Modifiable risk factors for dementia in India: a cross-sectional study revisiting estimates and reassessing prevention potential and priorities

Abstract

Background About 16% of worldwide dementia cases are in India. Evaluating the prospects for dementia prevention in India requires knowledge of context-specific risk factors, as relationships between risk factors and dementia observed in high-income countries (HICs) may not apply.Methods We computed population attributable fractions (PAFs) for dementia in India by estimating associations between risk factors and dementia, their prevalence and communality, within the same nationally representative sample of 4096 Indians aged 60 and older, surveyed through the Harmonised Diagnostic Assessment of Dementia for the Longitudinal Ageing Study in India.Results The risk factor with the largest PAF (>20%) was no education, followed by vision impairment (14%), physical inactivity (12%) and social isolation (8%). According to our estimates, eliminating exposure to risk factors significantly associated with dementia would potentially prevent up to 70% of dementia cases in India.Discussion Previous estimates, based on samples limited to specific geographic areas and using risk factors’ definitions and relative risks from HICs, may not correctly estimate the real opportunities for preventing dementia in India or identify the most critical areas for intervention.