Prevalence and geographic variation of abdominal obesity in 7-and 9-year-old children in Greece; World Health Organization Childhood Obesity Surveillance Initiative 2010

Background: In children, abdominal obesity is a better predictor of the presence of cardiovascular risk factors than body mass index (BMI)-defined obesity. We aimed to evaluate the prevalence of abdominal obesity in the Greek pediatric population and to assess the impact of residence on the prevalence of both BMI-defined and abdominal obesity. Methods: In the context of the Childhood Obesity Surveillance Initiative of the World Health Organization (WHO) Regional Office for Europe, a national representative sample of 7.0-7.9 and 9.0-9.9-year-old children was evaluated (n = 2,531 and 2,700, respectively). Overweight and obesity according to BMI were estimated using both the WHO and International Obesity Task Force cut-off points. Abdominal obesity was defined as waist circumference/height ratio > 0.5. Results: The prevalence of abdominal obesity did not differ between 7-year-old boys and girls (25.2 and 25.3%, respectively; p = NS). Among 9-year-old children, abdominal obesity was more prevalent in boys than in girls (33.2 and 28.2%, respectively; p = 0.005). Among normal weight and overweight children, the prevalence of abdominal obesity was 1.6- 6.8 and 21.8-49.1%, respectively. The prevalence of abdominal and BMI-defined obesity did not differ between children living in the mainland, in Crete and in other islands except in 7-year-old girls, where the prevalence of BMI-defined obesity was highest in those living in Crete, intermediate in those living in other islands and lowest in those living in the mainland. In 9-year-old boys and in 7- and 9-year-old girls, the prevalence of abdominal obesity was highest in children living in Athens and lowest in children living in Thessaloniki, whereas children living in other cities and in villages showed intermediate rates. The prevalence of abdominal obesity in 7-year-old boys and the prevalence of BMI-defined obesity did not differ between children living in cities and villages. Conclusions: The prevalence of pediatric abdominal obesity in Greece is among the highest worldwide. Boys and children living in the capital are at higher risk for becoming obese. Given that abdominal obesity is more prevalent than BMI-defined obesity and appears to be more sensitive in identifying cardiovascular risk, measurement of waist circumference might have to be incorporated in the screening for childhood obesity.