Social determinants of health and lifestyle in the progression of degenerative bone and joint diseases: a prospective multi-state analysis

Abstract

Abstract Aims The role of social determinants of health (SDOH) in the progression of degenerative bone and joint diseases (DBJDs) - from initial onset to multimorbidity and mortality - remains unclear. We aimed to assess the associations of SDOH with DBJDs progression, examine the mediating role of lifestyle, and explore their joint effects. Methods A total of 283,146 participants from the UK Biobank were included. SDOH was constructed using 17 items including economic, education, healthcare, neighbourhood, and social domains, and categorized into favourable, intermediate, and unfavourable groups. The outcomes of interest were first DBJD (FDBJD), DBJM (the coexistence of at least two DBJDs), and all-cause mortality. Multi-state models were employed to estimate risks across five disease transitions. Results During a median follow-up of 13.7 years, 43,172 participants developed FDBJD, of whom, 4,170 subsequently developed DBJM, and 18,831 died. Compared with favourable SDOH, unfavourable SDOH was associated with increased risks of all transitions, including from baseline to FDBJD (HR = 1.21, 95%CI = 1.18–1.24), from baseline to death (1.58 [1.52–1.65]), from FDBJD to DBJM (1.33 [1.23–1.44]), from FDBJD to death (1.64 [1.50–1.80]), and from DBJM to death (1.48 [1.17–1.87]). Economic stability and social and community context emerged as the most robust predictors. Lifestyle factors partially mediated the associations, with proportions of mediation ranging from 2.47% to 10.77%. Participants with unfavourable SDOH and lifestyle exhibited the highest risks, with significant additive interactions observed in transitions of death from baseline or after FDBJD. Conclusions Unfavourable SDOH are strongly associated with progression and mortality of DBJDs, with effects that extend beyond individual lifestyle factors. These findings underscore the importance of addressing upstream social determinants, alongside lifestyle promotion, to reduce the burden of DBJDs and social inequalities in musculoskeletal health.