Children who are living with severe obesity are more likely to experience a clinically relevant change in BMI when GLP-1 agonist drugs form part of their treatment, new research being presented at year's European Congress on Obesity (ECO 2025) suggests.
Glucagon-like peptide-1 (GLP-1) receptor agonists mimic the action of a hormone called GLP-1 to reduce appetite and feelings of hunger, slow the release of food from the stomach and increase feelings of fullness after eating.
"GLP-1 drugs are increasingly used to treat obesity in adults," says researcher Dr Annika Janson, of the National Childhood Obesity Centre, Karolinska University Hospital, Stockholm, Sweden. "They can also be used in children from the age of 12 and clinical trials have shown children lose 5-16% of their body weight after a year of treatment.
"However, treating children in real-life situations has challenges that don't come up in research studies.
"Children have varying degrees of obesity, co-morbidities and complications and may have faced problems in supply of the drug, financing it or taking it. As a consequence, it is difficult to isolate the effect of adding GLP-1 drugs to the plethora of treatments that are already available."
To find out more, Dr Janson and colleagues examined the impact of adding GLP1- receptor agonists to an existing treatment programme for child obesity.
The study involved 1,126 children (51.6% boys) age 0-16 years with severe obesity, as defined by the International Obesity Task Force criteria1, who were receiving intensive health behaviour and lifestyle treatment (IHBLT) at the National Childhood Obesity Centre in Stockholm.
IHBLT involves addressing several aspects of life that can improve health and weight in collaboration with the family, school and other stakeholders. Healthy foods and nutrition, meal size, meal order, screen time, physical activity and psychological wellbeing are all addressed, often by a multi-disciplinary treatment team.
From 2023, the GLP-1 drugs, initially liraglutide and later semaglutide, were included in some patients' programmes. Around one in four patients were prescribed GLP-1 drugs.
The reduction in average BMI was similar between the cohorts up until 2022.
In the 2023 group, 30% experienced clinically relevant change in BMI – that is, a reduction that was great enough to improve their health (in technical terms, 0.25 standard deviations of BMI). This compares to around 27% of those who were treated earlier.
The researchers attribute this to the addition of the GLP-1 drugs to the treatment programme, although they explain that even in children they are prescribed for, use is not consistent. The design of the study means that different proportions of children are using drugs at different times. One point prevalence estimate from January 2025 showed one quarter of children in the 2023 cohort were using them at that point.
This is not a huge difference yet – but there is a trend, say the researchers. Dr Janson explains: "Only a fraction of the children had GLP-1 drugs and most of those who did started on them 6-12 months into the treatment programme. Longer-term treatment may lead to greater improvements in BMI.
"These are just early indications but it does look as if the average effect of being a patient at our clinic has improved after adding GLP-1 drugs to the toolbox."
Dr Janson concludes: "Many children with severe obesity describe hunger and a strong appetite – both of which GLP-1 receptor agonists are known to help with.
"Results beyond obesity are also important. The families reported reduced conflicts around food and improved capacity for other lifestyle adaptations. It was easier to stick to meals and limit snacks. Portions could be down-sized. For some children, not being hungry all the time is a new feeling.
"GLP-1 receptor agonists are clearly beneficial to many children with severe obesity and while they won't help in all cases, more children should have access to these important medications."
