The Main Cause of Death Following Primary Total Hip and Knee Replacement for Osteoarthritis:A Cohort Study of 26,766 Deaths Following 332,734 Hip Replacements and 29,802 Deaths Following 384,291 Knee Replacements

BACKGROUND: Patients undergoing primary total joint replacement are selected for surgery and thus (other than having a transiently increased mortality rate postoperatively) have a lower mortality rate than age and sex-matched individuals do. Understanding the causes of death following joint replacement would allow targeted strategies to reduce the risk of death and optimize outcome. We aimed to determine the rates and causes of mortality for patients undergoing primary total hip or knee replacement compared with individuals in the general population who were matched for age and sex. METHODS: We compared causes and rates of mortality between age and sex-matched individuals in the general population (National Joint Registry for England, Wales and Northern Ireland; Hospital Episode Statistics; and Office for National Statistics) and a linked cohort of 332,734 patients managed with total hip replacement (26,766 of whom died before the censoring date) and 384,291 patients managed with primary total knee replacement (29,802 of whom died before the censoring date) from 2003 through 2012. RESULTS: The main causes of death were malignant neoplasms (33.8% [9,037] of 26,766 deaths in patients with total hip replacement and 33.3% [9,917] of 29,802 deaths in patients with total knee replacement), circulatory system disorders (32.8% [8,784] of the deaths in patients with total hip replacement and 33.3% [9,932] of the deaths in patients with total knee replacement), respiratory system disorders (10.9% [2,928] of the deaths in patients with total hip replacement and 9.8% [2,932] of the deaths in patients with total knee replacement), and digestive system diseases (5.5% [1,465] of the deaths in patients with total hip replacement and 5.3% [1,572] of the deaths in patients with total knee replacement). There was a relative reduction in mortality (39%) compared with the individuals in the general population that equalized to the rate in the general population by 7 years for hips (overall standardized mortality ratio [SMR], 0.61; ...