According to the U.S. Department of Census, the number of centenarians could cross the 4 million mark by 2050. Although approximately 40 percent of centenarians are functionally independent, they are among those at the highest risk for disabling arthritis and fractures due to osteoporosis.
With increasing age, the safety and desirability of performing hip and knee replacements (arthroplasty) may be questioned with the idea that health care resources should be spent on those who can potentially benefit from them the most, and such procedures may be too hazardous for elderly patients.
However, there have been few studies on joint replacement among patients older than 90. A new study published in the August issue of Arthritis Care & Research found that hip and knee replacements are very infrequent among this age group, but that they should not be denied to these patients solely because of short-term life expectancy. The study was the largest to date of hip and knee replacements among centenarians.
Led by Eswar Krishnan, MD, MPH, of the University of Pittsburgh, in Pittsburgh, PA, researchers analyzed 10-year data (1993-2002) from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample, the largest hospital discharge data set in the world. Of the 57 million hospitalization records during this period, 41,335 were for centenarians.
The researchers identified 679 total hip replacements and 7 total knee replacements in patients aged 100 or older. "This relatively low frequency of elective surgery might be due to physician and patient judgment that these individuals are at high risk for poor outcomes and that the risk is not offset by the perceived benefit in light of the relatively short life expectancy," the authors state.
Centenarians who underwent hip replacement were at a higher risk for in-hospital mortality than nonagenarians. Among centenarians, however, hospitalization for hip replacement compared to other causes of hospitalization was associated with a lower risk of death.
Although frailty is known to increase with age, some believe that with better medical care only the extremely elderly are suffering its effects. The authors point out that centenarians live to the century mark by delaying or even avoiding many age-related diseases, and that among those suffering from such conditions, many appear to do so with better functional status than younger patients.
As to the question of whether centenarians and nonagenarians are able to reap the benefits of a new hip or knee, a previous study indicated that one-quarter of the centenarian population are cognitively intact and they appear to sustain their mental status over time. Another study found that nonagenarians treated for hip fractures did not have an increased risk of postoperative complications.
Given the increasing trend of joint replacements over the last decade in the U.S. and the growing centenarian population, such procedures are likely to become more commonplace in the elderly population. The authors conclude, "This study provides data that suggest arthroplasty need not be denied to centenarians solely on account of age and the concern of high in-hospital mortality risk."