New Haven, Conn. — Expanding access to new, highly effective weight-loss medications could prevent more than 40,000 deaths a year in the United States, according to a new study led by researchers at Yale School of Public Health and the University of Florida.

The findings highlight the critical need to remove existing barriers that are hindering people’s access to effective weight loss treatments and impeding public health efforts to address the national obesity crisis, the researchers said. According to the U.S. Centers for Disease Control and Prevention, about 74% of Americans are considered overweight, with about 43% of those individuals considered obese.

Obesity's widespread impact on health is well-documented. It exacerbates conditions such as type 2 diabetes, cardiovascular disease, and certain cancers. Yet, despite its severe consequences, the development and deployment of highly effective treatments for obesity have been lacking. Recent advancements in pharmaceutical interventions however, particularly the introduction of glucagon-like peptide-1 (GLP-1) receptor agonists, such as Ozempic and Wegovy, and dual gastric inhibitory polypeptide and GLP-1 (GIP/GLP-1) receptor agonists, such as tirzepatide, have demonstrated substantial efficacy in weight loss. These medications have shown promise in clinical trials and are increasingly being used for weight management.

In conducting their study, the researchers aimed to quantify the potential mortality impact of increased access to these weight-loss drugs. They integrated data on mortality risk associated with different body mass index (BMI) categories, obesity prevalence, and the current limitations on drug access due to high costs and insurance restrictions.

According to the findings, if access to these new medications were expanded to include all eligible individuals, the U.S. could see up to 42,027 fewer deaths annually. This estimate includes approximately 11,769 deaths among individuals with type 2 diabetes — a group particularly vulnerable to the complications of obesity. Even under current conditions of limited access, the researchers project that around 8,592 lives are saved each year, primarily among those with private insurance.

The study highlights a critical disparity in drug access. Currently, the high cost of these medications, which can exceed $1,000 per month without insurance, limits their availability. For example, Medicare — one of the largest insurance programs for older adults — does not cover these drugs for weight loss, impacting many who could benefit from them. Medicaid coverage varies widely by state, and private insurance often imposes high deductibles and copays, further restricting access, the researchers said.

"Expanding access to these medications is not just a matter of improving treatment options but also a crucial public health intervention," said Alison P. Galvani, one of the study's corresponding authors and the Burnett and Stender Families Professor of Epidemiology (Microbial Diseases) at the Yale School of Public Health. "Our findings underscore the potential to reduce mortality significantly by addressing financial and coverage barriers."

The study also explored how expanded access could affect different regions and socioeconomic groups. States with high obesity and diabetes rates, such as West Virginia, Mississippi, and Oklahoma, stand to benefit the most from increased medication availability. In these areas, expanding access could lead to the largest per capita reductions in mortality.

However, the study's authors caution that while the potential benefits are substantial, several challenges remain. The high price of these medications is a significant barrier, and there are concerns about the pharmaceutical industry's profit margins. Furthermore, supply constraints and production limitations continue to hamper widespread availability.

"Addressing these challenges requires a multifaceted approach," said Dr. Burton H. Singer, PhD, another corresponding author of the study and adjunct professor of mathematics at the Emerging Pathogens Institute at the University of Florida. "We need to ensure that drug prices are more aligned with manufacturing costs and increase production capacity to meet demand. At the same time, we must tackle the insurance and accessibility issues that prevent many people from getting the treatment they need."

The researchers also considered the impact of socioeconomic factors on the effectiveness of expanded drug access. They adjusted their estimates to account for income disparities, finding that even with these adjustments, the potential for lives saved remains significant. The results suggest that improving access to these medications could reduce health care costs associated with obesity-related conditions and improve overall quality of life for many Americans.

The study appears in the peer-reviewed journal Proceedings of the National Academy of Science.

Abhishek Pandey, a research scientist at the Yale School of Public Health, is lead author of the study. Yale postdoctoral research associates Yang Ye and Chad R. Wells are coauthors.