Re: Statins for primary prevention of cardiovascular events and mortality in old and very old adults with and without type 2 diabetes: retrospective cohort study
We are not surprised over the lack of statin benefit among most of the participants in the study by Ramos et al. because in a previous meta-analysis of 19 cohort studies of elderly people (≥60 years) including more than 68,000 individuals we found that those with the highest LDL-cholesterol lived the longest; none of the studies found the opposite. In the largest study the authors had also compared longevity among the statin-treated and the non-treated and found that the non-treated lived the longest.
It is not possible to know whether the benefit among the oldest diabetics in the study by Ramos et al. was due to statin treatment without knowing how many of the patients had withheld the treatment, because several studies have shown that more than half of statin-treated patients stop the treatment.[3-5]
We think that our study  explains the benefit among the diabetics age 75-84 years in the study by Ramos et al. because the number with hypercholesterolemia was much higher among those on statin treatment than among the non-treated (53.4% vs 21.8%). That the benefit was due to statin treatment is unlikely because many studies have shown lack of an association between total or LDL-C and cardiovascular disease in diabetic patients.[6-18] In accordance, a systematic review of clinical trials have shown that cholesterol-lowering have been unable to reduce CVD mortality, all-cause mortality and cardiovascular events in type 2 diabetics.
The findings by Ramos et al. are also in accordance with two recent reviews showing that LDL-C is not the cause of atherosclerosis and CVD, not even among individuals with familiar hypercholesterolemia.
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Competing interests: No competing interests