Osteoarthritis: New Anti-Obesity Drugs Benefit Healthcare

For those with weight issues and knee osteoarthritis, losing weight is one of the key factors in reducing pain, improving joint function, and slowing the progression of the condition. Diet and exercise can help, but they're often not enough. And new anti-obesity drugs are expensive, making them unaffordable for all patients who need them. Would it be beneficial for the health system to reimburse them at least for those with knee problems? This is the question explored by a study published in the Annals of Internal Medicine , which concluded that of the two GLP-1 analogues currently available for weight loss, tirzepatide has a more advantageous cost-benefit profile (though not exactly stellar due to its still-high prices) in patients with knee osteoarthritis.

The American example

The research is a so-called pharmacoeconomics study, designed to evaluate whether one or more therapies provide sufficient health benefits to justify their cost to the national health system. It was conducted by examining the American market, which has different pricing and organization than our National Health Service. However, the results nevertheless provide an idea of ​​the benefits that anti-obesity drugs can provide to patients with knee arthritis, even in our region (where drug costs are typically lower than in the US).

"Weight loss can improve joint pain, but semaglutide and tirzepatide are expensive, and many insurance companies don't cover these weight-loss drugs. As a result, many patients can't afford them," explains Elena Losina , an orthopedic surgeon at Brigham and Women's Hospital in Boston who led the research. "This is why a formal economic analysis can be valuable: it provides treatment providers and policymakers with the data they need to make informed decisions about reimbursement and improve access to these anti-obesity treatments."

The results

The research was conducted using a program called Oapol, which allows simulations to assess the impact of risk factors, such as obesity, on the epidemiology of osteoarthritis and the disease's impact on patients. It also assessed the potential impact of the two drugs and bariatric surgery, compared to simple lifestyle changes (including diet and exercise), and thus their cost-effectiveness.

The results showed that of the two molecules, tirzepatide appears to be the more cost-effective option, with a cost-effectiveness that could be considered affordable in the American healthcare system (though it would not be so in more frugal public systems, such as the British one). Bariatric surgery appears to be even more cost-effective, but due to its highly invasive nature, it is not a suitable solution for all patients.

"Osteoarthritis substantially reduces patients' quality of life, due to the debilitating pain it causes and the impact it has on their mobility," concludes Losina. "Obesity, for its part, has been shown to reduce life expectancy. Offering the two drugs to patients with knee osteoarthritis and obesity improves both outcomes."