Medication adherence and influencing factors in patients with type 2 diabetes attending a tertiary hospital in South-West Nigeria

Background and Objectives: Adherence to antidiabetic medications represents a huge hurdle that needs to be overcome for patients to gain maximum clinical benefits from their therapies. Several factors have been associated with patient adherence. This study assessed adherence to antidiabetic medications and evaluated the influence of pill burden on adherence. Materials and Methods: This is a cross-sectional study of 418 consenting patients with established type 2 diabetes attending the endocrinology Outpatient Clinic of a Tertiary Hospital. Patients were approached consecutively and surveyed using a questionnaire comprising information on demographics, medication adherence, and factors affecting adherence. Data on medication regimen and comorbidities were extracted from participants' case records. The study lasted for 15 months. Data were analyzed and summarized using descriptive and inferential statistics. Results: Nearly 27.5% of the participants were adjudged nonadherent to antidiabetic medications. The average number of antidiabetics was 1.56 ± 0.617. Of the number of participants that are adherent, nearly 33% and 35% of them were on one and two antidiabetic medications, respectively. However, been on three or more medications is associated with poorer adherence. Participants on metformin had better adherence compared to those on insulin alone or insulin plus oral antidiabetics. Short duration of diabetes (P = 0.048), older age (P = 0.024), and high educational level (P = 0.002) are associated with better adherence. Conclusion: A substantial number of patients were non-adherent to their antidiabetic medications. Been prescribed 3 or more antidiabetic medications was associated with poor adherence. The association between adherence to medication and glycemic control is not significant. High Pill-burden, young age, low educational level are potential targets for interventions.