Associations of Social Determinants and Lifestyle Factors With Incidence and Dynamic Progression of Type 2 Diabetes in the Chinese Population

AIMS: To examine stage-specific associations of social determinants and lifestyle with type 2 diabetes (T2D) progression, evaluate potential lifestyle-mediated effects, and identify major social and behavioural contributors in Chinese populations. MATERIALS AND METHODS: 456 846 China Kadoorie Biobank participants without baseline diabetes and related complications were included. Polysocial risk score (PsRS) was derived from seven social risk factors and healthy lifestyle score from five modifiable behaviours. Multi-state models estimated HRs (95% CIs) for transitions from baseline to T2D, subsequently vascular complications (macro- and microvascular), and finally to death. Mediation analysis quantified lifestyle's mediating effects, and component-specific contributions were also assessed. RESULTS: During a median 10.2-year follow-up, higher PsRS showed consistently increased transition risks: each point increase corresponded to 2% higher T2D incidence (HR: 1.02, 95% CI: 1.00-1.05), 6% higher complication risk after T2D diagnosis (1.06, 1.02-1.11), and 18%-25% higher mortality risks. Healthier lifestyle patterns showed inverse associations, with 3%-20% lower risks across transitions. Both scores showed consistent associations with macrovascular but not microvascular complications. Lifestyle mediated 7.45%-14.92% of social risk associations. Education, accommodation stability, and employment were predominant social determinants, while smoking was the most influential behaviour. CONCLUSIONS: Social determinants and lifestyle behaviours show dynamic, stage-specific associations with T2D progression in China, with lifestyle mediating a modest portion of social risks. Integrated strategies addressing both structural social determinants and key lifestyle behaviours are essential for reducing T2D burden and advancing health equity.