Bottom line: Maybe. The jury is still out. It may come as a surprise that we don’t have a lot of proof that treating older individuals with cholesterol lowering medications in a class called statins, reduce cardiovascular disease and mortality. The following is a large retrospective study. For review, here is the definition of what a retrospective study is.
A retrospective study looks backwards and examines exposures to suspected risk or protection factors in relation to an outcome that is established at the start of the study. Many valuable case-control studies, such as Lane and Claypon’s 1926 investigation of risk factors for breast cancer, were retrospective investigations. Most sources of error due to confounding and bias are more common in retrospective studies than in prospective studies. For this reason, retrospective investigations are often criticized. If the outcome of interest is uncommon, however, the size of prospective investigation required to estimate relative risk is often too large to be feasible. In retrospective studies the odds ratio provides an estimate of relative risk. You should take special care to avoid sources of bias and confounding in retrospective studies.
The following is a summary of the study from Journal Watch. Following that there is a link to the original article.
July 7, 2020
Statins for Primary CV Prevention in Older Adults
Thomas L. Schwenk, MD reviewing
In a retrospective study, initiating statins in older patients was associated with lower mortality during 7 years of follow-up.
The relatively small number of older adults who have been enrolled in prior randomized, controlled trials (RCTs) of statins has led to uncertainty regarding their value in primary prevention of atherosclerotic cardiovascular disease. Investigators used the Veterans Health Affairs database to perform a retrospective cohort study of about 327,000 patients (age, ≥75; mean age, 81; mostly white men) without prior statin use; about 57,000 received new statin prescriptions during mean follow-up of 7 years. Patients with any form of cardiovascular disease at baseline and those who died within 150 days of enrollment were excluded. Patients with cancer, dementia, or paralysis were not excluded.
Crude cardiovascular-related mortality for statin users and nonusers was 22.6 and 25.7 per 1000 person-years, respectively. Corresponding all-cause mortality was 78.7 and 98.2 per 1000 person-years. In analyses adjusted for a wide range of clinical and demographic variables, statin initiation was associated with significantly lower cardiovascular-related and all-cause mortality (hazard ratios, 0.80 and 0.75, respectively).
Despite its retrospective nature, this study benefited from a large national database, robust adjustment, and inclusion of patients with underlying severe noncardiovascular conditions. Based on these results, some clinicians might decide to initiate statins for primary prevention in patients older than 75. However, at least some residual confounding is likely in this retrospective study, and other clinicians might prefer to wait until ongoing RCTs of statins for primary prevention in older patients are completed.
For now we will still need further evidence of their effectiveness in this age group, but some may elect to treat pending the outcomes of randomized controlled trials.