Treating elderly patients who have coronary heart disease (CHD) with a statin reduces all-cause mortality as well as fatal and non-fatal cardiovascular events, a meta-analysis of clinical trial data has found.
The study authors comment that statins may be underused in the elderly because the evidence does not consistently show an overall benefit.
The review and analysis, just published in the Journal of the American College of Cardiology, aimed to determine whether the clinical trial data showed a consistent effect on all-cause mortality in this age group.
The researchers carried out a comprehensive literature search for randomised controlled trials involving statin treatment in patients with CHD at time of randomisation, including at least 50 patients aged 65 and over, and having at least six months’ follow-up and all-cause mortality, CHD mortality, nonfatal MI, need for revascularisation, or stroke reported as an outcome measure.
Unpublished data on elderly subgroups was obtained where possible, and hierarchical Bayesian modelling was used to account for the significant differences between studies.
The initial literature search located 729 papers, of which 66 were potentially relevant and evaluated further.
Of these, nine met the predetermined selection criteria and reported all outcomes studied; for a number of these, previously unpublished subgroup data were obtained from the original study authors.
The total number of elderly patients included in the nine studies was 19,569, ranging from 94 to 10,697 (in HPS), with a mean weighted follow-up of 4.9 years.
About a third of the patients in HPS were enrolled on the basis of noncoronary vascular disease, and the analysis was thus carried out with and without the inclusion of this study. This did not materially affect the results.
Analysis revealed that statin treatment was associated with a relative risk reduction in all-cause mortality of 22% (pooled rates 15.6% vs 18.7%). The calculated number-needed-to-treat (NNT) over five years to save one life was 28 (95% credible interval 15–56).
There were similar relative risk reductions for the other outcomes studied (CHD mortality, 30%, NNT 34; nonfatal MI 26%, NNT 38; stroke 25%, NNT 58).
The authors conclude that statin treatment in elderly patients with CHD reduces all-cause mortality, and that the effect is greater than previously expected.
Subgroup analysis by age indicated that the benefit was greater with increasing age, with the relative risk reduction for those aged 80–97 being 50%.
Women accounted for about a quarter of the study population, and there appeared to be no gender-specific differences in benefits.