Medication Adherence and Medication Appropriateness among Patients Receiving Insulin Therapy for the Management of Diabetes Mellitus: A Cross-sectional Observational Study

Abstract

Background: Diabetes Mellitus (DM) is a common chronic noncommunicable disease with increasing prevalence leading to serious complications. Effective management of DM depends on the use of appropriate medications and the patients' adherence to the prescribed medication regimen. Objectives: To assess medication adherence, medication appropriateness, and the impact of sociodemographic factors on medication adherence in patients receiving insulin therapy for diabetes management Methods: A cross-sectional observational study was conducted among the patients receiving insulin therapy for the management of DM in the Diabetes and Endocrinology Unit of National Hospital Kandy, Sri Lanka. Eligible patients were selected using a simple randomization method and recruited after obtaining written and verbal consent. A complete medication history was obtained to assess their medication adherence using the Brief Medication Questionnaire (BMQ). Patients were categorized into four adherence groups based on their score for each screen in BMQ. The relationship between sociodemographic factors and medication adherence was evaluated. Appropriateness of the clinic medication list was assessed using the Medication Appropriateness Index (MAI). Results: A total of 385 patients were recruited. The mean±SD BMQ score was 1.24±1.05, and optimal adherence was defined as a BMQ score of zero. Most of the patients were probable poor adherents (n=168, 43.6%), followed by probable adherents (n=103, 26.8%), poor adherents (n=79, 20.5%) and complete adherents (n=35, 9.1%). Medication adherence was significantly influenced by the age (p<0.001), marital status (p<0.001), and education level (p<0.001). The mean±SD MAI score was 0.28±0.23. Conclusions: Medication adherence was sub-optimal among most participants and was impacted by some sociodemographic features. The clinic medication list showed considerable appropriateness. However, it can be further improved to be ideal according to current treatment guidelines. These findings highlight the need to assess medication adherence and medication appropriateness to enhance patient care and therapeutic outcomes.