Cardiovascular risk factor levels and their relationships with overweight and fat distribution in children: the Fleurbaix Laventie Ville Santé II study

Abstract

This study aimed to document for the first time in a general population of French children the prevalence and levels of cardiovascular risk factors and to assess separately in boys and girls whether these risk factors were associated with fat mass distribution independently of subcutaneous overall adiposity. A cross-sectional analysis of baseline data from 452 children (235 boys and 217 girls) aged 8 to 17 years included in a 1999 population-based epidemiologic study (the Fleurbaix Laventie Ville Santé II study) was made. Overweight was defined according to the International Obesity Task Force references and the 90th percentiles of the French body mass index curves. The thresholds of parameters defining cardiovascular and metabolic risks were the 95th percentile of the Task Force Report on High Blood Pressure in Children and Adolescents for blood pressure and those of the American Academy of Pediatrics for lipids. Anthropometric and biological parameters were described by sex and according to overweight status. Partial correlations between cardiovascular risk factors and anthropometric measures of adiposity (body mass index, sum of 4 skinfold thicknesses, waist circumference, waist-to-height ratio) were calculated. Then, these correlations were additionally adjusted for the sum of 4 skinfold thicknesses. High plasma triglycerides, high insulin concentration, and low plasma high-density lipoprotein cholesterol (HDL-C) concentration were associated with all measures of adiposity (|r| > or = 0.20, P < .002). When obese children were excluded, overweight children already had high triglycerides and low HDL-C levels, respectively, 2 and 20 times more frequently than normal-weight children did. Among overweight children, 7.7% had at least 2 risk factors among high blood pressure, high plasma triglycerides or glucose, and low HDL-C concentration vs 0.25% among normal-weight children (P = .002). After adjusting for the sum of skinfolds, an independent association between the risk factors and waist circumference was found in girls. In conclusion, (a) modest excess weight is associated with increased levels of cardiovascular risk factors. (b) In girls, abdominal fat distribution is associated with cardiovascular risk factors, independently of overall adiposity. (c) International definition of abdominal obesity in children is required to standardize studies and to progress in the evaluation of childhood obesity and its consequences.

Figure 1

Pearson’s correlation between cardiovascular risk factors and waist circumference adjusted for age, and Tanner stage, with and without an additional adjustment for the sum of skinfolds (adj. for SSK) in 235 boys and 217 girls (statistical significance: |r|>0.13)