The Association Between Obesity and Disability in Survivors of Joint Surgery: Analysis of the Health and Retirement Study

Abstract [from journal]

Background
Obesity is associated with osteoarthritis and the need for joint surgery. Obese patients who undergo joint surgery may have a higher risk of morbidity compared with normal or overweight patients but less is known about their risk of postoperative disability. The primary objective of our study was to determine the association between obesity and the development of new dependence in activities of daily living within 2 years after joint surgery.

Methods
We obtained data from the Health and Retirement Study, a longitudinal survey of older Americans. We included participants who indicated having joint surgery for arthritis. We defined obesity as a BMI ≥30 kg m-2. Our outcome was a new or increased dependence in one or more activities of daily living after surgery.

Results
We analysed data on 2519 respondents who underwent joint surgery for arthritis. Respondents had a median age of 69yr, 65.5% were female, 66.6% had joint replacement surgery and 45.3% were obese. The overall incidence of a new dependence within 2 years was 22.1%. Obese respondents had a higher incidence of new dependence compared with non-obese respondents (25.4% vs 19.4%, P<0.001). In adjusted analysis, obese respondents had increased odds of developing dependence [odds ratio 1.35 (95% CI 1.09-1.68), P=0.007].

Conclusions
Obesity is associated with an increased risk of developing dependence in the 2 years after joint surgery. Our study findings identify a high-risk group that may benefit from targeted interventions and allocation of perioperative resources to optimize recovery and minimize longer-term disability.