Comparison of obesity, diabetes, hypertension and depression in two parallel, aging study cohorts from rural and urban India: SANSCOG study and TLSA

Abstract

AbstractBackgroundPopulation aging has contributed to high global prevalence of dementia, particularly in developing countries like India. Increasing evidence indicates that the pathogenesis of dementia starts several decades before its symptoms become manifest, thus making it important to identify the risk and protective factors even before the onset of its clinical features. Longitudinal, population‐based, aging studies offer an excellent opportunity to do this.MethodSrinivaspura Aging, Neuro Senescence and COGnition (SANSCOG) study and Tata Longitudinal Study on Aging (TLSA) are parallel, prospective, community‐based, cohort studies in India – rural and urban, respectively – for comprehensive evaluation of risk and protective factors associated with cognitive changes due to normal ageing, dementia and other related disorders. Both the study cohorts comprise of cognitively healthy individuals aged ≥ 45 years. However, they have distinct population characteristics with respect to socio‐economic status, migration, literacy and lifestyle. Participants in the SANSCOG study are recruited from the villages of Srinivaspur Taluk in Kolar District in southern India, through an area sampling strategy, whereas, those in TLSA are recruited through convenience sampling, from urban Bangalore, India. Participants undergo detailed clinical and neuro‐psychiatric assessments that provide valuable data on a variety of health parameters, including vascular risk factors. Harmonization in clinical evaluations across the two studies enable head‐to‐head comparison of clinical outcome measures. Preliminary analysis was done on parameters such as obesity, hypertension, diabetes and depression that are assessed in the above two cohorts.ResultThere was a statistically significant difference in BMI between the two cohorts – the urban cohort had substantially higher proportion of those with obesity than the rural cohort. Diabetes was over two‐fold more common in the urban cohort than the rural cohort. The proportion of persons with Hypertension was also much higher in the urban than in the rural cohort. Depression (Geriatric Depression Scale score ≥ 10) was slightly higher in the rural cohort than the urban cohort.ConclusionVascular risk factors were strikingly higher in the urban cohort than the rural cohort. Long‐term follow‐up of these risk factors along with parallel monitoring of cognitive changes will help in predicting risk factors for dementia in this population.