Experts Debate the Value of Medical Versus Behavioral Lifestyle Interventions for Patients with Obesity and OA

Obesity is a growing global epidemic and is associated with the incidence and development of osteoarthritis (OA). Prescribing a medication to stimulate weight loss is the most convenient option for patients, but clinicians must look beyond convenience to account for factors such as cost and the long-term welfare of their patients when deciding between behavioral therapies and medical management of OA. 

Experts debated the merits of these distinct therapeutic philosophies during the session Weighing In: A Debate on Medical vs. Behavioral Lifestyle Interventions for People with Obesity and Osteoarthritis on Sunday, Nov. 17. The session will be available on-demand to all registered ACR Convergence 2024 participants after the meeting through Oct. 10, 2025, by logging into the meeting website.

Stephen Messier, PhD, Professor and Director of the J.B. Snow Biomechanics Laboratory at Wake Forest University, presented support that behavioral therapy interventions targeting diet and exercise were the optimal approach to stimulate weight loss for patients living with obesity and OA. In addition to the reduced risk of obesity-related morbidity and mortality, Dr. Messier cited the importance of diet and exercise for pain reduction in patients with OA.

“Intensive weight loss and exercise reduces abnormal stress by decreasing knee joint loads and reduces abnormal physiology by lowering inflammation, resulting in less pain and less disability,” Dr. Messier said.

A study led by Dr. Messier showed that dietary weight loss with exercise reduced pain for patients with knee OA by 51% over 18 months. Each intervention alone reduced pain by half as much as the combination.

Martin Englund, MD, PhD, Professor at Lund University, Sweden, advocated for the use of glucagon-like peptide-1 (GLP-1) receptor agonists to help patients with obesity and OA lose weight.

He shared results from the STEP 1 and SELECT trials, as well as a study analyzing tirzapedtide’s effects on weight loss. Research has shown GLP-1 receptor agonists reduce weight by about 10–15% more than lifestyle interventions and placebo.

Dr. Englund also presented a 2024 study that examined the effects of semaglutide on knee OA pain. The results again showed that the GLP-1 receptor agonist reduced knee OA pain and improved function more than the comparative lifestyle intervention and placebo.

Dr. Messier contended that one of the primary issues with GLP-1 receptor agonists for weight loss was the long-term efficacy of sustained healthy weight management after the drug is stopped.

“There’s a rapid weight regain, with two-thirds of the weight loss regained at one year,” Dr. Messier said.

This data suggests that patients would require lifelong treatment to sustain weight loss with GLP-1 receptor agonists. Dr. Englund acknowledged that patients who experienced weight loss via these agents did show some challenges with regaining weight, but said there shouldn’t be an issue with a lifelong treatment regimen.

“Lifelong treatment is also the case for far more common chronic diseases that can’t be cured, such as hypertension, and we don’t think it’s strange to take a tablet a day for hypertension,” Dr. Englund said.

Dr. Messier also contended that medical interventions are far less cost-effective than lifestyle interventions.

“GLP-1 is expensive. The annual cost of semaglutide is over $16,000, tirzepatide over $12,000, and the annual cost of diet and exercise is only $3,400,” he explained.

While he acknowledged that costs associated with GLP-1 receptor agonists are relatively high, Dr. Englund maintained that the treatments were still cost-effective for weight loss and asserted that the cost of the drugs is expected to be reduced when the correlating patents expire.

Dr. Messier shared his vision for a path forward to increase weight loss with diet and exercise interventions across the United States. He proposed that healthcare insurers take an active role in developing and funding community programs with trained staff with expertise in behavioral therapy techniques.

“These community programs should be based on empirical data from high-quality diet and exercise randomized clinical trials,” Dr. Messier said.

According to Dr. Messier, accountability would be achieved by sharing patient progress with healthcare providers at regular intervals. He also acknowledged that under this plan, each interventionist would have a “behavioral toolbox” that could include GLP-1 receptor agonists as an option.

While Dr. Englund maintained his position on the efficacy of GLP-1 receptor agonists, he concurred with Dr. Messier that lifestyle interventions are critically important for patients with obesity and OA to live a sustained, healthy life.

“Lifestyle changes should naturally always be the foundation,” he said.