Any benefit of statins for primary prevention in older adult populations may depend on whether or not type 2 diabetes is present, results of a retrospective cohort study suggest.
Statins had no protective effect overall in the study, which included adults older than 74 years who had no clinically recognized atherosclerotic cardiovascular disease (ASCVD).
In older patients with diabetes, statins were associated with reductions in CVD incidence and all-cause mortality. However, this benefit was substantially reduced in patients 85 years and older, and completely absent in those over 90, study authors said in.
“These results do not support the widespread use of statins in old and very old populations, but they do support treatment in those with type 2 diabetes younger than 85 years,” said Rafael Ramos, MD, of the University of Girona, Spain, and his coauthors.
While meta-analyses support statins as primary prevention of CVD in individuals 65 years or older, evidence is lacking on those older than 74 years, according to the investigators.
Accordingly, they conducted the present retrospective cohort study based on data from a Spanish primary care database that included patient records for more than 6 million people. They looked specifically for individuals aged 75 years or older with no history of ASCVD who had at least one visit between July 2006 and December 2007.
They found 46,864 people meeting those criteria, of whom 7,502 (16.0%) had started statin treatment and 7,880 (16.8%) had type 2 diabetes.
With a median follow-up of 7.7 years, statin use had no benefit in reducing ASCVD incidence or all-cause mortality for the entire study population, statistical analyses showed.
In participants with diabetes, however, statins did appear protective, at least in the patients aged 75-84 years, with hazard ratios of 0.76 (95% confidence interval, 0.65-0.89) for CVD and 0.84 (95% CI, 0.75-0.94) for all-cause mortality, Dr. Ramos and his colleagues reported.
The 1-year number needed to treat in this 75-84 age group was 164 for atherosclerotic CVD, and 306 for all-cause mortality, they added.
By contrast, the hazard ratios for patients 85 years and older were 0.82 (95% CI, 0.53-1.26) for atherosclerotic CVD, and 1.05 (95% CI, 0.86-1.28) for all-cause mortality, the investigators reported.
The observed reductions in CVD in individuals with diabetes lost statistical significance at age 85 years when investigators looked at hazard ratios for each year of age. Similarly, reductions in all-cause mortality began to lose statistical significance at age 82 years and “definitively disappeared” in those aged 88 years or older, they said.
The project was supported by grants from the Ministerio de Salud, Spain’s Ministry of Science and Innovation through the Carlos III Health Institute and other entities.
Dr. Ramos and his coauthors declared no support in the previous 3 years from any organization related to, or that might have an interest in, the submitted work. They also declared no other relationships or activities that could appear to have influenced the work.
SOURCE: Ramos R et al. .