Abstract
Background/Aims While it is known that cholesterol control in coronary artery disease (CAD) patients is essential for preventing recurrent coronary events, studies continue to show that adherence to lipid-lowering drugs is suboptimal. The clinical decision on how best to manage a patient with suboptimal adherence and at goal for LDL-c is different than for a patient with optimal adherence and not at goal.
Methods We examined the rate of LDL-c goal attainment, defined as <100 mg/dL, by level of adherence to statins in CAD patients aged >18 years in a diverse integrated health care delivery system serving over 3.2 million members. Patients in the May 2010 CAD Registry and dispensed >2 statin prescriptions on two unique dates between June 2009 and May 2010 were identified through electronic medical records. Patients with rhabdomyolysis, creatinine kinase >10,000 IU/L, allergy or intolerance to statins and those without LDL-c results, continuous membership or drug benefits in the previous 12 months were excluded. Medication adherence was calculated as the ratio of the number of days supply to the number of days between the first and last fill over 400 days. Adherent behavior was defined as >80%.
Results Altogether, 67,100 CAD patients (63% male) with a mean (SD) age of 71.4 (10.7) years were identified. Over 85.8% were at LDL-c goal attainment and 79.8% had >80% adherence with 53.1% having 96–100% adherence. LDL-c goal attainment had a positive association with increasing adherence, but goal attainment leveled off once adherence was over 86%. Over 65% of patients not at goal were adherent while 23.9% of patients not at goal were not adherent (26.9% in women and 21.8% in men). Patients aged >65 years had the highest rates of adherence (81.6%) and men had consistently higher rates of adherence compared with women in all age groups.
Conclusions Although overall LDL-c goal attainment was high in this population, there is still a substantial proportion of patients not adherent and not at goal. Targeted interventions based on LDL-c goal attainment should be undertaken to ensure that adherence to statin therapy is maintained in this high-risk population of CAD patients.
