Clinical obesity phenotypes among older adults: prevalence, determinants, and morbidity burden from the Longitudinal Ageing Study in India.

BACKGROUND

Routine obesity diagnosis in India largely relies on BMI, often failing to capture metabolic heterogeneity in older adults. This study is the first to operationalize the 2025 Lancet consensus framework at a national scale, distinguishing between excess adiposity (pre-clinical) and adiposity with comorbidities (clinical obesity).

METHODS

We analyzed data from 60640 adults aged ≥45 years from the Longitudinal Ageing Study in India (LASI, Wave 1). Using Asian-specific BMI and waist circumference thresholds integrated with physician-diagnosed conditions, participants were classified as without obesity, preclinical obesity, or clinical obesity. Multivariable regression models examined sociodemographic, behavioral, and psychosocial determinants.

RESULTS

Overall, 37.53% of older adults had either preclinical or clinical obesity, comprising 15.00% with preclinical obesity (95% CI: 14.27-15.75) and 22.53% with clinical obesity (95% CI: 21.71-23.37). Non-obesity accounted for 62.47% (95% CI: 61.55-63.39). In the fully adjusted model, higher odds of increasing obesity category were observed among women (AOR = 1.97), urban residents (AOR = 1.88), individuals in the richest MPCE quintile (AOR = 1.91), and socially isolated individuals (AOR = 1.44). Adults aged ≥70 years had lower odds (AOR = 0.80). Compared with individuals without obesity, those with preclinical or clinical obesity had higher prevalence of hypertension, diabetes, chronic heart disease, chronic bone or joint disease, high cholesterol, and multimorbidity.

CONCLUSION

A substantial proportion of older adults in India had preclinical or clinical obesity, particularly women, urban residents, socioeconomically advantaged groups, and socially isolated individuals. Phenotype-based classification adds value beyond BMI by distinguishing excess adiposity without morbidity from adiposity with clinical manifestations, supporting refined population-level risk stratification. Public health strategies should strengthen early identification, integrate waist circumference and morbidity assessment into older-adult NCD screening, and address social and structural factors associated with obesity burden.