A year-long clinical trial published in Nature Metabolism suggests that regular exercise, rather than liraglutide medication alone, is key to improving arterial health and reducing inflammation following significant weight loss in adults with obesity, according to a June 25 report.
The study was a prespecified secondary analysis of the S-LiTE trial. Researchers analyzed data from 130 participants who had already lost an average of 13.7 kilograms (about 12.7% of their body weight) through an initial low-calorie diet. Participants were then randomly assigned to one of four groups: placebo only, exercise plus placebo, liraglutide (3.0 mg daily), or exercise plus liraglutide for a period of 52 weeks.
Researchers monitored changes in carotid artery wall thickness (cIMT), inflammatory biomarkers such as interleukin-6 and interferon-gamma, and markers of endothelial function over the intervention period. The results showed that groups including exercise—either with or without liraglutide—experienced significant reductions in cIMT and improvements in inflammatory and endothelial biomarker profiles compared to those receiving medication alone or placebo.
Specifically, cIMT decreased by 7% in the exercise plus placebo group and by 6% in the exercise plus liraglutide group compared with placebo-only participants. Reductions were also seen in inflammatory markers: IL-6 levels dropped by up to 26%, IFNγ levels fell by up to 45%, and there were notable decreases in adhesion molecules linked to vascular health among those exercising regularly.
In contrast, participants treated solely with liraglutide did not see statistically significant improvements in these vascular or inflammatory outcomes relative to the placebo group. The authors noted that while GLP-1 receptor agonists like liraglutide are effective for weight management, they do not substitute for the specific vascular benefits gained from physical activity during weight-loss maintenance.
The researchers caution that these findings should be interpreted carefully due to limitations such as secondary analysis design, use of surrogate endpoints like cIMT, lack of adjustment for multiple comparisons, per-protocol population selection, and partial supervision within the exercise program.
