Poor adherence to oral antidiabetic drugs among people living with type 2 diabetes mellitus in two healthcare facilities in the West Region (Cameroon): a cross-sectional study

Background: Type 2 diabetes mellitus (T2DM) is a significant public health issue worldwide. Few individuals with T 2 DM achieve adequate glycaemic control, possibly due to poor adherence, which may be linked to adverse events. This study aimed to assess the distribution of poor adherence and examine the relationship between adverse events and poor adherence to oral antidiabetic medications in individuals with T 2 DM. Methods: We conducted a cross-sectional study at two regional hospitals in the West Region of Cameroon. Adherence was assessed using the 8-item Morisky scale questionnaire. Data were analyzed with SPSS 23. 0. The Fisher chi-square test was utilised to explore associations between categorical variables. Results were deemed statistically significant when the p-value was less than 0. 0.05. Results: A total of 248 participants (105 males) were recruited, with a median age of 62 years (IQR 52-69). The median duration of diabetes was 6 years (IQR 3.00-11.75). Only 66 participants (26.6%) had achieved glycated hemoglobin levels in the previous three months, with poor glycemic control observed in 48 (72. 2%) of these individuals. Adverse events were reported by 40 participants (16.1%), mostly related to metformin use. The most common adverse event was heartburn (19 cases, 47. 5%). The prevalence of poor adherence was 46. 4% (95% CI: 40. 3-52. 8) and was associated with the use of herbal medicine (aOr = 3. 10 [95% CI: 1. 71 – 5. 61]; p = 0. 001), lower education levels (aOr = 2. 85 [95% CI: 1. 19 – 6. 83]; p = 0. 02), overweight/obesity (aOR = 2. 41 [95% CI: 1. 21- 4. 80]; p = 0. 012), concurrent intake of antidiabetic medications with other drugs (aOr = 0. 47 [95% CI: 0. 24 – 0. 93]; p = 0. 03), and the presence of at least one complication (aOr = 0. 56 [95% CI: 0. 33-0. 95]; p = 0. 04). Conclusion: Among individuals with T2DM followed in two regional hospitals in the West Region, nearly half exhibited poor adherence. One in six reported adverse events. The use of herbal medicine, limited education, and overweight/obesity increased the risk of poor adherence. Enhanced therapeutic education is essential to improve this situation.