MedWire News: The authors of a systematic review caution that focusing only on children who are overweight or obese for the promotion of healthy weight management may miss an important at-risk group.

"There is a widely held assumption that childhood obesity is an independent risk factor for adult metabolic and cardiovascular disease," write the investigators. However, in the present study they found "insufficient evidence" to support the idea that childhood obesity independently increases the risk for dyslipidaemia and insulin resistance in adulthood.

Conversely, the results demonstrated that individuals who were lean as children seemed to be most susceptible to the metabolic risk associated with adult obesity.

The researchers searched the literature for studies investigating the association between childhood body mass index (BMI) and adult metabolic risk. A total of 11 articles met criteria for inclusion in the present analysis.

Sarah McMullen and team, from the University of Nottingham in the UK, report that several studies identified weak positive associations between childhood BMI and adult total cholesterol, low-density lipoprotein cholesterol, triglycerides, and insulin concentrations. However, they note that the majority of these studies failed to adjust for adult BMI, and therefore "may reflect the tracking of BMI across the lifespan."

Of the studies that did adjust for adult BMI, the data suggest a weak negative association between childhood obesity and metabolic variables, with those at the lower end of the BMI range in childhood, but obese during adulthood, at particular risk.

These findings "could be interpreted as a slight protective effect of obesity in childhood," remark the authors.

Additionally, of the four papers that considered the metabolic syndrome as an end point, none showed evidence of an independent association with childhood obesity.

"We are not suggesting that childhood obesity is without consequences," say McMullen and team.

"Targeting childhood and adolescence for prevention and treatment of obesity is wholly appropriate to establish a healthy weight moving forward into the adult years. However, it is evident from this systematic review that the nature of the relationship between early BMI and adult disease risk is very complex," they conclude.

The findings are published in the International Journal of Obesity.

MedWire (http://www.medwire-news.md/) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012

Free abstract