Age and sex dynamics in the incidence of diabetes in Contributory Health Services Scheme beneficiaries: A retrospective cohort study in Mumbai

Abstract

ABSTRACT Introduction: A comprehensive body of literature addresses self-reported diabetes prevalence, yet a notable gap exists in research investigating the clinically ascertained incidence of diabetes in India through rigorous longitudinal data analysis. This study aimed to determine the incidence of clinically diagnosed diabetes in a nondiabetic cohort. Materials and Methods: The research gathered data from 1669 participants (aged 30 years and above) enrolled in a government hospital’s Contributory Health Services Scheme, utilizing electronic medical records. Clinical diagnosis of diabetes relied on three laboratory tests. A cohort of initially diabetes-free individuals in 2011–2012 was tracked for 10 years to assess diabetes incidence. Age-adjusted incidence rates were determined through survival analysis techniques. Results: Over a decade-long observational period, 552 beneficiaries within the study cohort were clinically diagnosed with diabetes, yielding an age-adjusted incidence rate of 38.9 cases per 1000 person-years (PYs) spanning from 2013 to 2021. Stratifying by gender, age-adjusted incidence rates were notably elevated in males compared to females, with rates of 41.5 versus 38.5 cases per 1000 PYs, respectively. Further analysis revealed the highest incidence rates among males aged 55–59 years (60.5 per 1000 PYs) and females aged 65–69 years (83.4 per 1000 PYs). Conclusion: This extended follow-up investigation transpired in a setting characterized by uniform health-care provision, devoid of discernible access differentials, or inequalities, thereby enhancing the credibility of the ascertained diabetes incidence rates.