Prevalence and distribution of hip and knee joint replacements and hip implants in older Americans by the end of life

Abstract

Background and aims: Hip and knee replacements have become increasingly common in the older population but the prevalence of these procedures and the potential impact on functioning towards the end of life have not been previously described. The aim of this study was to estimate the rates and distribution of hip and knee joint replacements and hip implants (surgical pins, screws, rods, plates, etc.) in people aged 65 and over who died in the US in 1993, and to measure mobility outcomes during their last year of life.

Methods: Data were drawn from the 1993 National Mortality Followback Survey; 7684 deaths in people aged 65 years or over were included. From these data full informant interviews were available for 6586 (86%). Three hundred and forty-four decedents had hip joint replacements, 357 had hip implants, and 102 had knee joint replacements. Replicate methods were used to obtain weighted estimates for all decedents in the 1993 US base population.

Results: Of female and male decedents, 15.5% (95% CI: 14.3-16.7) and 6.1% (95% CI: 3.9-8.2), respectively, had received the studied devices. About 80% of these had been implanted more than a year before death. There were large differences in the risks of receiving a hip joint replacement or a hip implant depending on gender, education and race. About 60% of recipients either had no difficulty in getting around their own homes during the last year of life or had difficulty lasting less than 6 months.

Conclusions: Implanted hip and knee devices were common in older people who died in the US in 1993. Large sociodemographic differences in those who received vs those who did not were present at the end of life. While difficulty in walking is the main indication for joint replacements, a majority of those receiving replacements experienced less than 6 months of mobility difficulties in their own homes during the last year of their lives.