For patients with atherosclerotic cardiovascular disease (ASCVD), low adherence to statins is associated with an increased risk for death, according to results published in JAMA Cardiology.
The study included participants who had ≥1 International Classification of Disease, Ninth Revision, Clinical Modification codes for ASCVD on ≥2 dates in the previous 2 years without intensity changes to their statin prescription (N=347,104). Participants were treated within the Veterans Affairs Health System between January 1, 2013 and April 1, 2014.
The researchers defined statin adherence by medication possession ratio (MPR), with adherence defined as an MPR ≥80% for dichotomous analysis. They categorized MPR into <50%, 50%-69%, 70%-89%, and ≥90%. The primary outcome was death from all causes and adherence to other cardiac medications.
Of the participants, 1.6% (n=5472) were women, 10.4% (36.208) were black, 4.7% (n=16,323) were Hispanic, 1.2% (n=4093) were Pacific Islander, 0.4% (n=1293) were Native American, 0.3% (n=1145) were Asian, and 0.5% (n=1794) were other races.
Compared with participants taking high-intensity statin therapy, participants taking moderate-intensity statin therapy were more adherent (odds ratio [OR] 1.18; 95% CI, 1.16-1.20). The researchers also found that women were less likely to be adherent compared with men (OR 0.89; 95% CI, 0.84-0.94), and minority participants were less likely to be adherent compared with white participants.
During a mean follow-up of 2.9 years, 24.8% (n=85,930) participants died. After adjusting for clinical characteristics and adherence to other cardiac medications, participants with an MPR <50% had a hazard ratio (HR) of 1.30 for mortality compared with participants with MPR ≥90%. Participants with an MPR 50%-69% had an HR of 1.21 whereas participants with MPR 70%-89% had an HR of 1.08 compared with the highest adherence group.
“These findings suggest secondary prevention of ASCVD through optimization if there is a substantial opportunity for improvement in the statin adherence,” the researchers wrote.
Rodriguez F, Maron DJ, Knowles JW, et al. Association of statin adherence with mortality in patients with atherosclerotic cardiovascular disease. [published online February 13, 2019]. JAMA Cardiol. doi:10.1001/jamacardio.2018.4936