The role of health literacy in medication adherence: Evidence from a greater western Sydney study of Indian migrants living with type 2 diabetes mellitus.

Abstract

Type 2 Diabetes Mellitus (T2DM) presents a major public health challenge globally, disproportionately affecting Indian migrants who are vulnerable to diabetes-related complications due to cultural, linguistic and systemic barriers that can limit access to timely and effective care. Health literacy is a key determinant of T2DM management, yet its association with medication adherence in this population remains underexplored. This study investigates the association between performance-based (objectively assessed) and self-reported (subjectively assessed) health literacy and medication adherence among Indian migrants with T2DM, while accounting for a range of demographic, socioeconomic and health-specific factors. A cross-sectional study design was employed. Participants (n = 309) were recruited through multicultural health services, and hospital diabetes clinics across Greater Western Sydney, a socioeconomically and culturally diverse area of Sydney, NSW, Australia. Eligible participants self-identified as Indian, were aged 18 years or older, had been diagnosed with T2DM for at least one year, and were currently prescribed diabetes medication. Data were collected via a structured survey and analysed using multivariate logistic regression. Low health literacy was prevalent among Indian migrants, with over 67.6% demonstrating low performance-based health literacy and 62.5% reporting low self-reported health literacy. Approximately 68.9% of participants had low medication adherence. Lower medication adherence was significantly and positively associated with lower health literacy, both performance-based (adjOR=9.14, 95%CI: 4.24-19.72; p = <0.001) and self-reported (adjOR=12.45, 95%CI: 4.55-34.10; p = <0.001). Key predictors of medication adherence included health literacy, private health insurance, BMI, glucose level, comorbidities and social support. Models differed slightly depending on the type of health literacy assessed. Health literacy plays an important role in diabetes self-management for Indian migrants. These findings highlight the need for culturally tailored interventions that address both health literacy support - such as improving understanding of medical information and navigating healthcare systems - and social or family support systems that influence health behaviours and decision-making.