To the Editor The study by Dr King and colleagues1 concluded that pain and self-reported and objectively measured physical function improved significantly over a period of 3 years following bariatric surgery. A number of relevant factors associated with pain and physical function improvements were identified. However, the authors did not consider the potentially important influence of the patients’ participation in physical activity and exercise during the follow-up period as a factor related to improvement in pain and function. Exercise can enhance weight reduction, reduce pain intensity, and improve self-reported physical function in overweight and obese patients with knee osteoarthritis.2 Furthermore, physical activity in morbidly obese patients following bariatric surgery has been shown to enhance weight loss,3 which might benefit physical function and knee pain.4 Thus, participation in physical activity or exercise programs following bariatric surgery might be associated with improvement in physical function measures such as the 400-m test used by King and colleagues.1 We suggest that future observational studies might benefit from assessing presurgery-to-postsurgery changes in physical activity levels.
Soriano-Maldonado A, Márquez MF, Artero EG. Pain and Physical Function Following Bariatric Surgery. JAMA. 2016;316(7):770. doi:10.1001/jama.2016.8590