Latent class trajectories of socioeconomic position over four time points and mortality: the Uppsala Birth Cohort Study

Abstract

Background: The study assessed socioeconomic position (SEP) over four time points and employed a latent class analysis (LCA) to explore the associations between longitudinal SEP trajectories and late-life mortality. Methods: We analyzed a cohort of 11 336 members born at the Uppsala University Hospital, Sweden during 1915-29 and followed up for mortality during 1980-2008. SEP was measured at birth, age 10, mid-adulthood and late adulthood. LCA was used to identify SEP trajectories, which were linked to all-cause and cause-specific mortality through Cox proportional hazard regression models. Results: The age and birth cohort adjusted hazard ratio (HR) of all-cause mortality among the upwardly mobile from middle vs. stable low SEP was 28% lower in men [HR: 0.72; 95% confidence interval (95% CI): 0.65, 0.81] and 30% lower in women (HR: 0.70; 95% CI: 0.62, 0.78). The corresponding HR of cardiovascular mortality was 30% lower in men (HR: 0.70; 95% CI: 0.60, 0.82) and 31% lower in women (HR: 0.69; 95% CI: 0.58, 0.83). Upward mobility was also associated with decreased HR of mortality from respiratory diseases and injuries among men and from cancer, respiratory diseases, injuries and mental disorders among women. The upwardly mobile were similar to the stable high group in terms of their HRs of mortality from all-causes and cardiovascular, cancer and mental diseases. Conclusions: Upward mobility appeared to be protective of mortality from a wide range of causes. Interventions aiming to prevent deaths can benefit from creating optimal conditions earlier in the life course, letting disadvantaged children maximize their socioeconomic and health potentials.