Epidemiology and mortality of hip fracture among patients on dialysis: Taiwan National Cohort Study

Abstract

Chronic kidney disease increases the risk for hip fractures. Hip fractures are associated with increased mortality, decreased quality of life, and higher economic burden. To determine whether dialysis modality is associated with a higher incidence of hip fractures in patients with end-stage renal disease (ESRD), we used the Taiwan National Health Insurance Research Database to examine the records of 51,473 patients who began dialysis between 1999 and 2005. The patients were followed until death, transplantation, dialysis cessation, or 31 December 2008. The follow-up period was (mean±SD) 4.14±2.48 years. The cumulative incidence rate of hip fracture was calculated using Kaplan-Meier methods. Predictors of hip fracture were determined using Cox models. During the study period, 1903 patients had a hip fracture. The overall incidence rate of hip fracture was 89.21/10,000 patient-years. Patients on hemodialysis (HD) had a 31% higher incidence of hip fracture than those on peritoneal dialysis (PD) (HR 1.31, 95% CI: 1.01-1.70). Patients ≥65 years old had more than 13 times the risk of a hip fracture than did those 18-44 years old (HR: 13.65; 95% CI: 10.12-18.40). Other factors that increased the risk of a hip fracture were a prior hip fracture (HR: 1.44; 95% CI: 1.15-1.80), osteoporosis (HR: 1.24; 95% CI: 1.07-1.45), DM (HR: 1.66; 95% CI: 1.51-1.83), and liver cirrhosis (HR: 1.37, 95% CI: 1.15-1.64). The overall in-hospital mortality rate was 3.2%. The cumulative survival rates after a hip fracture were 74.6% at one year and only 29.6% at seven years. Our findings supported the notion that being on HD is a risk for hip fracture. Additionally, old age, female gender, a prior hip fracture, osteoporosis, DM and liver cirrhosis were also risk factors for hip fracture in patients with ESRD and undergoing dialysis.

Keywords: Dialysis; End-stage renal disease; Hip fracture; Mortality.