Mobility-Related Disability, Body Mass Index, and Cardiometabolic Disease Among Adults in Puducherry, India: A Cross-Sectional Mediation Analysis

BackgroundMobility-related disability and cardiometabolic disease frequently coexist, but the contribution of adiposity to this association remains uncertain.We examined the association between mobility-related disability and hypertension and/or diabetes, with body mass index (BMI) as a potential mediator, among adults in Puducherry, India. Materials and methodsThis community-based cross-sectional study included 1,376 adults recruited from 18 wards/villages using multistage cluster sampling.Mobility-related disability was defined as any self-reported difficulty in the mobility domain of the World Health Organization rapid Assistive Technology Assessment tool.BMI was modeled continuously, and the primary outcome was hypertension and/or diabetes.Adjusted linear and logistic regression models included prespecified demographic, socioeconomic, behavioral, and familyhistory covariates.Indirect effects were estimated within a counterfactual framework using ward-level clustering and 5,000 quasi-Bayesian simulations.Small-cluster sensitivity analyses included CR2-adjusted regression inference and a 999-replicate ward-level bootstrap. ResultsMobility-related disability was reported by 144 participants (10.5%), and 586 (42.6%) had the composite cardiometabolic outcome.Mobility-related disability was associated with a higher BMI (adjusted β = 2.36 kg/m²; 95% CI: 1.04-3.68).Each 1 kg/m² increase in BMI was associated with 1.08 times the adjusted odds of cardiometabolic disease (95% CI: 1.05-1.11).The average causal mediation effect (ACME) through BMI corresponded to a significant 3.8-percentage-point difference in the predicted probability of cardiometabolic disease (ACME = 0.038; 95% CI: 0.015-0.067).The indirect estimate remained positive in all 18 leave-one-cluster-out analyses and in the ward-level bootstrap (95% CI: 0.020-0.058). ConclusionsBMI showed a positive statistical indirect association between mobility-related disability and cardiometabolic disease, supporting consideration of adiposity as a potentially modifiable factor in disability-inclusive cardiometabolic risk assessment.Further evaluation is needed for accessible nutrition, weight management, physical activity, and screening approaches.However, the cross-sectional nature of the study prevents the establishment of a causal pathway.