Predictors of adherence to statins for primary prevention

Purpose Statins are potent drugs for reducing cholesterol and cardiovascular disease; however, their effectiveness is significantly compromised by poor adherence. This prospective study was designed to identify potentially modifiable patient factors including medication, disease, and diet beliefs related to statin adherence. Methods Veterans (n=71) given their first prescription of a statin for primary prevention were interviewed at baseline, 3 months, and 6 months regarding medication, disease, and diet beliefs along with self-reported statin adherence. Results At 6-month follow-up, 55% of the cohort was non-adherent with 10% reporting never having started their statin, 50% reporting misconceptions about the duration of treatment and a median use of < 2 months among those who discontinued their statin. Multivariate predictors of non-adherence were expected short treatment duration ( OR= 3.6, 1.4-9.4), low perceived risk of myocardial infarction ( OR= 3.1, 1.1-8.7), concern about potential harm from statins ( OR= 2.5,1.0- 6.3), being Hispanic ( OR= 3.9, 1.0-15.2), and younger age ( OR= 4.2, 1.1-15.8). Conclusions Poor adherence to statins was common in this primary prevention population with frequent early discontinuation despite access to low-cost medicines. Patient factors regarding the perception of risk, toxic effects of medication, expected treatment duration, as well as socio-demographic factors, were significant predictors of poor adherence and warrant further exploration.