Knee osteoarthritis (OA) is caused and worsened by obesity, as both mechanical stress and obesity-induced inflammation accelerate joint destruction. Weight loss improves knee OA, with studies showing a 2% improvement in the WOMAC pain, function, and stiffness scores for every 1% reduction in body weight. To evaluate the effects of Wegovy-induced weight loss on knee OA (based on clinical and X-ray findings), researchers randomized 407 patients (82% female | average age 56) with a BMI of 30 or greater and moderate knee OA to Wegovy (target dose 2.4 mg/week) or placebo. The primary outcomes were percent change in body weight and change in the WOMAC pain score (scale 0 - 100, with higher scores meaning worse outcomes) at week 68. At baseline, the average BMI was 40.3 and the average WOMAC score was 70.9. After 68 weeks, the percent decrease in body weight was 13.7% in the Wegovy group and 3.2% in the placebo group (p<0.001). Reductions in the WOMAC pain score were superior with Wegovy (41.7 vs 27.5, p<0.001), as were measures of knee function. Drug discontinuations due to adverse events were slightly higher in Wegovy-treated patients (6.7% vs 3%).

As expected, Wegovy-induced weight loss improved knee pain and function in a predominantly female population (82%) with moderate knee OA. A missed opportunity in the study was the absence of follow-up imaging to assess for changes in joint pathology.

Wegovy and Zepbound continue to rack up positive studies, as the health benefits of significant weight loss are profound. Other obesity-related conditions improved by GLP therapies include heart failure with preserved ejection fraction, cardiovascular disease, nonalcoholic steatohepatitis, and obstructive sleep apnea.