Association of socioeconomic status transition with arthritis: a life-course study

Abstract

Childhood socioeconomic status (SES) and adulthood SES have independent effects on health outcomes. However, the varied effects of SES transition throughout the life course on arthritis remain underrecognized. This study aimed to investigate the association of SES transition with arthritis. Data of this study were obtained from the China Health and Retirement Longitudinal Study in 2011–2020 and the Life History Survey in 2014. Participants aged ≥ 45 years and without arthritis at baseline were followed up for the occurrence of arthritis. Latent class analysis was conducted to identify different levels of childhood SES and adulthood SES. Four SES transition patterns (stable high, downward, upward, and stable low SES) were identified. The Cox proportional hazards model was utilized to elucidate the association between SES and arthritis. Multiplicative and additive interaction analysis, as well as joint analysis, were used to illustrate the interactions among SES, age, gender, resident type, current smoking status, and obesity. Of the 5148 participants, there were 1556 (30.23%) cases of arthritis. Compared with those with high childhood SES, low childhood SES was associated with a higher hazard of arthritis (HR: 1.31, 95% CI: 1.11, 1.55). Compared with those with stable high SES, upward SES transition (HR: 1.45, 95% CI: 1.11, 1.89) and stable low SES transition (HR: 1.59, 95% CI: 1.26, 2.01) were associated with a higher hazard of arthritis. There were joint associations of SES and sociodemographic characteristics with arthritis. There was an increased risk of arthritis due to interaction on an additive scale between childhood SES, SES transition and gender, while there were no statistically significant multiplicative interactive associations of SES and sociodemographic characteristics. Low childhood SES, upward and stable low SES transition were related to the increased risk of arthritis. The findings highlight the importance of mitigating SES inequalities to delay the development of arthritis, which will prompt the goal of healthy longevity and the achievement of sustainable development.