Secular reduction of excess mortality in hip fracture patients >85 years

Background: More than 20% of the hip fracture patients die within the first year after the incident. Few data are available on the trends in mortality following a hip fracture. The present aim was to study changes in excess mortality after hip fracture from 1978/79 up to 1996/97. Methods: Data on 5180 hip fracture patients aged >= 50 years, identified in three earlier, well validated, incidence studies from Oslo were used. The studies took place in the two years periods 1978-79 and 1989-89 and in a one year period from 1st of May 1996 to 30th of April 1997. The study was designed as a historic cohort study. Exposure was sustaining a hip fracture in the registration periods. Outcome was death of all causes. Age- and sex-specific one year-mortality rates were provided by Statistics Norway. Standardized mortality ratios (SMR) were calculated for the three cohorts for each sex and age-group, for the 0-6 months, 6-12 months, 0-1 year, 1-5 years and 5-10 years intervals after fracture. To assess the duration of the excess mortality in hip fracture patients, time-framed Kaplan-Meier curves for consecutive 5-years intervals were conducted for the hip fracture patients and the corresponding background population. Only patients still alive at the start of the time interval were included. One sample log rank tests were used to test for statistical significance. Results: The one-year SMR ranged from 3.64 (2.82 - 4.61) to 4.53 (3.67 - 5.54) in men and from 2.78 (2.39 - 3.19) to 3.60 (3.19 - 4.05) in women. In the 0-6 months interval a reduction in SMR from 1978/79 to 1996/97 was observed in women aged >= 85 years. The duration of excess mortality ranged from two years in men >= 85 years to more than ten years in men and women aged 65-84 years. Conclusion: Excess mortality among hip fracture patients remains high. Over the decades, a reduced excess mortality was mainly seen in the oldest patients, suggesting that specific efforts intending to improve prevention and treatment of osteoporosis and osteoporotic fractures in the youngest elderly are required.