Abstract
OBJECTIVES:
The primary objective of this study was to determine medication compliance rates and dyslipidemia control in a patient population receiving simvastatin or atorvastatin (statins) in a unique staff-model health maintenance organization (HMO). The secondary objective of this study was to measure the effect of gender and statin regimen on the success rate of dylipidemia control and medication compliance.
METHODS:
This was a retrospective chart review conducted for patients with a diagnosis of dyslipidemia who received monotherapy with a statin for cholesterol reduction. Patients received care at an outpatient clinic during a 12-month study period (December 1998 through December 1999). Patients were excluded if they did not have a low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) concentration obtained in 1999, did not have a statin prescription filled at least twice the during study period, discontinued statin therapy, or received a statin other than simvastatin or atorvastatin. Patient medication compliance was assessed using the medication possession ratio (MPR). Dyslipidemia control rates were determined according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) II guidelines.
RESULTS:
A total of 819 patients met inclusion criteria for study enrollment (55% male, 45% female). The mean age of the patients was 68.5 years. The mean MPR for the entire study group was 0.96±0.23. Men and women had similar mean MPR values (0.97±0.23 vs. 0.96±0.22, respectively; P=0.76). A nearly identical proportion of patients who received either atorvastatin or simvastatin achieved their LDL-C goal, 70.0% vs. 69.6%, respectively. Gender was not related to success rate, with 73.0% of women and 66.9% of men achieving their NCEP directed LDL-C goal (P=0.06). The rate of attainment of ATP II LDL goal was 43.2% (92 of 213) for patients with goal less than 100 mg/dL, 69.1% (226 of 327) for less than 130, and 90.7% (252 of 279) for patients with goal less than 160 mg/dL.
CONCLUSIONS:
Patients enrolled in a unique staff-model HMO who received either simvastatin or atorvastatin exhibited high medication compliance and dyslipidemia control rates. Gender did not affect medication compliance or attainment of LDL-C goal, and the success of achieving dyslipidemia control was not different between atorvastatin and simvastatin.