Archive for September, 2011

Prediction of Erectile Function After Treatment for Prostate Cancer

Tuesday, September 27, 2011 // Uncategorized

When men are diagnosed with prostate cancer, they face the prospect of treatments that have substantial side effects.  the biggest concerns are urinary incontinence and erectile dyfunction.  Here is a summary of an article that appears in the current issue of JAMA (Journal of the American Medical Association). The study compares the risk of erectile dysfunction with surgery, external radiation and radioactive seeds which are a form of internal radiation. Following that I have the abstract of the article.

Model predicts erectile function after prostate cancer

Researchers have developed a new model to predict the risk of erectile dysfunction for men undergoing prostate cancer treatment.

The model was developed using pre- and post-treatment data for more than 1,000 men who had prostatectomy, external radiotherapy or brachytherapy for prostate cancer at one of several academic medical centers between 2003 and 2006. The model’s ability to predict erectile dysfunction two years after treatment was then validated in a community-based cohort of almost 2,000 men. The results were published in the Sept. 21 Journal of the American Medical Association.

Two years after treatment, post-treatment erections were reported by 37% of the overall patient group (95% CI, 34% to 40%) and 48% of the men who had functional erections before treatment (95% CI, 45% to 52%). Of those men who were potent before treatment, erectile dysfunction was reported posttreatment in 60% of the prostatectomy group (95% CI, 55% to 65%), 42% of the external radiotherapy group (95% CI, 33% to 51%) and 37% of the brachytherapy group (95% CI, 30% to 45%).

The researchers identified several factors in addition to the method of treatment that appeared to affect the rate of posttreatment dysfunction, including pretreatment function (measured by a sexual health-related quality-of-life score), age, serum prostate-specific antigen (PSA) level, race/ethnicity, and body mass index. The model’s predictions of erectile function ranged from 10% to 70% depending on individual patient characteristics. The validation cohort indicated that the model performed well at predicting dysfunction.

The study also looked at the treatments men used to assist with erectile function. Phosphodiesterase-5 inhibitors were the most commonly used, and intracorporal penile injections were the least used but the most effective. Due to limitations of the observational design of the study, the results should be used not to determine treatment superiority, but rather to help set physicians’ and patients’ expectations after prostate cancer treatment, the authors said.

An accompanying editorial noted that the study was also limited by its failure to include men who chose watchful waiting over active surveillance and by the development of the model at academic medical centers, which may have better results.

After cautioning that the findings should be used cautiously, the editorialist offered a informal synopsis: “[F]or most scenarios, the take-away message is that if the patient has chosen surgery, he will more than likely lose erectile function, whereas if he has chosen radiotherapy, he has a better than even chance of preserving it, at least for 2 years.”

Original Contribution
JAMA. 2011;306(11):1205-1214. doi: 10.1001/jama.2011.1333

Prediction of Erectile Function Following Treatment for Prostate Cancer

  1. Mehrdad Alemozaffar, MD;
  2. Meredith M. Regan, ScD;
  3. Matthew R. Cooperberg, MD, MPH;
  4. John T. Wei, MD;
  5. Jeff M. Michalski, MD;
  6. Howard M. Sandler, MD;
  7. Larry Hembroff, PhD;
  8. Natalia Sadetsky, PhD;
  9. Christopher S. Saigal, MD, MPH;
  10. Mark S. Litwin, MD, MPH;
  11. Eric Klein, MD;
  12. Adam S. Kibel, MD;
  13. Daniel A. Hamstra, MD;
  14. Louis L. Pisters, MD;
  15. Deborah A. Kuban, MD;
  16. Irving D. Kaplan, MD;
  17. David P. Wood, MD;
  18. Jay Ciezki, MD;
  19. Rodney L. Dunn, MS;
  20. Peter R. Carroll, MD, MPH;
  21. Martin G. Sanda, MD

[+] Author Affiliations

  1. Author Affiliations: Urology Division (Drs Alemozaffar and Sanda) and Radiation Oncology Department (Dr Kaplan), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts; Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute and Harvard Medical School (Dr Regan); Department of Urology, University of California, San Francisco (Drs Cooperberg, Sadetsky, and Carroll); Departments of Urology (Drs Wei and Wood) and Radiation Oncology (Dr Hamstra) and Biostatistics Core (Mr Dunn), School of Medicine, University of Michigan, Ann Arbor; Departments of Radiation Oncology (Dr Michalski) and Surgery (Dr Kibel), Washington University, St Louis, Missouri; Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (Dr Sandler); Office for Survey Research, Institute for Public Policy and Social Research, Michigan State University, East Lansing (Dr Hembroff); Departments of Urology (Drs Saigal and Litwin) and Health Services (Dr Litwin), UCLA Center for Health Sciences, Los Angeles; Glickman Urological and Kidney Institute (Dr Klein) and Department of Radiation Oncology (Dr Ciezki), Cleveland Clinic Hospitals, Cleveland, Ohio; and Departments of Urology (Dr Pisters) and Radiation Oncology (Dr Kuban), M.D. Anderson Cancer Center, Houston, Texas.


Context Sexual function is the health-related quality of life (HRQOL) domain most commonly impaired after prostate cancer treatment; however, validated tools to enable personalized prediction of erectile dysfunction after prostate cancer treatment are lacking.

Objective To predict long-term erectile function following prostate cancer treatment based on individual patient and treatment characteristics.

Design Pretreatment patient characteristics, sexual HRQOL, and treatment details measured in a longitudinal academic multicenter cohort (Prostate Cancer Outcomes and Satisfaction With Treatment Quality Assessment; enrolled from 2003 through 2006), were used to develop models predicting erectile function 2 years after treatment. A community-based cohort (community-based Cancer of the Prostate Strategic Urologic Research Endeavor [CaPSURE]; enrolled 1995 through 2007) externally validated model performance. Patients in US academic and community-based practices whose HRQOL was measured pretreatment (N = 1201) underwent follow-up after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer. Sexual outcomes among men completing 2 years’ follow-up (n = 1027) were used to develop models predicting erectile function that were externally validated among 1913 patients in a community-based cohort.

Main Outcome Measures Patient-reported functional erections suitable for intercourse 2 years following prostate cancer treatment.

Results Two years after prostate cancer treatment, 368 (37% [95% CI, 34%-40%]) of all patients and 335 (48% [95% CI, 45%-52%]) of those with functional erections prior to treatment reported functional erections; 531 (53% [95% CI, 50%-56%]) of patients without penile prostheses reported use of medications or other devices for erectile dysfunction. Pretreatment sexual HRQOL score, age, serum prostate-specific antigen level, race/ethnicity, body mass index, and intended treatment details were associated with functional erections 2 years after treatment. Multivariable logistic regression models predicting erectile function estimated 2-year function probabilities from as low as 10% or less to as high as 70% or greater depending on the individual’s pretreatment patient characteristics and treatment details. The models performed well in predicting erections in external validation among CaPSURE cohort patients (areas under the receiver operating characteristic curve, 0.77 [95% CI, 0.74-0.80] for prostatectomy; 0.87 [95% CI, 0.80-0.94] for external radiotherapy; and 0.90 [95% CI, 0.85-0.95] for brachytherapy).

Conclusion Stratification by pretreatment patient characteristics and treatment details enables prediction of erectile function 2 years after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer.

0 Comments Read more

Your Medical Mind

Wednesday, September 21, 2011 // Uncategorized

I haven’t read this book, but I have read one by one half of the team, Jerome Groopman, M.D. called How Doctors Think.  I heard the authors interviewed today on NPR and what they said resonated with me.  The following is an article based on the interview.  It points out some of pitfalls of best practices and “cookbook” medicine.  Many of yesterday’s quality indicators are dropped within several years when they are proven wrong.  Now politicians are proposing that we pay for quality, but trying to determine what is quality care is elusive.


 Becoming Mindful Of Medical Decision Making


September 21, 2011





At the drugstore.

EnlargeSean Locke/ 


At the drugstore.


September 21, 2011

Whether making life-or-death decisions — or simply choosing a drug — we’re flooded with information and conflicting advice. Doctors, the media, statistics, guidelines, family members and Internet strangers can all weigh in on the best medications to take or the most effective treatment options.

So how do you pick the best one?

“There is no one right answer for everyone,” says Harvard Medical School oncologist Jerome Groopman. “But it’s very important for people to understand how the information applies to them as individuals and then to understand … their own personal approach to making choices … so that they’re confident that what they chose is right for them.”

Groopman and Pamela Hartzband, an endocrinologist at Harvard Medical School, have teamed up to write Your Medical Mind, a guidebook for patients trying to sift through medical choices and make the best decisions for themselves and their family members.

Your Medical Mind



Your Medical Mind

How to Decide What Is Right for You

by Jerome Groopman and Pamela Hartzband

Hardcover, 308 pages | purchase

Believers and Doubters

Groopman and Hartzband say most patients generally fall into two categories: believers and doubters.

“The believers are convinced that there’s a good solution to their problem and they just want to go for it. Sometimes they are believers in technology, sometimes they are believers in more natural remedies, but they believe,” says Hartzband. “And the doubters are people who are always skeptical, worrying about side effects, worried about risks and that maybe the treatment will be worse than the disease.”

Recognizing where someone lies on that spectrum is helpful for both patients and their physicians, says Hartzband.

“Understanding why a patient wants something or doesn’t want something really helps you lead them to the best possible choice,” she says. “It helps patients understand where you [as the physician] are coming from and vice versa.”

Patients who fall into the doubter category may worry about whether prescribed medications are necessary, which could lead to noncompliance with a doctor’s orders. Hartzband says that more than a third of all people do not currently fill their prescriptions or take their newly prescribed medications. Other patients fill the prescription and take the medication — but ask not to know about potential side effects. This can also be dangerous, says Groopman.

“I want to make sure if the patient’s feeling something, he or she is alert to it so that I can intervene as early as possible to prevent it from spiraling out of control,” he says. “If a patient says, ‘I want to take the drugs but I don’t want to know about any side effects,’ I say, ‘Let’s backtrack a little and see what’s important for you to know, because I want to make sure you’re getting the best and safest care.’ ”


The Limits Of Best Practices

Sometimes getting the best and safest care also means realizing that guidelines or “best practices” aren’t engraved in stone, says Groopman. He explains that best practices, which have become more common in recent years, come from experts who designate a course of treatment for patients with certain conditions, based on evidence and scientific studies. For instance, many hospitals now instruct residents and attending physicians to give aspirin to people with chest pain and symptoms of a heart attack.

“That kind of [emergency] medicine is amenable to standardization and best practices because it really doesn’t involve patient choice,” says Groopman. ” … But what’s happened, we believe, is that many of these expert committees have overreached. And they’re trying to make [medicine] one size fits all and dictate that every diabetic is treated [the same] way or every woman with breast cancer should be treated [the same way].”

Treating the patient as an individual — and not as a statistic or algorithm to be solved — is vitally important, says Groopman, because the best and safest care might not always be standardized.


“If you step back, you can have different groups of experts coming out with different best practices,” he says. “And what that tells you is that there is no right answer when you move into this gray zone of medicine.”

From an analysis of 100 best practices put together by committees in internal medicine, Groopman and Hartzband discovered that 14 percent were contradicted within a year. Within two years, a quarter of the best practices were contradicted, and by five years, almost half of the rules were overturned.

This is not to say that guidelines aren’t useful, says Hartzband. She emphasizes that she and Groopman are not “anti-guidelines.”

“Guidelines have an enormous amount of very useful information, and I think they can be extremely helpful,” she says. “But they shouldn’t be applied in a blanket way without thinking about the individual patient.”

Dr. Jerome Groopman is the Dina and Raphael Recanati Chair of Medicine at Harvard Medical School. He is also a staff writer for The New Yorker in medicine and biology and the author of several books, including The Anatomy of Hope and How Doctors Think. Dr. Pamela Hartzband is a faculty member at Beth Israel Deaconess Medical Center, Division of Endocrinology, and Harvard Medical School. She specializes in disorders of the thyroid and adrenal glands, and writes a bimonthly column with her husband, Groopman, for ACP Internist.


0 Comments Read more

LIfestyle Modification Helps Erectile Dysfunction

Wednesday, September 14, 2011 // Uncategorized

Men often worry that taking cholesterol lowering medication or blood pressure medication will cause erectile dysfunction.  This can be a side effect of some older medications, but this recent study outlined in Journal Watch details how treating the risk factors for heart disease with lifestyle modification and medication can improve erectile function.

 Treating Cardiovascular Risk Factors Can Improve Sexual Function in Men with ED

Using lifestyle modification or drug therapy to treat cardiovascular risk factors can ameliorate erectile dysfunction, according to a meta-analysis in the Archives of Internal Medicine.
The meta-analysis included four randomized trials that looked at the effects of lifestyle modification (e.g., weight loss, exercise) and two trials that examined the impact of atorvastatin on CV risk factors and erectile dysfunction. Some 740 men were included, and follow-up ranged from 2 to 24 months.
Overall, reducing CV risk factors with either lifestyle changes or statin therapy was associated with statistically significant improvements in sexual function. The benefits persisted even when patients were also using phosphodiesterase type 5 inhibitors (e.g., sildenafil).
The researchers write: “Erectile dysfunction detection in the primary health clinic may provide an opportunity for early adoption of a healthy lifestyle to improve the overall health of men.”

Here is the abstract from The Archives of Internal Medicine:

The Effect of Lifestyle Modification and Cardiovascular Risk Factor Reduction on Erectile Dysfunction

A Systematic Review and Meta-analysis

Bhanu P. Gupta, MD; M. Hassan Murad, MD; Marisa M. Clifton, MD; Larry Prokop, MLS; Ajay Nehra, MD; Stephen L. Kopecky, MD

Arch Intern Med. Published online September 12, 2011. doi:10.1001/archinternmed.2011.440

Background  Erectile dysfunction (ED) shares similar modifiablerisks factors with coronary artery disease (CAD). Lifestylemodification that targets CAD risk factors may also lead toimprovement in ED. We conducted a systematic review and meta-analysisof randomized controlled trials evaluating the effect of lifestyleinterventions and pharmacotherapy for cardiovascular (CV) riskfactors on the severity of ED.

Methods  A comprehensive search of multiple electronic database through August 2010 was conducted using predefined criteria. We included randomized controlled clinical trials with follow-up of at least 6 weeks of lifestyle modification intervention or pharmacotherapy for CV risk factor reduction.Studies were selected by 2 independent reviewers. The main outcome  measure of the study is the weighted mean differences in the International Index of Erectile Dysfunction (IIEF-5) score with95% confidence intervals (CIs) using a random effects model.

Results  A total of 740 participants from 6 clinical trials in 4 countries were identified. Lifestyle modifications and pharmacotherapy for CV risk factors were associated with statistically significant improvement in sexual function (IIEF-5 score): weighted mean difference, 2.66 (95% CI, 1.86-3.47). If the trials     intervention (n = 143) are excluded, the remaining4 trials of lifestyle modification interventions (n = 597)demonstrate statistically significant improvement in sexual function: weighted mean difference, 2.40 (95% CI, 1.19-3.61).

Conclusion  The results of our study further strengthen the evidence that lifestyle modification and pharmacotherapy for CV risk factors are effective in improving sexual function in men with ED.

Interventions that are good for the heart are good for the brain and for erectile function.  Another reason to eat right, exercise and,  if necessary, take medication.

0 Comments Read more

How Much Exercise Do You Need?

Thursday, September 8, 2011 // Uncategorized

I thought I would review what the recommended physical activity for adults should be.  From the Center for Disease Control”s website.  typically we think of the CDC as helping to prevent infectious disease, but the burden of non infectious disease such as diabetes and heart disease are increasing.

How much physical activity do adults need?

Physical activity is anything that gets your body moving. According to the 2008 Physical Activity Guidelines for Americans, you need to do two types of physical activity each week to improve your health–aerobic and muscle-strengthening.

For Important Health Benefits

Adults need at least:

walking 2 hours and 30 minutes (150 minutes) of moderate-intensity aerobic activity (i.e., brisk walking) every week and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).
jogging 1 hour and 15 minutes (75 minutes) of vigorous-intensity aerobic activity (i.e., jogging or running) every week and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).
walking jogging An equivalent mix of moderate- and vigorous-intensity aerobic activity and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).

Need more help with the guidelines?
Watch this video:
Physical Activity Guidelines Introduction Video Audio/Video file
Windows Media Player, 4:43
More videos


10 minutes at a time is fine

We know 150 minutes each week sounds like a lot of time, but you don’t have to do it all at once. Not only is it best to spread your activity out during the week, but you can break it up into smaller chunks of time during the day. As long as you’re doing your activity at a moderate or vigorous effort for at least 10 minutes at a time.

Give it a try

Try going for a 10-minute brisk walk, 3 times a day, 5 days a week. This will give you a total of 150 minutes of moderate-intensity activity.


For Even Greater Health Benefits

Adults should increase their activity to:

jogging 5 hours (300 minutes) each week of moderate-intensity aerobic activity and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).
jogging 2 hours and 30 minutes (150 minutes) each week of vigrous-intensity aerobic activity and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).
walking jogging An equivalent mix of moderate- and vigorous-intensity aerobic activity and
weight training muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest,  shoulders, and arms).

More time equals more health benefits
If you go beyond 300 minutes a week of moderate-intensity activity, or 150 minutes a week of vigorous-intensity activity, you’ll gain even more health benefits.


For more help with what counts as aerobic activity, watch this video:Aerobic activity - what counts? video Audio/Video file Windows Media Player, 4:48
More videos


Aerobic activity – what counts?

Aerobic activity or “cardio” gets you breathing harder and your heart beating faster. From pushing a lawn mower, to taking a dance class, to biking to the store – all types of activities count. As long as you’re doing them at a moderate or vigorous intensity for at least 10 minutes at a time.

Intensity is how hard your body is working during aerobic activity.

How do you know if you’re doing light, moderate, or vigorous intensity aerobic activities?
For most people, light daily activities such as shopping, cooking, or doing the laundry doesn’t count toward the guidelines. Why? Your body isn’t working hard enough to get your heart rate up.

Moderate-intensity aerobic activity means you’re working hard enough to raise your heart rate and break a sweat. One way to tell is that you’ll be able to talk, but not sing the words to your favorite song. Here are some examples of activities that require moderate effort:

  • Walking fast
  • Doing water aerobics
  • Riding a bike on level ground or with few hills
  • Playing doubles tennis
  • Pushing a lawn mower

Build up over time
If you want to do more vigorous-level activities, slowly replace those that take moderate effort like brisk walking, with more vigorous activities like jogging.


Vigorous-intensity aerobic activity means you’re breathing hard and fast, and your heart rate has gone up quite a bit. If you’re working at this level, you won’t be able to say more than a few words without pausing for a breath. Here are some examples of activities that require vigorous effort:

  • Jogging or running
  • Swimming laps
  • Riding a bike fast or on hills
  • Playing singles tennis
  • Playing basketball

You can do moderate- or vigorous-intensity aerobic activity, or a mix of the two each week. A rule of thumb is that 1 minute of vigorous-intensity activity is about the same as 2 minutes of moderate-intensity activity.

Some people like to do vigorous types of activity because it gives them about the same health benefits in half the time. If you haven’t been very active lately, increase your activity level slowly. You need to feel comfortable doing moderate-intensity activities before you move on to more vigorous ones. The guidelines are about doing physical activity that is right for you.

For more examples, see Measuring Physical Activity.


Muscle-strengthening activities – what counts?

woman using weight machineBesides aerobic activity, you need to do things to strengthen your muscles at least 2 days a week. These activities should work all the major muscle groups of your body (legs, hips, back, chest, abdomen, shoulders, and arms).

To gain health benefits, muscle-strengthening activities need to be done to the point where it’s hard for you to do another repetition without help.  A repetition is one complete movement of an activity, like lifting a weight or doing a sit-up.  Try to do 8—12 repetitions per activity that count as 1 set. Try to do at least 1 set of muscle-strengthening activities, but to gain even more benefits, do 2 or 3 sets.


videoMore videos
Learn how to strengthen your muscles
at home
in the gym

Muscle strengthening at the gym 


You can do activities that strengthen your muscles on the same or different days that you do aerobic activity, whatever works best. Just keep in mind that muscle-strengthening activities don’t count toward your aerobic activity total.

There are many ways you can strengthen your muscles, whether it’s at home or the gym. You may want to try the following:

  • Lifting weights
  • Working with resistance bands
  • Doing exercises that use your body weight for resistance (i.e., push ups, sit ups)
  • Heavy gardening (i.e., digging, shoveling)
  • Yoga

What if you have a disability?

If you are an adult with a disability, regular physical activity can provide you with important health benefits, like a stronger heart, lungs, and muscles, improved mental health, and a better ability to do everyday tasks. It’s best to talk with your health care provider before you begin a physical activity routine. Try to get advice from a professional with experience in physical activity and disability. They can tell you more about the amounts and types of physical activity that are appropriate for you and your abilities. If you are looking for additional information, visit The National Center on Physical Activity and DisabilityExternal Web Site Icon.


Tips on Getting Active

Adding Physical Activity to Your Life
If you’re thinking, “How can I meet the guidelines each week?” don’t worry. You’ll be surprised by the variety of activities you have to choose from.

Be Active Your Way: A Guide for AdultsBe Active Your Way: A Guide for AdultsExternal Web Site Icon
Based on the 2008 Physical Activity Guidelines for Americans, this brochure can help you decide the number of days, types of activities, and times that fit your schedule.

0 Comments Read more

Exercise: Even a Little is of Benefit

Tuesday, September 6, 2011 // Uncategorized

Sometimes people are daunted by the amount of exercise that is recommended:

  This study fromThe  Lancet indicates that even 15 minutes a day of exercise can have health benefits.  The first is the summary from Journal Watch followed by the abstract from The  Lancet.

Minimal Physical Activity Confers Mortality Benefit

Just 15 minutes of exercise daily lowered 8-year mortality and cancer incidence.

Current guidelines recommend 150 minutes weekly of leisure-time physical activity (LTPA) to achieve a variety of health benefits, but the benefits of less exercise are uncertain. Investigators in Taiwan studied a cohort of more than 400,000 healthy people who participated in a privately operated medical screening program during 13 years. At enrollment, patients described and quantified their LTPA levels and were grouped into five activity levels (from “inactive” to “very high volume”).

Fifty-four percent of patients were “inactive” (<60 minutes of LTPA weekly), and another 22% were “low volume” (average, 92 minutes weekly). After a mean follow-up of 8 years, compared with inactive individuals, those with low-volume activity had significantly lower mortality from all causes (hazard ratio, 0.86), all cancers (HR, 0.90), cardiovascular disease (HR, 0.81), and ischemic heart disease (HR, 0.75), and a significantly lower incidence of all cancers (HR, 0.94). Most of these health benefits increased in dose-related fashion as activity level rose.

Comment: This cohort study cannot establish causation, but an average of 15 minutes of daily exercise — half the recommended amount — was associated with significantly lower 8-year mortality and cancer incidence. Many people might find this modest level of exercise more achievable than the recommended level; its potential benefit could encourage inactive individuals to introduce some level of exercise into their daily routines.

Bruce Soloway, MD

Published in Journal Watch General Medicine September 6, 2011


Wen CP et al. Minimum amount of physical activity for reduced mortality and extended life expectancy: A prospective cohort study. Lancet 2011 Aug 16; [e-pub ahead of print]. (

The Lancet, Early Online Publication, 16 August 2011
doi:10.1016/S0140-6736(11)60749-6Cite or Link Using DOI

Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study

Original Text

Dr Chi Pang Wen MD a b Corresponding Author Email Address, Jackson Pui Man Wai PhD c †, Min Kuang Tsai MS a b, Yi Chen Yang MS a b, Ting Yuan David Cheng MS d, Meng-Chih Lee MD e, Hui Ting Chan MS a, Chwen Keng Tsao BS f, Shan Pou Tsai PhD g, Xifeng Wu MD h



The health benefits of leisure-time physical activity are well known, but whether less exercise than the recommended 150 min a week can have life expectancy benefits is unclear. We assessed the health benefits of a range of volumes of physical activity in a Taiwanese population.


In this prospective cohort study, 416 175 individuals (199 265 men and 216 910 women) participated in a standard medical screening programme in Taiwan between 1996 and 2008, with an average follow-up of 8·05 years (SD 4·21). On the basis of the amount of weekly exercise indicated in a self-administered questionnaire, participants were placed into one of five categories of exercise volumes: inactive, or low, medium, high, or very high activity. We calculated hazard ratios (HR) for mortality risks for every group compared with the inactive group, and calculated life expectancy for every group.


Compared with individuals in the inactive group, those in the low-volume activity group, who exercised for an average of 92 min per week (95% CI 71—112) or 15 min a day (SD 1·8), had a 14% reduced risk of all-cause mortality (0·86, 0·81—0·91), and had a 3 year longer life expectancy. Every additional 15 min of daily exercise beyond the minimum amount of 15 min a day further reduced all-cause mortality by 4% (95% CI 2·5—7·0) and all-cancer mortality by 1% (0·3—4·5). These benefits were applicable to all age groups and both sexes, and to those with cardiovascular disease risks. Individuals who were inactive had a 17% (HR 1·17, 95% CI 1·10—1·24) increased risk of mortality compared with individuals in the low-volume group.


15 min a day or 90 min a week of moderate-intensity exercise might be of benefit, even for individuals at risk of cardiovascular disease.


Taiwan Department of Health Clinical Trial and Research Center of Excellence and National Health Research Institutes.
0 Comments Read more