Long-term excess mortality after hip fracture in hemodialysis patients: a nationwide cohort study in Japan

J Bone Miner Metab. 2020 Sep;38(5):718-729. doi: 10.1007/s00774-020-01110-4. Epub 2020 May 12.

Abstract

Introduction: Fracture dialysis patients have a higher risk of 1-year mortality compared with non-fracture dialysis patients. However, it is unclear whether excess mortality persists for more than a year.

Materials and methods: We conducted a nationwide cohort study in 162,360 hemodialysis patients in Japan. Study outcomes were 5-year all-cause mortality and cause-specific mortality. Cox proportional hazards regression was used to examine the association between hip fracture and mortality in two cohorts: the full cohort, which included potential confounders as covariates in multivariable-adjusted regression models, and the propensity score-matched cohort.

Results: Crude mortality rates for fracture patients were double those of non-fracture patients and persisted during the 5-year period. The association between hip fracture and mortality was significant even after adjusting for premorbid conditions (hazard ratio (HR) 1.22, 95% confidence interval (CI) 1.13-1.32). Similar findings were observed in the propensity score-matched cohort of 2410 patients (HR 1.20, 95% CI 1.05-1.36). While cause-specific mortality rates for all categories, with the exception of sudden deaths, were higher for fracture patients relative to non-fracture patients in the full unmatched cohort, only the mortality rate for heart disease was significantly higher for fracture patients relative to non-fracture patients in the propensity score-matched cohort.

Conclusion: Excess mortality persisted for many years after hip fracture in hemodialysis patients, and was still present after adjusting for several premorbid conditions and propensity score matching.

Keywords: Cardiovascular; Dialysis; End-stage kidney disease; Hip fracture; Mortality risk.

MeSH terms

  • Aged
  • Cause of Death
  • Cohort Studies
  • Female
  • Hip Fractures / mortality*
  • Humans
  • Japan / epidemiology
  • Kaplan-Meier Estimate
  • Male
  • Propensity Score
  • Proportional Hazards Models
  • Renal Dialysis / mortality*