Lifestyle associations with hypertension and diabetes risk via metabolic function and physical indicators: a cross-sectional serial mediation model among community adults

Objective To examine whether lifestyle is associated with hypertension and diabetes risk via sequential indirect pathways involving metabolic function and physical indicators among community adults. Methods A cross-sectional study was conducted among 6,178 community adults in Nanning, southern China. Structural equation modeling (SEM) was used to examine the direct and indirect associations among lifestyle, metabolic function, physical indicators, and disease risk. Bias-corrected bootstrap analyses with 5,000 resamples were performed to evaluate indirect associations. Results The model showed acceptable fit (CFI = 0.917, RMSEA = 0.048); the chi-square/df ratio (5.19) was elevated, as is common in samples of this size. Physical indicators exhibited the strongest direct association with disease risk ( β = 0.763, P < 0.001), while metabolic function was also positively associated with disease risk ( β = 0.048, P = 0.010). Healthy lifestyle was associated with lower disease risk via indirect pathways involving physical indicators alone ( β = −0.360, P = 0.001) and via the sequential indirect pathway involving metabolic function and physical indicators ( β = −0.011, P = 0.021). For unhealthy lifestyle, indirect associations with higher disease risk were observed via metabolic function ( β = 0.003, P = 0.036) and physical indicators ( β = 0.092, P = 0.014), whereas the sequential indirect pathway was not statistically significant ( P = 0.104). Direct associations of lifestyle with disease risk were small in magnitude (| β | ≤ 0.035) and of limited clinical importance; only the direct association of unhealthy lifestyle reached statistical significance ( β = −0.035, P = 0.013). Conclusion In this cross-sectional sample, lifestyle was associated with hypertension and diabetes risk primarily via indirect pathways involving metabolic function and physical indicators. These findings should be interpreted as correlational and cannot establish causality. They highlight the importance of integrated lifestyle management and early metabolic risk assessment for the prevention of hypertension and diabetes in community settings.