FACTORS AFFECTING PATIENT COMPLIANCE WITH ANTIHYPERLIPIDEMIC MEDICATIONS IN AN HMO POPULATION

Objective: To identify factors that influence compliance in patients t aking antihyperlipidemic medications. Study Design: This was a retrosp ective cohort study in which computerized pharmacy records were used t o estimate medication compliance in patients in a Health Maintenance O rganization from 1993 to 1995. Patients and Methods: Data on 772 patie nts on antihyperlipidemic medications were obtained from pharmacy and healthcare utilization claims and from a cross-sectional survey. The m edication compliance ratio for each patient was calculated from the pr escription profile. Patient compliance was modeled as a function of fo ur clusters of determinants: patient characteristics, complexity of dr ug regimen, health status, and patient-provider interaction. Correlati on between specific characteristics and compliance was estimated by lo gistic regressions. Results: Approximately 37% of patients complied wi th at least 90% or more of their antihyperlipidemic medications. The f ollowing variables had a significant influence on compliance: female g ender (odds ratio [OR], 0.64), baseline compliance (high: OR, 3.42; me dium: OR, 1.86), perceived health status (SF-36 bodily pain score: OR, 1.02; SF-36 vitality score: OR, 0.97), comorbidity (OR, 0.90), and nu mber of daily doses of antihyperlipidemic medications (OR, 0.60). Conc lusions: The findings suggest that women, patients with comorbidities, patients reporting high SF-36 vitality scores, and patients with mult iple doses of antihyperlipidemic medications are less likely to be com pliant. Patients who self-report good compliance with previous medicat ions are more likely to comply. This information may be used to target interventions at patients who are likely to be noncompliant with thei r medication regimens.