Compliance with sulfonylureas in a health maintenance organization: A pharmacy record-based study

OBJECTIVE: To determine which factors affect compliance with sulfonylureas in a population served by a health maintenance organization in Southern Cal ifornia, METHODS: Retrospective analysis of pharmacy records and healthcare utilizat ion data for two years (April 1993-March 1995), and a sun;ey mailed to pati ents, Patients treated with sulfonylureas were selected for analysis on the basis of their prescription profile, Compliance was measured from the phar macy records as the proportion of days the patient was in possession of the prescribed medications, patient compliance with sulfonylureas was modeled as a function of four clusters of determinants: patient-related attributes, drug regimen characteristics and complexity, health status and disease-rel ated variables, and characteristics of the interaction with healthcare prov iders. RESULTS: 786 patients were identified for analysis (49.1% women, mean age 5 9 y). The mean compliance rate was 83% +/- 22% SD. Compliance was significa ntly positively related with age and self-reported level of medication-taki ng compliance at baseline. Factors shown to have an inverse relationship wi th compliance were treatment complexity, perception of general health, and being a newly treated patient (adjusted R-2 for the final model = 0.148). CONCLUSIONS: Our results suggest that factors found to be associated with n oncompliant behavior (e.g,, being a newly treated patient, self-reported co mpliance, regimen complexity) can be assessed by physicians and pharmacists as a routine practice.