Role of Obesity on the Risk for Total Hip or Knee Arthroplasty

TLDR

The study investigated whether obesity levels are associated with subsequent total hip or knee arthroplasty using data from 54,406 patients in the Canadian Joint Replacement Registry. The authors compared registry patients with a 2006 Canadian Community Health Survey sample and quantified relative risk for THA or TKA across BMI categories. Overweight, obese class I–III patients had progressively higher risks of TKA and THA, with class III individuals experiencing 32.73‑fold and 8.56‑fold increases, confirming a strong obesity‑arthroplasty association. Level II prognostic study evidence; see author guidelines for level definitions.

Abstract

We asked whether there was an association between obesity levels and subsequent THA or TKA using data from 54,406 THA and TKA patients entered into the Canadian Joint Replacement Registry. We compared these patients with a sample of the Canadian population using the Canadian Community Health Survey of 2006. We analyzed information from the Canadian Joint Replacement Registry to quantify the relative risk for THA or TKA in Canada for specific body mass index categories. In reference to the acceptable weight category of body mass index less than 25 kg/m2, the risk for TKA and THA was 3.20- and 1.92-fold higher, respectively, for overweight individuals (body mass index 25-29.9 kg/m2); 8.53- (TKA) and 3.42-fold (THA) higher for those in the obese Class I (body mass index 30-34.9 kg/m2) category; 18.73- (TKA) and 5.24-fold (THA) higher for those identified in obese Class II (body mass index 35-39.9 kg/m2); and 32.73- (TKA) and 8.56-fold (THA) higher for people in obese Class III group (body mass index > 40 kg/m2). Thus, our data support an association between obesity and subsequent THA and TKA. Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.