Effect of value–added utilities on prescription refill compliance and Medicaid health care expenditures–a study of patients with non–insulin–dependent diabetes mellitus

Abstract

An estimated 20 million Americans suffer from diabetes. Patients with non–insulin–dependent diabetes mellitus (NIDDM) comprise approximately 90% of the diabetic population. An estimated 10–30% of patients with NIDDM withdraw from their prescribed regimen within 1 year of diagnosis, and of the remainder, nearly 20% administer insufficient medication to facilitate an adequate reduction in blood glucose. A randomized trial was undertaken to discern the effect of pharmacy–based value–added utilities on prescription–refill compliance with sulfonylurea therapy and health service utilization. The subjects were 258 Medicaid beneficiaries from the state of South Carolina, previously untreated for NIDDM, prescribed 5 mg of the second–generation sulfonylurea glyburide twice daily, and monitored with regard to prescription–refill compliance and health service utilization for 1 year. Subjects provided informed consent and were randomly assigned to one of four experimental groups: (i) the control cohort received standard pharmaceutical care with each dispensing of glyburide; (ii) the second cohort received standard pharmaceutical care and was mailed a medication–refill reminder 10 days prior to each sequential refill date; (iii) the third cohort received standard pharmaceutical care and was provided unit–of–use packaging with each prescription–refill request; (iv) the fourth cohort received standard pharmaceutical care, mailed medication–refill reminders, and unit–of–use packaging. Analysis of variance (ANOVA) procedures revealed that patients receiving mailed prescription–refill reminders, unit–of–use packaging, or a combination of both interventions achieved a significant (P ≤005) increase in the Medication Possession Ratio (MPR) for sulfonylurea therapy relative to controls. Receipt of both interventions resulted in a significant (P ≤ 005) improvement in the MPR for sulfonylurea therapy relative to all other groups; no significant difference was discerned between groups receiving either mailed prescription–refill reminders, or unit–of–use packaging. Multivariate regression analysis revealed that patients receiving both interventions experienced a significant (P ≤ 005) reduction in the use of physician, laboratory, and hospital services relative to patients provided standard pharmaceutical care. These results argue for an increased use of pharmacy–based value–added utilities under both public and private health insurance programmes.