Aon released updated findings from its multi-year study of US commercial health claims, expanding on GLP-1 research first published in April 2025. The latest analysis draws on medical and pharmacy claims covering more than 192,000 GLP-1 users and points to a combination of long-term cost moderation and meaningful clinical benefits.
The study shows sustained use of GLP-1 therapies reduces medical cost growth over time for employers while improving health outcomes across the workforce.
Among women, the effects appear pronounced. Female GLP-1 users recorded a 47% reduction in hospitalisations linked to major cardiovascular events, roughly a 50% lower incidence of ovarian cancer, and a 14% lower incidence of breast cancer compared with female non-users.
According to Aon, these results carry implications for workforce health strategies, particularly in sectors with large female populations and elevated chronic disease exposure.
Lisa Stevens said obesity, diabetes, and cancer remain among the most pressing challenges facing employees and employers alike. She said the findings point to the ability of GLP-1 therapies to materially improve health outcomes, with women seeing especially strong reductions in cardiovascular and cancer risks.
The analysis is based on Aon’s proprietary cost efficiency measurement methodology and its health risk analytics tools.
Researchers evaluated claims data from more than 50 mn commercially insured lives between July 2022 and March 2025, isolating outcomes for individuals prescribed GLP-1 therapies.
For diabetes patients, medical cost growth ran six percentage points lower than non-users after 30 months, and nine points lower for those maintaining adherence of at least 80%.
Similar patterns appeared among users prescribed GLP-1s for weight management, where cost growth fell three percentage points at 18 months and seven points among consistent users.
Beyond cost trends, the data suggests broader clinical effects.
Female GLP-1 users showed lower rates of ovarian and breast cancer, alongside reduced incidence of osteoporosis, rheumatoid arthritis, and fewer hospitalisations tied to substance abuse, bariatric surgery, and certain pancreatic disorders.
Cardiovascular outcomes also diverged sharply. Among users with high adherence, hospitalisations for major adverse cardiovascular events fell significantly, with a 47% reduction observed in women compared with 26% among men.
Farheen Dam said the findings give employers clearer visibility into how GLP-1 therapies influence both long-term health risk and cost trajectories. She said outcomes depend less on access alone and more on how these medications are supported and used over time, arguing that adherence and broader wellbeing programmes shape the real return.
The findings land as employers grapple with accelerating healthcare costs. Aon projects underlying US employer healthcare costs will rise 9.5% in 2026.
Prescription drugs now account for about 30% of total healthcare spend, growing at an annual pace of roughly 13% to 15%. GLP-1 therapies drive a large share of that increase, representing about 20% of total prescription drug costs, with GLP-1 spending rising around 50% during 2025 as utilisation expanded.
Cancer remains a major cost driver, reflecting both rising incidence and increasingly expensive treatments.
Obesity compounds the burden, contributing to more than 60 chronic conditions and driving healthcare costs about 66% higher for affected individuals. Aon estimates obesity costs the US economy up to $1.72 tn each year.
Laura Rissover said the strength of the study lies in its scale and longitudinal design, allowing researchers to observe how total medical costs and outcomes change over time among large cohorts of GLP-1 users.
She said this level of detail helps employers assess health impact alongside financial sustainability when shaping GLP-1 coverage strategies.
Aon plans to present highlights from the analysis at the 2026 World Economic Forum Annual Meeting, where it will host discussions with clients and partners on how GLP-1 therapies are reshaping workforce health, cost management, and long-term wellbeing.
