ABC | Volume 110, Nº3, March 2018

Original Article Scherr et al Cardiovascular risk in teenager athletes Arq Bras Cardiol. 2018; 110(3):248-255 The aim of the present study was to evaluate and compare cardiovascular risk factors between adolescent students enrolled in an EOG and students of a public school in which the sports program was not performed. Methods Observational, cross-sectional study conducted with students enrolled in two Rio de Janeiro City public schools. The EOG was located at the district of Santa Teresa. The students were selected for their sports potential to participate in a special training program of different sports, 10 hours weekly, and had five meals a day. The program was started one year before the study. At Fernando Pimentel (FP) School, the students participated in usual physical education activities, one hour per week, and had one meal a day at school. Students at the sixth to ninth grade of elementary school of both schools were recruited. Students who had the informed consent form signed by their parents or guardians, and who met the criterion of a 12-hour fast before blood collection, were included in the study. The students underwent an interview, physical examination and capillary blood sampling by trained professionals. Blood pressure was measured (in mmHg) with the children comfortably seated, on the right arm, using a calibrated aneroid sphygmomanometer (Welch Allyn Tycos, modelo DS 58-MC). Waist circumference was measured using a measuring tape the midpoint between the iliac crest and the lowest rib. The Accutrend Plus System kit (Roche Diagnostics) was used for determination of glucose, total cholesterol (TC) and triglycerides (TG) levels in the samples of capillary blood. Echocardiography was performed using a Vscan portable ultrasound model 1.0 (GE Healthcare, series number (VH01688751) by a trained technician and all reports were written by a qualified physician. The test results were recorded on the data collection form immediately after the tests were performed. Each sport was individually analyzed and classified into two categories according to their respective metabolic equivalent of task (MET) (2011 Compendium of Physical Activities) – MET < 5.0/low (table tennis, chess) and MET ≥ 5.0/high (swimming, soccer, judo, athletics, handball and volleyball). 9 Students who practiced at least one sport with MET ≥ 5.0 were included in the second group. Blood pressure (BP) measurements were categorized according to the percentile of systolic and/or diastolic blood pressure into normal (< 90 th  percentile), prehypertension (90 th  – 95 th  percentile) and hypertension (≥95 th percentile). 10 Capillary blood glucose, and TC and TG levels were classified based on previously published guidelines. 7,11 Statistical analysis Statistical analysis was performed using the Stata software version 12. The Kolmogorov-Smirnov test was used to determine the distribution of continuous variables. Since all continuous variables had a normal distribution, data were expressed by descriptive analysis as mean and standard deviation (SD), and the unpaired t-test was used for comparisons. Categorical variables were expressed as proportion, and the chi-square test used for comparison. Logistic regression was used to assess the association between altered outcomes and exposure variables, with control of all possible confounding variables. Level of significance was set at p < 0.05. Results A total of 148 students enrolled at FP School and 274 enrolled at the EOGwere included in the study. Students’ mean age was not different between the schools – 12.5 years at FP School and 12.6 years at the EOG. At FP School and EOG, 65.5% and 43.3% of the students, respectively, were female (p<0.01). Sports practiced at the EOG are described in Table 1. Only 20% of the students participated only in sports classified as MET < 5.0 (table tennis or chess). At FP School, 73.4% of the students did not practice sports regularly outside the school. Mean weight and body mass index (BMI) were 52.3% kg and 21.2 kg/m 2 of the students of the FP School and 52.4% kg and 20.7 kg/m 2 of the students of the EOG (p = 0.28). Mean TC level was 164.3 mg/dL and 158.3 mg/dL at FP School and EOG, respectively, whereas median TGwas 89 mg/dL in both schools (interquartile ranges, IQRs: 73-121 mg/dL at FP School and 65-114 mg/dL at the EOG). Mean BP was 110 x 66 mmHg at FP School and 101 x 65 mmHg at the EOG. Table 2 describes metabolic characteristics of the students. Significant differences were found between the students enrolled at FP School and the EOG in the frequency of SAH (20% vs . 6.3%; p < 0.01) and borderline high‑cholesterol (27.7% vs . 17.3%, p = 0.01). Students from the FP School had a 4.3 times higher chance to develop SAH (odds ratio, OR 4.4; 95% CI 2.1 – 8.6; p < 0.01) and a 1.7 times higher chance to have borderline high TC (OR 1.7; 95% CI 1.05 – 2.8; p = 0.03) than students from the EOG, when both age and sex were considered. Capillary glucose levels were at desirable levels (< 101 mg/dL) in all students from both schools, but 40% of them were overweight or obese. Besides, nearly 50% of the students had TG levels above desirable levels. No difference was found in nutritional status or altered TG between the groups (Table 2). Considering the subgroups of EOG students divided by the sports they practiced and respective METs, no differences were found in age or sex between the subgroups. Mean weight in the low MET group was 48.5 ± 13 kg, and 53.3 ± 13.1 kg (p = 0.02); this difference may be ascribed to higher lean mass in the latter. No difference was found in BMI and TC, and the median TGwas 89.5mg/dL in both groups (IQRs: 65‑134mg/dL in lowMET and 65-151mg/dL in the highMET group). Borderline high TC was higher in low MET group than in high MET group (26.8% vs . 14.9%; p = 0.04) (Table 3). Considering age and sex, the low MET group had a two times higher chance to have borderline high TC (95% CI 0.98-0.41; p = 0.056). Echocardiographic findings were not different between the FP School and the EOG students. Among the EOG students, hypertensive heart disease, interventricular communication and two cases of mitral valve prolapse were identified, whereas in the FP School group, two cases of interventricular communication were detected. 249