Background/Purpose: US federal law currently does not allow Medicare Part D coverage for weight loss medications without additional indications, such as diabetes. Several glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have been approved for weight loss alone. GLP-1 RAs are prohibitively expensive, and only about 1% of Medicare beneficiaries report taking GLP-1 RAs for weight loss. The substantial clinical benefits associated with GLP-1 RAs in RCTs, coupled with their high cost, have led to discussions about adding Medicare coverage for weight loss indications. We examined the potential public health impact of expanding coverage of GLP-1 RAs for weight loss among Medicare Part D beneficiaries with knee osteoarthritis (OA) and obesity.

Methods: We used the data from OAI (the Osteoarthritis Initiative), the United States Census, NHANES (National Health and Nutrition Examination Survey) and published literature to estimate the proportion of the US population ≥65 years of age with obesity (BMI ≥30 kg/m2) and knee OA, without type 2 diabetes mellitus (T2DM), and enrolled in Medicare Part D. Using the Osteoarthritis Policy Model (OAPol), a widely published and validated microsimulation of OA, we estimated the maximum potential clinical benefits of GLP-1 RAs coverage for weight loss among Medicare beneficiaries with knee OA and obesity as the difference in clinical outcomes with and without GLP-1 RA use. The clinical benefits included gains in life expectancy and gains in quality-adjusted life expectancy along with reductions in incident cases of MACE, T2DM, and total knee replacement (TKR). We modeled GLP-1 RA weight loss efficacy, toxicity and discontinuation rates from the SURMOUNT trials. We derived knee pain reduction using data from the STEP-9 trial, which focused on a population with knee OA. To recognize that not all eligible Medicare beneficiaries would use GLP-1 RAs for weight loss, we used data for GLP-1 RA uptake among people with GLP-1 RA insurance coverage to estimate realistic clinical benefits (~20% uptake among those who are eligible).

Results: We estimated that 591,550 Americans have obesity, symptomatic knee OA, no T2DM, and are enrolled in Medicare Part D. Cumulatively, affordable access to GLP1RA among this entire population would add 319,824 years to life expectancy (0.54/person) and 341,827 years to quality-adjusted life expectancy (0.58/person), if every eligible individual would use GLP-1 RAs. Additionally, expanded GLP-1 RA coverage could avert 39,893 cases of T2DM, 6,745 major adverse cardiovascular events (MACEs, including 2,173 CVD-attributable deaths), and 6,380 TKRs. Table 1 shows maximum and realistic health gains for scenarios of GLP-1 RA uptake.

Conclusion: Adding GLP-1 RA coverage for weight loss alone to Medicare Part D may lead to substantial health benefits in the US, increasing survival and improving quality of life, while also averting costly and morbid chronic diseases and reducing the need for TKR, even if only parts of this population would be willing to use these medications. These estimates may be useful when discussing how to balance the health benefits of expanded access to GLP-1 RAs with the potential budgetary impacts.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/model-based-evaluation-of-the-potential-public-health-impact-of-expanding-medicare-coverage-for-weight-loss-medications-for-beneficiaries-with-knee-osteoarthritis-and-obesity-in-the-us/