Disparities in Preoperative Weight Loss and Obesity Treatment Before Total Joint Arthroplasty

Institutions often implement body mass index (BMI) cutoffs for offering total hip arthroplasty (THA) and total knee arthroplasty (TKA). The goals of this study were to determine disparities in preoperative obesity prevalence, obesity treatment utilization, and weight loss efficacy.

Among 21,038 primary THAs and 23,726 TKAs performed between 2002 and 2019, we identified 6,128 patients who had preoperative BMIs ≥ 30 measured one to 24 months before surgery, including 4,953 with available area deprivation index (ADI) information. The mean age was 67 years (range, 19 to 97) with 55% women. The mean BMI was 36 (range, 20 to 69). The ADI was used to analyze socioeconomic status. Univariable and multivariable analyses evaluated the use of nutrition services or bariatric surgery, the likelihood of weight loss, and ADI's potential association with weight loss.

A few patients received preoperative weight loss medications (0.2%), nutrition services (1.6%), and/or bariatric surgery (2.6%). Compared to the best (least deprived) ADI quartile 1, the worse ADI quartiles 3 and 4 were associated with an increased odds of BMI ≥ 40 preoperatively (odds ratio [OR] 1.4, P = 0.01 and OR 1.9, P < 0.01, respectively). Women were associated with an increased odds of BMI ≥ 40 preoperatively (OR 1.6, P < 0.01) and were more likely to receive bariatric surgery (OR = 2.3, P < 0.01). Women had lower odds of losing ≥ five pounds (OR 0.9, P = 0.02).

The BMI cutoffs of 40 before total joint arthroplasty may disproportionately affect women and patients who have lower socioeconomic status. Few patients received preoperative obesity treatment before TKA or THA via medications, nutrition services, or bariatric surgery. An interdisciplinary approach to preoperative weight management is needed to increase the poor utilization of obesity treatment before THA and TKA.