General and Abdominal Obesity as Risk Factors for Late-Life Mobility Limitation After Total Knee or Hip Replacement for Osteoarthritis Among Women

Abstract

Objective: To investigate associations of body mass index (BMI), waist circumference (WC), and waist/hip ratio (WHR) with survival to age 85 years with mobility limitation or death before age 85 years among older women with total knee replacement (TKR) or total hip replacement (THR) for osteoarthritis (OA). Methods: This was a prospective study of women (ages 65–79 years at baseline) from the Women's Health Initiative, recruited during 1993–1998 and followed through 2012. Women's Health Initiative data were linked to Medicare claims data to determine TKR (n = 1,867) and THR (n = 944) for OA. Women were followed for up to 18 years after undergoing THR or TKR to determine mobility status at age 85 years. Results: Compared with normal-weight women, overweight, obese I, and obese II women with THR had significantly increased risk of survival to age 85 years with mobility limitation (P < 0.001 for linear trend), with the strongest risk among obese II women (odds ratio [OR] 4.37 [95% confidence interval (95% CI) 1.96–9.74]). Obese II women with THR also had increased risk of death before age 85 years. Women with THR and WC >88 cm relative to ≤88 cm had increased risk of survival to age 85 years with mobility limitation (OR 1.65 [95% CI 1.17–2.33]) but not death before age 85 years. High BMI, WC, and WHR were associated with significantly increased risk of late-life mobility limitation and death among women with TKR for OA. Conclusion: Among older women who underwent THR or TKR for OA, baseline general and abdominal obesity were associated with increased risk of late-life mobility limitation.