Children's belly fat? Too much increases heart risk at 10 years old

Children's belly fat? If it's too much, the heart is at risk of disease by age 10. A Danish study finds a strong association between adverse trends in the waist-to-height ratio (an indicator of abdominal obesity) during childhood and an increase in cardiometabolic and cardiovascular risk at age 10. In detail, the new research presented at the European Congress on Obesity (Eco) underway until Wednesday 14 May in Malaga, Spain, highlights that children with abdominal obesity gradually increasing from birth are more likely to show early signs of heart risk, including high blood pressure and higher levels of biomarkers linked to systemic inflammation and metabolic dysfunction, such as triglycerides, insulin resistance, GlycA and high-sensitivity C-reactive protein.

"With childhood obesity rates rapidly increasing worldwide, it is important to understand how so-called 'central obesity'" or abdominal "in childhood is already linked to early signs of metabolic deterioration: elevated blood pressure and circulating biomarkers associated with future cardiometabolic disease," says lead author David Horner, of the University of Copenhagen. Being obese in childhood and adolescence has been associated with cardiovascular, metabolic, neurological, musculoskeletal diseases and premature death in adulthood. In this context, experts highlight, early diagnosis of overweight in children becomes important to allow interventions that can prevent long-term health consequences.

Accumulation of deep abdominal fat is known to be a stronger risk factor for cardiovascular and metabolic diseases than body mass index (BMI) alone. Waist-to-height ratio (waist circumference divided by height) is a central obesity marker and a key predictor of cardiometabolic health, the researchers add. To explore the issue in childhood, the study authors analyzed data from 700 children enrolled in the Copenhagen Prospective Studies on Asthma in Childhood, a population-based longitudinal mother-child cohort study. The children were followed during 14 regular clinic visits from 1 week of life until age 10 years. The child's cardiometabolic risk was derived from composite scores (adjusted for age and sex) of HDL cholesterol (the so-called 'good cholesterol'), triglycerides (fats in the blood), glucose, blood pressure (adjusted for height) and Homa-Ir (insulin resistance).

The researchers identified three waist-to-height ratio trajectories from 1 week to 10 years: a "stable" reference group, comprising two-thirds of the children; a "growing then stabilizing" group, comprising about 1 in 6 children; and a "slowly growing" group, also comprising about 1 in 6 children. After adjusting for potential confounders, the researchers found that children in the "slowly growing" group had cardiometabolic risk scores that were 0.79 standard deviations higher and cardiovascular disease risk scores that were 0.53 standard deviations higher than those in the reference group. These changes represent a "significant departure" from the risk level of the reference population, the experts explain, and indicate a substantial deterioration in cardiometabolic health by age 10.

The group also had higher systolic blood pressure, and higher levels of C-peptide (suggesting the body is producing too much insulin), Homa-Ir (a marker of insulin resistance associated with type 2 diabetes and other metabolic disorders), GlycA and high-sensitivity C-reactive protein, both markers of chronic inflammation linked to cardiovascular disease. Children in the rise-and-stabilize group also had lower levels of the good HDL cholesterol, suggesting a broader set of warning signs of future heart and metabolic disease. Compared to the reference group, the rise-and-stabilize group had significantly lower levels of glycated hemoglobin, suggesting better blood sugar control, and slightly higher levels of apolipoprotein B (ApoB), an independent risk factor for cardiovascular disease.

When researchers looked at the amount of abdominal fat the children had at age 10, they found that it explained most of the differences in health risk between the groups. "This means that children's current level of abdominal fat, not just how it developed over time, was the strongest predictor of their cardiac and metabolic health," Horner said. "Where a child ends up, the amount of abdominal fat they have at age 10, is more important than how they got there. Our findings highlight that a high waist-to-height ratio at age 10 is a key clinical indicator of cardiometabolic risk in children. And this reinforces the importance of monitoring abdominal obesity in routine care, not just by monitoring weight, but specifically abdominal obesity measurements as part of standard assessments."