Urban‐rural differences in the prevalence of Subjective Cognitive Decline in India: A comparative study

Abstract

AbstractBackgroundSubjective Cognitive Decline (SCD), defined as a self‐experienced persistent cognitive decline with a normal performance in objective neuropsychological assessments is one of the first clinical manifestations of dementia. SCD has a strong association with depression, and more research is needed to understand the relationship between the two. When they co‐occur the risk of developing dementia increases. Despite the increased focus on the preclinical stages of dementia such as SCD there is limited research on its prevalence specifically in India. The present study aims to bridge this research gap by estimating the prevalence of SCD in India and assessing urban‐rural differences in its prevalence as well as sociodemographic factors.MethodThe study used data from two ongoing community‐based prospective cohort studies, namely the Tata Longitudinal Study of Ageing (TLSA) and Srinivaspura Aging, Neuro Senescence and COGnition (SANSCOG) in urban Bangalore and Srinivaspura respectively (Sundarakumar et al., 2020). Baseline data collected from 4429 participants aged 45 years and older were included in the analysis. The study used Clinical Dementia Rating Scale (CDR) scores and participants' responses to the questions pertaining to subjective cognitive impairment in Cognitive Function Instrument (CFI) and Geriatric Depression Scale (GDS) to estimate the prevalence of SCD.ResultOf 4429 participants recruited between 2015 and 2022, a total of 1010 (22.8%) participants [median (IQR) age, 60 (15)] were classified as having SCD. As shown in Tabe1, the prevalence was higher in the rural cohort than in the urban cohort (25.1% vs 14.0%, p<0.001). The rural cohort was also found to be comparatively younger (57 (15) vs 63 (14)), and have fewer years of education (4 (9) vs 15(2)). Depression was found to have significant association with SCD in both the cohorts, with more depressive symptoms observed in the rural cohort. As shown in Table 2, the prevalence of SCD was higher in women than men in the urban cohort.ConclusionThe study’s findings indicate that despite being comparatively younger, the rural cohort had a higher prevalence of SCD, potentially due to the protective effect of higher years of education in the urban cohort.