A new study shows that children with overweight differ considerably in metabolic profile and possibly also risk of complications. A researcher says that considering each child’s cardiometabolic risk profile is important when treating them.
More and more children worldwide have overweight, but their cardiometabolic risk profiles differ greatly.
A new study recently unveiled at the 2023 European Congress on Obesity concludes that some children with overweight may have greater risk than others of developing cardiovascular disease and diabetes. This should be considered when treating children with overweight and obesity.
The researchers investigated how children with obesity differed in their metabolic responses to an oral glucose tolerance test. Although the children were all the same age and had the same degree of overweight, their hormonal responses to the glucose tolerance test differed greatly and thus possibly also their metabolic risk profile.
“You cannot determine whether a child has an increased risk of developing comorbidities simply based on their degree of overweight or obesity.. Children with overweight are very diverse, and in-depth research is required to elucidate who has increased risk because of their overweight and who appears to be metabolically protected,” explains a researcher behind the study, Emilie Hovendal, Research Assistant, Children’s Obesity Clinic, Holbæk Hospital and Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen.
Close interaction between obesity, metabolites and gut hormones
The researchers previously showed that elevated fasting glucagon among children and adolescents was associated with a higher cardiometabolic risk profile with more insulin resistance, dyslipidaemia and hypertension than children and adolescents with lower fasting levels of glucagon.
Glucagon is a hormone similar to insulin that helps to regulate blood glucose, but whereas insulin lowers the blood glucose, glucagon causes blood glucose to increase. Insulin resistance, dyslipidaemia and hypertension are typically associated with obesity and the development of type 2 diabetes.
The researchers behind the study also previously identified that children and adolescents with high fasting levels of the gut hormone GLP-1 similarly have an increased tendency to have higher levels of insulin resistance, dyslipidaemia and hypertension.
GLP-1 is released in the gut in connection with the intake of food and stimulates the release of insulin and inhibits the release of glucagon. GLP-1 also delays gastric emptying thereby delaying the absorption of glucose from the gut, decreasing postprandial glucose excursions..
“In this new study, we wanted to advance the understanding of the link between these hormones and determine whether children and adolescents with overweight or obesity, with or without insulin resistance, and controls with normal weight differ in fasting and glucose-stimulated levels of insulin, glucagon, GLP-1 and GIP,” says Emilie Hovendal.
Eighty children from Denmark
The researchers recruited 80 children and adolescents from both the Children’s Obesity Clinic of Holbæk Hospital and from schools around Zealand as controls with normal weight.
The participants were 7–17 years old and were divided into three groups:
- children and adolescents with overweight and insulin resistance;
- children and adolescents with overweight and without insulin resistance; and
- children and adolescents without overweight or insulin resistance.
The children fasted for 10 hours, and then the researchers carried out an oral glucose tolerance test in which they gave the children glucose and then took blood samples to see how their body reacted to eliminate the glucose.
Both before the glucose tolerance test and at various times afterwards, the researchers examined the levels of glucose, insulin, glucagon, GLP-1 and GIP.
Insulin resistance increases cardiometabolic risk
The study shows that children with overweight and insulin resistance respond differently to glucose stimulation and may differ in their cardiometabolic risk profile from children with overweight without insulin resistance and children with normal weight.
The children with overweight and insulin resistance had higher blood levels of glucose, insulin, glucagon and GLP-1 before the glucose tolerance test, which indicates a body struggling to maintain glucose balance.
During the test, children with overweight and insulin resistance also experienced a smaller decrease in glucagon and a lower GLP-1 response than the other two groups.
“This indicates that children with overweight have diverse risk profiles and thus their risk of developing cardiovascular disease and type 2 diabetes later in life differs considerably. We should remember this in our approach to children with overweight and obesity, because those with insulin resistance seem to be more at risk in terms of cardiometabolic consequences of their overweight,” explains Emilie Hovendal.
Further studies required
Emilie Hovendal and colleagues are already carrying out several studies involving children and adolescents with overweight and obesity and their cardiometabolic risk profiles.
The researchers are examining how genetics affects the effects of GLP-1 in the body and will reach out to all the children associated with the Children’s Obesity Clinic 10 years later to investigate the long-term effects of having overweight and obesity in childhood.
“For many years, we have tended to look exclusively at body mass index when assessing the degree of illness associated with overweight, but we are moving away from this, because body mass index alone cannot determine the consequences of having overweight for each individual child. However, we need more studies to uncover what appears to increase the risk of cardiometabolic complications among children and adolescents with overweight and obesity and what appears to be protective,” concludes Emilie Hovendal.
