Does Obesity Treatment With Liraglutide Reduce Ectopic Fat?Tuesday, August 17, 2021
Clinical trials have consistently documented the weight-loss effect of treatment with the GLP-1 analogue liraglutide. These studies have also generally reported a significant reduction in waist circumference, a simple surrogate measure for visceral obesity.
But, does this finding hold up with more precise measures of ectopic fat?
That is apparently the case, based on a study by Ian Neeland and colleagues published in The Lancet Diabetes and Endocrinology.
The researchers randomised 185 volunteers with a BMI of at least 30 kg/m2 or BMI of at least 27 kg/m2 with metabolic syndrome but without diabetes to 40 weeks of treatment with once-daily subcutaneous liraglutide 3·0 mg or placebo, in addition to a 500 kcal deficient diet and guideline-recommended physical activity counselling.
At the end of the trial, visceral adipose tissue, assessed with MRI, was reduced by 12.5 % with liraglutide compared to 1.6% with placebo. Interestingly, this difference was substantially underestimated by changes in waist circumference, which only reduced by 7% with lirgalutide vs. 4% with placebo.
Perhaps, even more remarkably, while liver fat reduced by 12% with liraglutide, it actually increased by 21% in the placebo group.
Adverse effects were typical of those expected with liraglutide (largely transient GI-related).
Thus, the authors note that,
“The relative effects of liraglutide on fat reduction were two-times greater in the abdominal viscera and six times greater in the liver than seen on overall bodyweight. The treatment effect seemed consistent across race–ethnicity and baseline BMI categories, and among those with or without baseline prediabetes”
“Although individual body fat depot reductions were highly correlated with overall bodyweight loss, VAT, and to a greater degree liver fat, were less well correlated with weight loss. This could suggest a partially weight-independent effect of GLP-1 receptor agonism on body fat distribution.”
In summary, it certainly appears reassuring that treatment with liraglutide indeed results in a marked reduction in visceral and ectopic fat, as these fat depots have been associated with increased metabolic and cardiovascular risk.
Disclaimer: I have received honoraria as a consultant and speaker from Novo Nordisk, the maker of liraglutide.