Association of BMI and fasting insulin with cardiovascular disease risk factors in seven-year-old Icelandic children

Abstract

Objective. To look at overweight and common cardiovascular disease (CVD) risk factors, and associations with body mass index (BMI) and fasting insulin in seven-year-old schoolchildren in Reykjavik, Iceland. Study design. Cross-sectional study of seven-year-old schoolchildren. Setting. Six elementary schools in Reykjavik. Subjects. All children attending second grade in these six schools were invited to participate. Main outcome measures. Overweight, fasting serum insulin, CVD risk factors. Results. Some 14% of the participating children were classified as overweight. Overweight children had higher fasting insulin, higher fasting glucose, and higher systolic and diastolic blood pressure. Furthermore, they had significantly lower total cholesterol (TC), lower high-density lipoprotein (HDL), and lower low-density lipoprotein (LDL) but a similar TC/LDL ratio to normal-weight children. The factors that were strongly associated with BMI were serum fasting insulin, systolic blood pressure (SBP), HDL and fasting glucose, while the sum of four skinfolds, triglycerides, glucose, and LDL were highly associated with fasting insulin. Conclusion. Overweight children are likelier to have unfavourable levels of common CVD risk factors included in metabolic syndrome, but surprisingly had lower LDL and TC. Skinfold thickness, higher triglyceride and glucose levels, and being female were associated with increased serum insulin.