Educational Inequalities in Post-Hip Fracture Mortality: A NOREPOS Study.

Abstract

Hip fractures are associated with high excess mortality. Education is an important determinant of health, but little is known about educational inequalities in post-hip fracture mortality. Our objective was to investigate educational inequalities in post-hip fracture mortality and to examine whether comorbidity or family composition could explain any association. We conducted a register-based population study of Norwegians aged 50 years and older from 2002 to 2010. We measured total mortality according to educational attainment in 56,269 hip fracture patients (NORHip) and in the general Norwegian population. Both absolute and relative educational inequalities in mortality in people with and without hip fracture were compared. There was an educational gradient in post-hip fracture mortality in both sexes. Compared with those with primary education only, the age-adjusted relative risk (RR) of mortality in hip fracture patients with tertiary education was 0.82 (95% confidence interval [CI] 0.77-0.87) in men and 0.79 (95% CI 0.75-0.84) in women. Additional adjustments for Charlson comorbidity index, marital status, and number of children did not materially change the estimates. Regardless of educational attainment, the 1-year age-adjusted mortality was three- to fivefold higher in hip fracture patients compared with peers in the general population without fracture. The absolute differences in 1-year mortality according to educational attainment were considerably larger in hip fracture patients than in the population without hip fracture. Absolute educational inequalities in mortality were higher after hip fracture compared with the general population without hip fracture and were not mediated by comorbidity or family composition. Investigation of other possible mediating factors might help to identify new targets for interventions, based on lower educational attainment, to reduce post-hip fracture mortality.