Weight loss drug reduces heart attack and stroke risk regardless of weight loss
Semaglutide reduces the risk of heart attack and stroke by 20 per cent, regardless of weight lost, according to the largest study of 17,604 patients.
The drug, the main ingredient in Wegovy, reduced the risk of major adverse cardiac events — including deaths from heart disease, heart attacks or strokes — by 20 per cent, regardless of the weight patients lost.
The findings suggest the drug may have wider benefits beyond weight loss and should not be restricted only to those with the highest body mass index (BMI).
The study, led by researchers at University College London, examined data from 17,604 adults aged 45 and over who were overweight or obese across 41 countries. Half received weekly injections of semaglutide, while the other half were given a placebo.
Previous analysis had already shown semaglutide’s 20 per cent reduction in cardiac events; this follow-up analysis confirmed the benefit remained even when weight loss was minimal.
Even participants who were only mildly overweight — with a BMI of 27, roughly the UK average — saw similar benefits to those with the highest BMI scores.
The benefits were also largely independent of how much weight people lost in the first four months of treatment.
However, a reduction in waist circumference — a measure of abdominal fat — explained about one-third of the observed cardiovascular benefits.
Professor John Deanfield, from UCL’s Institute of Cardiovascular Science, said: “Abdominal fat is more dangerous for our cardiovascular health than overall weight and therefore it is not surprising to see a link between reduction in waist size and cardiovascular benefit.
“However, this still leaves two-thirds of the heart benefits of semaglutide unexplained. These findings reframe what we think this medication is doing.
“It is labelled as a weight-loss jab but its benefits for the heart are not directly related to the amount of weight lost – in fact, it is a drug that directly affects heart disease and other diseases of ageing.”
He added: “This work has implications for how semaglutide is used in clinical practice.
“You don’t have to lose a lot of weight and you don’t need a high BMI to gain cardiovascular benefit. If your aim is to reduce cardiovascular disease, restricting its use to a limited time only and for those with the highest BMIs doesn’t make sense.
“At the same time, the benefits need to be weighed against potential side-effects. Investigations of side-effects become especially important given the broad range of people this medicine and others like it could help.”
The Select trial findings indicate that semaglutide’s cardiovascular effects are likely driven by multiple mechanisms rather than weight loss alone.
While shrinking waistlines contributed to the outcome, most of the heart benefit appears to stem from other biological effects that directly influence cardiovascular pathways.
