US medical study on GLP-1 drug treatment raises questions for employer health plans
Stopping or interrupting treatment with GLP-1 medications — commonly used for weight loss and for treating diabetes — has been linked to a significant increase in risk for major cardiovascular events, according to new research.
A large observational study led by Washington University School of Medicine in St. Louis, published March 18 in BMJ Medicine, tracked more than 333,000 US veterans with type-2 diabetes over three years. The researchers reported that patients who discontinued GLP-1 drugs such as semaglutide (Ozempic, Wegovy) or tirzepatide (Mounjaro, Zepound) saw heart protection decline compared with peers who stayed on therapy continuously.
The study didn’t include patients who used GLP-1 drugs solely for weight loss.
For HR leaders in Canada, the emerging message is that obesity and type-2 diabetes behave like lifelong conditions, and decisions about covering GLP-1 drugs now carry clear implications for long-term cardiovascular risk.
Continuous use versus stop-and-start treatment
The Washington University study compared veterans using GLP-1s with those on an older diabetes drug class, sulfonylureas. Among GLP-1 users, treatment continuity appeared critical. People who remained on a GLP-1 throughout the three-year follow-up had a substantially lower risk of major cardiovascular events than those taking sulfonylureas.
However, patients who stopped GLP-1 therapy for extended periods, even for as little as six months, lost much of this risk reduction, and in some cases had outcomes similar to, or worse than, those who had never used the drugs, the university said in a news release.
The analysis also suggested that stopping and later restarting a GLP-1 may not fully restore cardiovascular protection. Benefits seem to build gradually with sustained use but can erode more quickly once the medication is withdrawn. Researchers linked this pattern to rising blood pressure, cholesterol and inflammatory markers, alongside weight regain, after treatment is interrupted.
GLP-1s better for long-term therapy
For HR leaders, the signal is that GLP-1s are functioning more like long-term cardiometabolic therapies than short-term weight‑loss tools. In practice, that means benefit designs built around brief treatment windows or rapid discontinuation may inadvertently increase health risks for some plan members.
“Clinicians should treat adherence to GLP-1 treatment as an important outcome in its own right — not an afterthought,” said senior author Ziyad Al-Aly in the release. “Health systems need plans in place to help people continue their medication indefinitely, recognizing that GLP-1s treat chronic conditions. That includes proactive management of side effects, candid conversations about the long-term nature of treatment, infrastructure to identify and support patients at risk of stopping and addressing the cost barriers that make GLP-1 therapy unsustainable for many.”
Implications for employee health and benefit strategy
In Canada, GLP-1 medications are already a significant driver of drug plan spending — an Alberta Blue Cross report that reviewed new drug and supplemental submissions made to Health Canada in 2025 named such treatments as a major cost of employer-sponsored dug plans, particularly as the drugs are approved for treatment of more conditions. At the same time, cardiovascular disease remains a leading source of disability, absenteeism and early retirement. Against this backdrop, evidence that heart benefits can fade within months of stopping GLP-1s creates a complex risk-cost trade-off for employer plans.
If coverage is structured so that employees lose reimbursement once they hit a target weight or reach an arbitrary time cap, many will not be able to afford continued therapy. That can set up a cycle of weight regain, deteriorating metabolic health, and renewed cardiovascular risk in mid-career employees. Downstream, organizations may see higher rates of heart attack and stroke, more time away from work, and pressure on life, disability and stop-loss programs.
Coverage policies that treat GLP-1s as purely cosmetic may also widen inequities. Higher-income workers are more likely to self-fund treatment once plan limits are reached, while lower-income employees, who often carry more cardiometabolic risk, may be forced to stop abruptly.
Public coverage for GLP-1 drugs in Canada remains variable, with most provincial plans focusing on diabetes indications and applying tighter restrictions to obesity treatment. As a result, employer-sponsored benefits are a primary route to access for many working-age adults who have obesity but not yet advanced cardiovascular disease.
