reports

Adherence with lipid-lowering, antihypertensive, and diabetes medications

Am J Pharm Benefits 3:165-171.

Hawaii Medical Service Association, Honolulu, HI, USA

OBJECTIVES: To investigate the combinations of medications patients were taking, the study examined trends in adherence over time, relative medication adherence, and the consistency of individual patient adherence from year to year.

STUDY DESIGN: Retrospective review of administrative claims data.

METHODS: The study population consisted of patients enrolled with the largest insurer in Hawaii, which covers approximately 650,000 lives. Study participants (n = 148,119) had hypertension, dyslipidemia, and/or diabetes and filled a prescription for a medication for 1 or more of these 3 conditions between 2004 and 2008. The primary outcome was medication possession ratios, defined as the proportion of days enrolled in a year that were covered by a filled prescription. Patients with a medical possession ratio of 80% or higher were considered adherent. Analyses included regression models adjusted for multiple variables.

RESULTS: Patients had lower average adherence with lipid-lowing medications than with antihypertensive medications, and had the highest average adherence with medications for diabetes. Medication adherence was highest among patients taking the largest number of drugs for hypertension, hyperlipidemia, and diabetes. Rates across years also showed that patients with more complex regimens were most likely to sustain good adherence.

CONCLUSION: Patients taking medicines for more of the study conditions were more likely to be adherent than patients taking medications for fewer of the conditions. New strategies are needed to encourage healthier patients to adhere with their medications.