Medication adherence among adults with type 2 diabetes in Sri Lanka: A mixed-methods study

Introduction Person-centered care is central to managing long-term conditions; however, medication adherence remains low in many low- and middle-income settings. Objective To determine the level of medication adherence and develop an understanding of medication adherence management among adults living with type 2 diabetes mellitus (DM) in Sri Lanka (SL). Methods A convergent parallel mixed-methods design was used. We conducted a descriptive cross-sectional study in outpatient clinics in the Gampaha District, SL using multi-stage stratified cluster sampling. We recruited adults (≥ 18 years) with type 2 DM on oral medication who had attended clinic follow-up for more than one year and excluded people using insulin. We measured adherence using the Model Medication Adherence (MMA) questionnaire (15 items). We performed multivariable logistic regression to identify factors associated with high adherence (MMA score > 70). In parallel, we used focus groups to explore how patients managed medicines in their daily lives and then integrated quantitative and qualitative findings to develop an explanatory model. Results Of the 954 invited, 950 participated (response rate 99.6%). High adherence was observed in 35.9% (n = 341) of the participants. Higher adherence was associated with normal BMI (aOR 1.63), high numeracy skills (aOR 1.59), DM duration > 5 years (aOR 1.40), never visiting an alternative treatment provider (aOR 2.83), obtaining medicines from a private pharmacy (aOR 2.04), and satisfaction with the time spent with the doctor (aOR 1.85). Lower adherence was associated with perceived medication side effects (aOR 0.47), feeling unfit (aOR 0.51), blurred vision (aOR 0.73), and having a sibling with DM (aOR 0.65). The focus groups highlighted three linked themes that shaped medicine-taking: medication safety concerns, use of multiple healthcare providers, and stigma. Integration suggested four broad approaches to medication adherence management: medicalized, gradual adaptation, contextualized or peer-guided, and traditional remedies. Conclusions Medication adherence was low in this study. Patients managed medicines through symptom experiences, beliefs about safety, plural treatment-seeking, and stigma. Diabetes services should support person-centered consultations that actively elicit concerns, symptoms, and use of traditional remedies, and strengthen communication and practical support for day-to-day medication routines.