Taking GLP-1 drugs for diabetes has been shown to lower the risk of adverse heart events, but a new analysis found that going off the medication – even for a few months – may increase the odds of heart attack, stroke or death.

“Stopping GLP-1 drugs can rapidly erode and potentially reverse the cardiovascular protection these medications provide,” said study leader Dr. Ziyad Al-Aly of the Veterans Affairs Saint Louis Health Care System in Missouri. “Months of stopping can undo years of progress.”

Researchers studied more than 333,000 adults who were treated for Type 2 diabetes with either GLP-1 drugs or an older class of medications called sulfonylureas, using three years of medical records in a U.S. VA database.

GLP-1 diabetes drugs include Ozempic and Victoza from Novo Nordisk and Eli Lilly's Trulicity and Mounjaro.

Patients who stayed on GLP-1s continuously saw an 18% reduction in cardiovascular risk compared to patients taking sulfonylureas. But stopping for as little as six months erased much of that protection, raising risk by 4% compared to continued use. After two years off treatment, cardiovascular risk rose by 22% compared with continuous use, according to a report in BMJ Medicine.

“Restarting the medication helped restore some cardioprotective effects, but only partially,” Al-Aly said.

Many patients cycle on and off these drugs due to side effects, shortages, and cost, he noted.

“When they stop, it's not just weight that comes back. They experience resurgence in inflammation, blood pressure, and cholesterol,” Al-Aly said.

“Weight regain is visible, the metabolic reversal is not. We think of this as a form of metabolic whiplash, and it seems to be detrimental to heart health.”