Prevalence of DSM-5 mild and major neurocognitive disorder in India: Results from the LASI-DAD

Abstract

AbstractIntroductionIndia, with its rapidly aging population, faces an alarming burden of dementia. We implemented DSM-5 criteria in large-scale, nationally representative survey data in India to characterize the prevalence of mild and major Neurocognitive disorder.MethodsThe Longitudinal Aging Study in India’s Diagnostic Assessment of Dementia (LASI-DAD) (N=4,096) is a nationally representative cohort study in India including 36 Indian states and union territories using multistage area probability sampling methods. Using neuropsychological testing and informant reports, we defined DSM-5 mild and major neurocognitive disorder, reported its prevalence, and evaluated criterion and construct validity of the algorithm using clinician-adjudicated Clinical Dementia Ratings (CDR).ResultsThe prevalence of mild and major neurocognitive disorder, weighted to the population, is 17.6% and 7.2%. Demographic gradients with respect to age and education conform to hypothesized patterns. Among N=2390 participants with a clinician-adjudicated CDR, CDR ratings and DSM-5 classification agreed for N=2,139 (89.5%) participants.DiscussionThe prevalence of dementia in India is higher than previously recognized. These findings, coupled with a growing number of older adults in the coming decades in India, have important implications for society, public health, and families. We are aware of no previous Indian population-representative estimates of mild cognitive impairment, a group which will be increasingly important in coming years to identify for potential therapeutic treatment.