Adherence to Statins and LDL-Cholesterol Goal Attainment

Objectives: To examine the relationship between low-density lipoprotein cholesterol (LDL-C) goal attainment and adherence to statin medications in patients with coronary artery disease (CAD). Study Design: Cross-sectional study of CAD patients 18 years of age or older in an integrated healthcare system. Methods: Patients dispensed 2 or more statin prescriptions between May 2009 and May 2010, were identified. Medication possession ratio (MPR) was calculated to estimate adherence. The LDL-C value closest to May 27, 2010, was used to determine goal. Adherence and LDL-C goal were defined as 80% or greater MPR and less than 100 mg/dL or less than 70 mg/dL, respectively. Electronic medical records were used to identify patient demographics and clinical information. Logistic regression was used to estimate the effect of these factors on goal attainment. Results: A total of 67,100 CAD patients were identified. Overall, 85.8% had LDL-C less than 100 mg/dL, 32.4% had LDL less than 70 mg/dL, and 79.8% were adherent to their statin medication. Over 65% of patients not at LDL-C goal less than 100 mg/dL were adherent. Among patients with LDL-C less than 100 mg/dL, 17.9% were not adherent. Increasing medication adherence was associated with improved LDL-C levels. Adherence to statins, male sex, Asian and Hispanic race/ethnicity, a higher number of concurrent prescriptions, higher Charlson Comorbidity Index, and hypertension were associated with LDL-C goal attainment. Conclusions: Incorporating LDL-C levels and medication adherence at the point of care allows providers to focus interventions to address either adherence challenges or the need for medication titration in an effort to improve LDL-C goal attainment and ultimately reduce morbidity and mortality.