Medication Adherence and its Predictors in Patients With Type 2 Diabetes Mellitus in India: A Systematic Review and Meta‐Analysis of Current Evidence

Background and Aims: India has nearly 90 million (10.5%) patients living with type 2 diabetes mellitus (T2DM) with a high burden of suboptimal medication adherence. This systematic review and meta-analysis aimed to synthesize the determinants of medication adherence in Indian patients with T2DM, estimate the pooled prevalence of adherence, and formulate evidence-based recommendations for public health policy. Methods: We conducted a systematic review and meta-analysis of observational and experimental studies from India, published between January 2020 and December 2024. Electronic databases (PubMed, Scopus, Web of Science) were searched for studies reporting the proportion of patients reporting poor adherence to anti-diabetic medications. Results: = 4) was 48% (95% CI: 18%-79%), and, overall, among all the studies ranged from 11% to 68%. Predictors of poor adherence included older age, socio-economic disadvantage, substance use, treatment complexity, psychological distress, polypharmacy, and health-system access barriers. Information on comorbidity and multimorbidity was sparse. Furthermore, a key limitation was that studies using the Morisky adherence scales (MMAS-4/8) did not report individual item responses, which precluded a granular analysis of specific reasons for non-adherence. There were eight studies from South India and six from north and north-eastern India, indicating a significant lack of geographic diversity. Conclusion: Medication non-adherence in patients with T2DM persists as a major public health challenge in India, further exacerbating the country's burgeoning diabetes epidemic. Strengthening primary care can address the primary factors contributing to significant non-adherence in this population.