading cause of injury death to US citizens abroad, accounting for 16% of non-natural deaths. For longer-term travelers (such as missionaries and volunteers), social isolation and substance abuse, particularly while living in areas of poverty and rigid gender roles, may increase the risk of depression and suicide. See the Mental Health( section later in this chapter for more detailed information.


  1. Ball DJ, Machin N. Foreign travel and the risk of harm. Int J Inj Contr Saf Promot. 2006 Jun;13(2):107–15.
  2. Cortes LM, Hargarten SW, Hennes HM. Recommendations for water safety and drowning prevention for travelers. J Travel Med. 2006 Jan–Feb;13(1):21–34.
  3. FIA Foundation for the Automobile and Society. Make roads safe report: a decade of action for road safety. FIA Foundation for the Automobile and Society; 2009 [cited 2014 Aug 8]. Available from:
  4. Guse CE, Cortes LM, Hargarten SW, Hennes HM. Fatal injuries of US citizens abroad. J Travel Med. 2007 Sep–Oct;14(5):279–87.
  5. Krug EG, Mercy JA, Dahlberg LL, Zwi AB. The world report on violence and health. Lancet. 2002 Oct 5;360(9339):1083–8.
  6. Lawson CJ, Dykewicz CA, Molinari NA, Lipman H, Alvarado-Ramy F. Deaths in international travelers arriving in the United States, July 1, 2005 to June 30, 2008. J Travel Med. 2012 Mar–Apr;19(2):96–103.
  7. Leggat PA, Fischer PR. Accidents and repatriation. Travel Med Infect Dis. 2006 May–Jul;4(3–4):135–46.
  8. McInnes RJ, Williamson LM, Morrison A. Unintentional injury during foreign travel: a review. J Travel Med. 2002 Nov–Dec;9(6):297–307.
  9. Sleet DA, Balaban V. Travel medicine: preventing injuries to children. Am J Lifestyle Med. 2013 Mar 10;7(2):121–9.
  10. World Health Organization. WHO global status report on road safety 2013: supporting a decade of action Geneva: World Health Organization; 2013 [cited 2014 Sep 19]. Available from:
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Fats, Fat and Death

Sunday, July 24, 2016 // Uncategorized

Here are a couple of recent articles dealing with the type of a fat in the diet and mortality and obesity and mortality.

Being Modestly Overweight Linked to Increased All-Cause Mortality Risk

By Amy Orciari Herman

Edited by Susan Sadoughi, MD, and Richard Saitz, MD, MPH, FACP, FASAM

Being even modestly overweight is associated with increased mortality risk, according to a large meta-analysis in the Lancet. The finding calls into question prior research suggesting that a slightly elevated body-mass index might be protective.

Researchers examined individual participant data from 189 studies comprising nearly four million adults who had never smoked, had no known chronic conditions at baseline, and survived beyond 5 years of follow-up. Participants were from North America, Europe, Australia, and East Asia.

Overall, roughly 386,000 participants died. All-cause mortality was lowest at a BMI of 20.0–24.9 (normal weight) and then increased significantly and linearly beginning at a BMI of 25.0–27.4 (hazard ratio, 1.07). BMIs below 20.0 also posed increased risk. The findings were consistent across geographic regions, and associations between higher BMIs and mortality were greater in younger than older participants and in men than in women.

The authors write, “These findings suggest that if the overweight and obese population had WHO-defined normal levels of BMI, the proportion of premature deaths that could be avoided would be about one in five in North America.”

Dr. Harlan Krumholz of NEJM Journal Watch Cardiology commented: “What I really want to know is not average risk, but who has the most risk, if any, among those who are modestly overweight. Meanwhile, as a physician, my greatest emphasis regarding weight loss will remain on those with marked elevation of BMI, those with the highest risk.”

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Overuse of Antibiotics

Thursday, May 5, 2016 // Uncategorized

Antibiotics are often prescribed for upper respiratory tract infections inappropriately.  According to the most recent study, 1/3 of antibiotics are prescribed inappropriately.  Overuse of antibiotics leads to resistance of bacteria.  Here is a summary of a recent JAMA article from Physicians First Watch.  Following that is the American College of Physicians informational page for patients on appropriate antibiotic use.

May 5, 2016 Population-Based Estimates of Appropriate and Inappropriate Antibiotic Prescribing Thomas L. Schwenk, MD reviewing Fleming-Dutra KE et al. JAMA 2016 May 3. Tamma PD and Cosgrove SE. JAMA 2016 May 3. Thomas L. Schwenk, MDThe U.S. annual antibiotic prescribing rate in 2010 was about 500 prescriptions per 1000 people; one third of prescriptions were judged to be inappropriate. Thomas L. Schwenk, MDResearch about inappropriate antibiotic prescribing usually focuses on specific conditions and age groups. However, these researchers used several national ambulatory care databases to provide overall population-based estimates that could guide government and professional mandates designed to reduce inappropriate antibiotic prescribing.Researchers assessed appropriateness of antibiotic use in about 184,000 ambulatory visits (not including urgent care centers, “minute” clinics, federal facilities, or long-term care facilities) in 2010 and 2011 using accepted clinical practice guidelines. If guidelines were not available (e.g., for sinusitis), the lowest regional level of antibiotic use was used as a surrogate for appropriateness (almost certainly still an overestimate). For some conditions (e.g., pneumonia), all antibiotic use was deemed to be appropriate.The overall annual rate of antibiotic use was 506 prescriptions per 1000 people, of which roughly two thirds of prescriptions (353 prescriptions/1000 people) were deemed to be appropriate. The overall rate ranged from 423 to 553 prescriptions per 1000 people in the West and South, respectively. Most inappropriate antibiotic use was for acute respiratory conditions (111 prescriptions/1000 people annually).Comment – See more at:

Appropriate Antibiotic Use for Acute Respiratory Tract Infection in Adults: Advice for High-Value Care From the American College of Physicians and the Centers for Disease Control and Prevention

 What are acute respiratory tract infections?

Acute respiratory tract infections (ARTIs) are common in adults. ARTIs include bronchitis, sinus infections, sore throat, and the common cold. Most are caused by a virus, not by bacteria.

What are harms related to antibiotic use?

Antibiotics are medicines used to treat illnesses that are caused by bacteria, such as strep throat (medical name: group A streptococcal pharyngitis) or pneumonia. Antibiotics will not work for illnesses caused by viruses, such as the common cold. Antibiotics can cause harm when they are not used the right way. These harms can include:

Side effects: These can be mild, such as upset stomach, diarrhea, or skin rash. However, in some cases they can be very serious and even life-threatening.

High costs: Prescriptions that are not needed increase patients’ out-of-pocket costs. It is estimated that 50% of antibiotic prescriptions are not needed, totaling more than $3 billion in wasted spending.

Antibiotic resistance: When antibiotics are used when they are not needed, germs and bacteria can become resistant to them. This means that common antibiotics will not be able to treat certain illnesses. Antibiotic-resistant bacteria cause more serious illnesses that are harder to cure and can be life-threatening.

Why are so many people prescribed antibiotics when they are not needed?

Because antibiotics have often been used when not needed, many patients expect to receive antibiotics for ARTIs and believe that they need them to feel better. In other cases, clinicians may prescribe antibiotics right away, rather than waiting or testing to see if they are needed.

How did the ACP develop this advice?

The authors looked at research and clinical guidelines related to antibiotic use for ARTIs. This information was used to develop advice for clinicians and patients.

What does the ACP recommend that patients and physicians do?

Reducing unneeded antibiotic prescribing will improve care, lower costs, and help to stop antibiotic resistance. In most patients, symptoms get better in 1 to 2 weeks. Coughs can sometimes last up to 6 weeks. The ACP recommends the following:

•Clinicians should not prescribe antibiotics for patients with bronchitis. Antibiotics should only be used if patients have pneumonia.

•Clinicians should test patients with symptoms that could be strep throat. Because symptoms alone are not reliable, antibiotics should only be prescribed when testing confirms strep throat. Other sore throat infections do not need antibiotics.

•Clinicians should not prescribe antibiotics for sinus infections unless patients have severe symptoms or symptoms that last more than 10 days. Patients whose symptoms improve but eventually get worse may also need antibiotics.

•Clinicians should not prescribe antibiotics for patients with the common cold.

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The Benefits of Quitting Smoking

Wednesday, March 2, 2016 // Uncategorized

It’s never too late.  From a recent review article on smoking cessation from the Annals of Internal Medicine. Even patients who have lung cancer have an average survival that is longer in those who quit smoking than those who continue to smoke.

The benefits of quitting begin immediately and last for decades. After 10 years of smoking cessation, the risk for lung cancer in former smokers was reduced up to 50% (1). Smoking cessation reduces risk for death from CAD by two thirds within 2–3 years of quitting, with risk approaching that of persons who have never smoked (12, 13). Circulation improves within weeks of quitting, and stroke risk is reduced to the level of that of nonsmokers in 2–4 years (14). Lung function improves within 3 months. Smoking cessation during the first 3–4 months of pregnancy reduces risk for low birthweight to that of never-smokers. Other benefits include reduced damaging effects on skin, breath, teeth and gums, smell, and taste. Finally, smokers and providers should be aware that tobacco use can affect metabolism of caffeine and commonly prescribed medications, including olanzapine, clozapine, and theophylline (15). Therefore, when smokers successfully quit, medication doses might be lowered.

Health Benefits of Quitting Tobacco

Symptoms: Minutes–days: Lower BP; lower carbon monoxide; better stamina, smell, tasteLung function

  • 2–4 weeks: Decreased respiratory infections

  • 4–12 weeks: Improved lung function

Cardiovascular disease

  • 2–3 months: Improved circulation

  • 1 year: 50% reduction for heart attack

  • 5–15 years: Cardiovascular risk equals that of never-smokers

Cancer: 10 years: Risk for lung cancer reduced by half

Is there an age after which smoking cessation no longer yields benefit?
Smoking cessation benefits people of all ages, regardless of smoking history (6, 7). Older smokers, despite smoking for many years, may have increased motivation from health concerns and symptoms of tobacco-related illness, experience with what has been successful in past quit attempts, and better access to treatment resources.
Two large, recent, retrospective cohort analyses showed that smokers who quit at age 55–64 years gained 4 years of life and that even those who quit after age 70 years had lower risk for mortality than those who continued to smoke (6, 7).
Clinical Bottom Line: Health Consequences of Smoking
Tobacco use affects nearly every organ system in the body and leads to numerous disorders, including heart disease, stroke, many types of cancer, vascular disease, respiratory infections, diabetes, and gastroesophageal reflux disease. The health benefits of quitting start within minutes and continue for years. These risk-reduction benefits are especially significant for smokers with CAD, COPD, or those who are pregnant by reducing preterm labor and low birthweight. Cessation for smokers with children can reduce exposure to and disease caused by environmental tobacco smoke. Even after decades of smoking, those who stop smoking significantly reduce their risk for death from certain diseases, such as lung cancer, and slow the deterioration of lung function in patients with COPD. One is never too old or young, too healthy or sick, to benefit from smoking cessation.
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“I Heard This on TV….”

Tuesday, February 23, 2016 // Uncategorized

We are constantly bombarded with medical news. It is part of the fodder of the news media.  The problem with this is that information is not all of the same caliber. It doesn’t all carry the same weight. Case in point, a recent study showed and association between proton pump inhibitors like Nexium and chronic kidney disease.  This is a summary from Journal Watch.

  • Proton-Pump Inhibitors Are Associated with Chronic Kidney Disease Thomas L. Schwenk, MD reviewing Lazarus B et al. JAMA Intern Med 2016 Jan 11. Schoenfeld AJ and Grady D. JAMA Intern Med 2016 Jan 11. Thomas L. Schwenk, MDA further reason to use PPIs only when their clinical benefits are clear Thomas L. Schwenk, MD Polypharmacy is one possible cause of the increasing prevalence of chronic kidney disease (CKD) in the U.S. population. Proton-pump inhibitor (PPI) use is associated with acute renal injury, but PPIs also have other biological effects, including hypomagnesemia, that can lead to excess risk for CKD. In a population-based, prospective cohort study, researchers followed 10,482 adults (mean age, 63; 80% white) with normal renal function (estimated glomerular filtration rate, >60 mL/minute/1.73 m2); at baseline, 322 participants used PPIs and 956 participants used histamine-2 (H2)–receptor antagonists. During the study (median follow-up, 14 years), PPI use increased markedly, to ≈27% of participants.At study end, the unadjusted incidence of CKD was significantly higher among baseline-PPI users than among baseline nonusers (14.2 vs. 10.7 cases per 1000 person-years); after statistical adjustment, the difference remained significant (hazard ratio, 1.5). CKD risk for baseline H2–antagonist users remained at baseline levels. A similar replication study in 249,000 participants who were followed for a median 6 years yielded similar results.Comment:These results add to increasing concerns about PPI use, including excess risks for Clostridium difficile infections, pneumonia, and fractures. Editorialists recommend monitoring renal function and magnesium levels in patients who are taking PPIs and who are at high risk for CKD; such patients should switch to H2-antagonists when possible and should not use PPIs for vague complaints of heartburn or dyspepsia. – See more at:


    The problem is that observational studies have inherent weaknesses. The following is from Wikepedia.

    Observational study

    From Wikipedia, the free encyclopedia

    Jump to: navigation, search

    In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample to a population where the independent variable is not under the control of the researcher because of ethical concerns or logistical constraints. One common observational study is about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator.[1][2] This is in contrast with experiments, such as randomized controlled trials, where each subject is randomly assigned to a treated group or a control group.



    The independent variable may be beyond the control of the investigator for a variety of reasons:

    • A randomized experiment would violate ethical standards. Suppose one wanted to investigate the abortion – breast cancer hypothesis, which postulates a causal link between induced abortion and the incidence of breast cancer. In a hypothetical controlled experiment, one would start with a large subject pool of pregnant women and divide them randomly into a treatment group (receiving induced abortions) and a control group (not receiving abortions), and then conduct regular cancer screenings for women from both groups. Needless to say, such an experiment would run counter to common ethical principles. (It would also suffer from various confounds and sources of bias, e.g.,it would be impossible to conduct it as a blind experiment.) The published studies investigating the abortion–breast cancer hypothesis generally start with a group of women who already have received abortions. Membership in this “treated” group is not controlled by the investigator: the group is formed after the “treatment” has been assigned.[citation needed]
    • The investigator may simply lack the requisite influence. Suppose a scientist wants to study the public health effects of a community-wide ban on smoking in public indoor areas. In a controlled experiment, the investigator would randomly pick a set of communities to be in the treatment group. However, it is typically up to each community and/or its legislature to enact a smoking ban. The investigator can be expected to lack the political power to cause precisely those communities in the randomly selected treatment group to pass a smoking ban. In an observational study, the investigator would typically start with a treatment group consisting of those communities where a smoking ban is already in effect.[citation needed]
    • A randomized experiment may be impractical. Suppose a researcher wants to study the suspected link between a certain medication and a very rare group of symptoms arising as a side effect. Setting aside any ethical considerations, a randomized experiment would be impractical because of the rarity of the effect. There may not be a subject pool large enough for the symptoms to be observed in at least one treated subject. An observational study would typically start with a group of symptomatic subjects and work backwards to find those who were given the medication and later developed the symptoms. Thus a subset of the treated group was determined based on the presence of symptoms, instead of by random assignment.

    Types of observational studies

    • Case-control study: study originally developed in epidemiology, in which two existing groups differing in outcome are identified and compared on the basis of some supposed causal attribute.
    • Cross-sectional study: involves data collection from a population, or a representative subset, at one specific point in time.
    • Longitudinal study: correlational research study that involves repeated observations of the same variables over long periods of time.
    • Cohort study or Panel study: a particular form of longitudinal study where a group of patients is closely monitored over a span of time.
    • Ecological study: an observational study in which at least one variable is measured at the group level.

    Degree of usefulness and reliability

    Although observational studies cannot be used as reliable sources to make statements of fact about the “safety, efficacy, or effectiveness” of a practice,[3] they can still be of use for some other things:

    “[T]hey can: 1) provide information on “real world” use and practice; 2) detect signals about the benefits and risks of…[the] use [of practices] in the general population; 3) help formulate hypotheses to be tested in subsequent experiments; 4) provide part of the community-level data needed to design more informative pragmatic clinical trials; and 5) inform clinical practice.”[3]

    Bias and compensating methods

    In all of those cases, if a randomized experiment cannot be carried out, the alternative line of investigation suffers from the problem that the decision of which subjects receive the treatment is not entirely random and thus is a potential source of bias. A major challenge in conducting observational studies is to draw inferences that are acceptably free from influences by overt biases, as well as to assess the influence of potential hidden biases.

    An observer of an uncontrolled experiment (or process) records potential factors and the data output: the goal is to determine the effects of the factors. Sometimes the recorded factors may not be directly causing the differences in the output. There may be more important factors which were not recorded but are, in fact, causal. Also, recorded or unrecorded factors may be correlated which may yield incorrect conclusions. Finally, as the number of recorded factors increases, the likelihood increases that at least one of the recorded factors will be highly correlated with the data output simply by chance.

    In lieu of experimental control, multivariate statistical techniques allow the approximation of experimental control with statistical control, which accounts for the influences of observed factors that might influence a cause-and-effect relationship. In healthcare and the social sciences, investigators may use matching to compare units that nonrandomly received the treatment and control. One common approach is to use propensity score matching in order to reduce confounding.[4]

    A report from the Cochrane Collaboration in 2014 came to the conclusion that observational studies are very similar in results reported by similarly conducted randomized controlled trials. In other words, it reported little evidence for significant effect estimate differences between observational studies and randomized controlled trials, regardless of specific observational study design, heterogeneity, or inclusion of studies of pharmacological interventions. It therefore recommended that factors other than study design per se need to be considered when exploring reasons for a lack of agreement between results of randomized controlled trials and observational studies.[5]

    In 2007, several prominent medical researchers issued the Strengthening the reporting of observational studies in epidemiology (STROBE) statement, in which they called for observational studies to conform to 22 criteria that would make their conclusions easier to understand and generalise.[6]

    Correlation does not imply causation” is a phrase used in statistics to emphasize that a correlation between two variables does not imply that one causes the other.[1][2] Many statistical tests calculate correlation between variables. A few go further, using correlation as a basis for testing a hypothesis of a true causal relationship; examples are the Granger causality test and convergent cross mapping.[clarification needed (hypothesis testing not well explained here)]

    The counter-assumption, that “correlation proves causation”, is considered a questionable cause logical fallacy in that two events occurring together are taken to have a cause-and-effect relationship. This fallacy is also known as cum hoc ergo propter hoc, Latin for “with this, therefore because of this”, and “false cause”. A similar fallacy, that an event that follows another was necessarily a consequence of the first event, is sometimes described as post hoc ergo propter hoc (Latin for “after this, therefore because of this”).

    For example, in a widely studied case, numerous epidemiological studies showed that women taking combined hormone replacement therapy (HRT) also had a lower-than-average incidence of coronary heart disease (CHD), leading doctors to propose that HRT was protective against CHD. But randomized controlled trials showed that HRT caused a small but statistically significant increase in risk of CHD. Re-analysis of the data from the epidemiological studies showed that women undertaking HRT were more likely to be from higher socio-economic groups (ABC1), with better-than-average diet and exercise regimens. The use of HRT and decreased incidence of coronary heart disease were coincident effects of a common cause (i.e. the benefits associated with a higher socioeconomic status), rather than a direct cause and effect, as had been supposed.[3]

    As with any logical fallacy, identifying that the reasoning behind an argument is flawed does not imply that the resulting conclusion is false. In the instance above, if the trials had found that hormone replacement therapy does in fact have a negative incidence on the likelihood of coronary heart disease the assumption of causality would have been correct, although the logic behind the assumption would still have been flawed.

    BOTTOM LINE: I don’t know if proton pump inhibitors cause kidney disease just like I don’t know if calcium supplements cause heart disease or statins cause ALS. All of these have been implicated in previous observational studies.  I do know that all medication should be used cautiously and not indiscriminately. It is worthwhile to periodically review the drugs that your are taking and discuss with your physician if they should be continued.



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