Hip Replacement Leads to Improved Physical Functioning in Older Patients

By Todd Neale

DURHAM, N.C., 20 june 2008-- Osteoarthritic hips even in older Medicare patients are likely to respond to arthroplasty with invigorated physical functioning, researchers here found.
Medicare beneficiaries who underwent total-hip arthroplasty were about twice as likely to report improvement in mobility and in the ability to perform the activities of daily living (P<0.01 )
as those who didn't, Linda George, Ph.D., of Duke, and colleagues reported in the June issue of the Journal of the American Geriatrics Society.
Age did not have a significant effect on either of those measures, and in general, participants who did not receive a hip replacement worsened.
"We found that total-hip arthroplasty improves everyday life for patients and is as beneficial to people in their 80s or 90s as it is for someone in their 60s," Dr. George said.
"Physicians are less likely to present this option to the very old," Dr. George said, citing the long rehabilitation time, "but they should feel confident in recommending this procedure to those who are eligible for it."
In general, they said, those who did not receive a hip replacement worsened. Beneficiaries ages 85 and older (P<0.05) and Medicaid recipients (P=0.01) were significantly less likely to receive total hip arthroplasty.
Although the joint-specific benefits and safety of total-hip arthroplasty are well known, its effects on overall physical functioning have been less clear, the researchers said.
So they evaluated data from the Medicare Current Beneficiary Survey from 1992 through 2003 on patients who were diagnosed with osteoarthritis of the hip and who had received total hip arthroplasty (131) or no treatment (257).
All participants were interviewed at baseline and at least six months later. The average interval between interviews was about 13 months in the treatment group and about 15 months for the no-treatment group.
The researchers asked the participants to assess the level of difficulty in performing three items from the Nagi Disability Scale -- stooping or crouching, walking two to three blocks, and lifting objects weighing up to 10 pounds.
They also evaluated the level of difficulty the participants had in performing various instrumental activities of daily living -- light and heavy housework, meal preparation, and shopping -- and activities of daily living -- bathing, getting dressed, sitting, walking, and using the toilet.
Those who had no difficulty walking (P=0.01) or stooping (P=0.001) at baseline were more likely to be in the no-treatment group.
Those who had difficulty lifting, walking, dressing, or using the toilet at baseline were significantly more likely to receive a hip replacement (P<0.05 for all).
Compared with participants who did not receive treatment, those who did had significantly improved physical functioning according scores on the disability assessment and the activities of daily living evaluation.
Those who did not receive a hip replacement had worse physical functioning on follow-up compared with those who underwent the procedure, including statistically significant worsening in the ability to stoop, walk, or shop (P<0.05 for all).
In a logistic regression analysis, having a total hip replacement significantly predicted improvements on the Nagi measures of disability (OR 2.07, 95% CI 1.19 to 3.58) and in the ability to perform the activities of daily living (OR 1.90, 95% CI 1.11 to 3.24) (P<0.01 for both).
Participants who were diagnosed with osteoporosis were significantly less likely to show improvement in disability (OR 0.41, 95% CI 0.21 to 0.79) or instrumental activities of daily living (OR 0.55, 95% CI 0.35 to 0.84) (P<0.01).
Obese participants were less likely to have improved performance in activities of daily living (OR 0.42, 95% CI 0.22 to 0.82, P<0.01).
"These results suggest that effective treatment for osteoporosis and successful strategies for weight control can have positive effects for joint replacement as well as overall health," the researchers said.
The authors acknowledged that the study was limited by the self-reported data and small sample size. With a larger sample, they said, more of the coefficients may have reached statistical significance.
Also, they said, a longer interval between baseline and follow-up would allow for an assessment of the long-term effects of total hip arthroplasty.
The study was supported by a grant from the Institute for Health Technology Studies. The authors reported no conflicts of interest.
Primary source: Journal of the American Geriatrics SocietySource reference:George L, et al "The effects of total hip arthroplasty on physical functioning in the older population" J Am Geriar Soc 2008; 56: 1057-1062.