GLP-1 medications like Ozempic have been used to treat type II diabetes for two decades. More recently, the drug has been an effective weight loss tool for overweight and obese individuals — so effective it could influence the country’s economy.
Weight loss can have secondary cardiovascular benefits, but new research suggests GLP-1s may have a direct impact on heart health, too, with anti-obesity drugs among the American College of Cardiology’s top five trends in cardiovascular medicine for 2025.
Glucagon-like peptide-1 [GLP-1] medications stimulate the pancreas to release insulin, one of two hormones controlling blood sugar. The other is glucagon. People with type II diabetes struggle to regulate insulin secretion, which can result in elevated blood sugar and a break down of certain biological functions.
That differs from type I diabetes, which requires insulin injections. Type II diabetes is strongly correlated with obesity.
“Some of the newer drugs — like semaglutide, which is known as Ozempic and Wegovy, and tirzepatide, which is known as Mounjaro and Zepbound — these drugs have increased potency. They require less frequent administration,” said Dr. Christopher Sparrow, a cardiologist specializing in heart failure and transplantation at OSF Saint Francis Medical Center in Peoria. “They’re also associated with quite a few less side effects and have an enhanced weight loss benefit.”
A few years ago, GLP-1s surged in popularity as a weight loss drug for overweight and obese individuals regardless of whether they have Type II diabetes. Sparrow said the receptors targeted by GLP-1 medications are primarily in the gut. They’re also in the brain and heart, reducing hunger by stimulating satiety and reducing inflammation that affects heart and cardiovascular function.
“The beneficial effects are very strongly linked to weight loss,” Sparrow said. “In all of the studies, the more weight you lose, the more benefit on your cardiovascular health.”
But the effects of weight loss with GLP-1 medications exceeded those of weight loss alone. The greatest benefit was among people with type II diabetes.
“These patients have been shown to have a reduced risk of heart attack, stroke and cardiovascular death when they use these medications,” said Sparrow.
There also was a benefit among people with pre-existing cardiovascular disease and certain types of heart failure. In that population, subjects were less likely to experience recurrence of cardiovascular events and demonstrated increased heart function and ability to walk further distances.
“The excitement behind this is huge because it opens the door to not only these drugs being used as a preventative strategy for heart disease, but a potential therapeutic to improve outcomes in these patients who have reduced quality of life due to heart failure,” said Sparrow.
There’s not enough data to know whether that could delay or prevent the need for a heart transplant, he said. And the drugs have not been studied among people with weakened heart muscles.
“The Food and Drug Administration [FDA] has not approved these drugs for heart failure yet, but as a heart failure doctor, I’m telling you I’m very much looking forward to the time where we can have access to these therapeutics for a larger population,” Sparrow said.
Access and availability
As various GLP-1 medications grew in popularity, they became harder to get, prompting some companies to produce an over-the-counter compounded version. These medications have the same active ingredients as FDA-approved GLP-1s and are available at a fraction of the cost.
“During the Super Bowl we saw an advertisement directly to consumers for compounded weight loss drugs, basically, without ever having to see a doctor,” Sparrow said. “This is a big hot topic in medicine. It’s in a very ethical and legal gray area.”
Sparrow said compounded medications can be appropriate in some situations, particularly during drug shortages. In December, the FDA renewed its objections of compounded GLP-1s, noting the end of a Zepbound shortage. On Feb. 21, they also said Ozempic supply was keeping up with demand.
The sticker price also keeps the drug out of reach for many, with only about 1 in 5 employer health plans covering GLP-1s. Those who do cover it sometimes make patients jump through additional hoops. State of Illinois employees, for example, that includes Illinois State University, must comply with a weight management program to keep their coverage.
Medicare recently announced it would cover GLP-1 medications for obese patients with cardiovascular disease, impacting about 3.4 million Americans. Adults over 50 are more likely to develop cardiovascular disease.
