ABSTRACT
OBJECTIVES: To determine the best anthropometric index in relation to cardiovascular disease risk factors among children and adolescents. METHODS: This cross-sectional school-based study was conducted among a random sample of 3179 students, aged 6 to 18 years, in three large cities in Brazil. RESULTS: The prevalence of overweight and obesity was 10% and 5%, respectively. In relation to the students in the lower quartile (Q1) of the distribution of subscapular skinfold, the students in the upper quartile (Q4) presented a 2.0 times higher risk (odds ratio) of having elevated total cholesterol levels. Overweight and obese students had a 3.3 times higher risk of having elevated systolic blood pressure, and a 1.9 times higher risk of elevated diastolic blood pressure than other students. The less active students presented a 1.58 times higher risk of having waist-to-height ratio (WHtR) above the upper tertile (Q3). WHtR mean values was 0.46 (SE 0.00) presented the largest area under the curve (AUC) [0.613 (CI995%:0.578-0.647)] for high total cholesterol levels, [0.546 (CI995%: 0.515-0.578)] for low HDL-C levels, and [0.614 (CI95%: 0.577-0.651)] for high LDL-C levels, while body mass index presented the largest AUC [0.669 (CI95%: 0.64-0.699)] for increased diastolic blood pressure followed by the waist circumference for increased systolic blood pressure [0.761 (CI95%: 0.735-0.787)]. CONCLUSIONS: WHtR is considered as a simple and accurate anthropometric parameter that identifies youth with cardiovascular risk factors. In this study, WHtR above 0.44 was indicative of risk factors in children and adolescents. These findings can be applied in future preventive strategies against CVDs, and screening programs.
ABSTRACT
OBJECTIVE: To verify an association, if it exists, between obesity and blood pressure raised beyond the 90th percentile in children and adolescents, and to determine the measure of adiposity that best correlates with blood pressure in these subjects. DESIGN: Cross-sectional study. SETTING: A school-based study in Belo Horizonte, Brazil. PARTICIPANTS: We selected randomly 1,403 students, aged from 6 to 18 years, from 545,046 students attending 521 public and private schools. Those selected completed the study. MAIN MEASURES OF OUTCOME: We recorded the weight, height, skin fold in the triceps, subscapular, and suprailiac areas, waist and hip circumference, body-mass index, and resting systolic and diastolic blood pressures using a mercury sphygmomanometer. RESULTS: In univariate analyses, body mass index greater or lesser than 85th percentile, measurements of skin thickness in the subscapular and suprailiac areas, and the sum of all measurements of skinfold thickness, were associated with both systolic and diastolic measurements of blood pressure. After multivariate analyses that adjusted for all measurements of adiposity except itself, and age, race, and socioeconomic state, we found that the increased body mass index was associated with a 3.6-fold increased frequency of elevated systolic measurements of blood pressure, with 95% confidence intervals from 2.2 to 5.8, and a 2.7-fold increased frequency of elevated measurements of diastolic blood pressure, with 95% confidence intervals from 1.9 to 4.0. CONCLUSIONS: Body-mass index serves as a better predictor of elevated blood pressure among children than do local measurements of adiposity.
