Introduction: Data suggest that the beneficial cardiovascular effects of statins are maximized after the first year of statin use; yet, the timeline of statin-associated adverse events is not well delineated.
Objective: To examine the associations of short-term statin use (≤1 year) with short- and long-term adverse events and beneficial cardiovascular outcomes in a 'healthy' cohort.
Participants and methods: A cohort study of a healthy Tricare population (fiscal year [FY] 2002 through FY 2011) who have no cardiovascular disease, major comorbidities requiring medications, or functional limitations. Statin users used statins for 90-365 days during FY 2005 as their only prescription medication. Nonusers had medical encounters but did not receive prescription medications during FY 2005, and did not receive any statins throughout the study period from FY 2002 to FY 2011. Outcomes were the occurrence of major acute cardiovascular events, diabetes mellitus and its complications, kidney diseases, musculoskeletal diseases, obesity, cataracts, malignancy, and death.
Results: We matched 1525 statin users to 1525 nonusers. During the follow-up period (FY 2006 to FY 2011), statin users had significantly higher odds of developing diabetes and diabetic complications that persisted throughout follow-up (odds ratio [OR] 1.93, 95 % confidence interval [CI] 1.55-2.41 and OR 2.15, 95 % CI 1.20-3.86, respectively). Short-term statin use was not associated with decreased odds of major acute cardiovascular events (OR 1.17, 95 % CI 0.72-1.92). There were no differences in risks of kidney diseases, musculoskeletal diseases, or malignancy.
Conclusions: Short-term statin use for primary prevention in this healthy cohort was associated with an increased risk of long-term diabetes and diabetic complications without cardiovascular benefits. Further study using pragmatic studies and prospective observational studies appropriately equipped to eliminate unidentified confounders are urgently needed.