Social engagement, formal education, and cognitive outcomes among older adults in India: A longitudinal population-based study.

INTRODUCTION: We estimated the associations between baseline social engagement and cognitive function and change among older adults in India, overall and by education. METHODS: Data were from 3869 adults aged ≥ 60 years from the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia Wave 1 (2017-2019) and Wave 2 (2022-2024). Baseline social engagement was measured using a 12-point index, dichotomized as higher (< 8) versus lower (≥ 8) engagement. General and domain-specific cognitive scores were derived at both waves. Multivariable-adjusted joint models accounted for mortality and evaluated effect modification by education. RESULTS: Higher baseline social engagement was associated with higher general cognitive scores at baseline (0.145 standard deviation units; 95% confidence interval: 0.076, 0.214), but not with cognitive change over time. Education attainment did not show a consistent pattern of effect modification across cognitive domains. DISCUSSION: Social engagement was associated with cognitive level at baseline but not the rate of cognitive change over time, with no consistent evidence of effect modification by education.