Table 1 Characteristics of the sample, by sex
Characteristics | Boys (n = 1272) | Girls (n = 1507) | P value |
|---|---|---|---|
Anthropometrics | |||
Age, (years) | 13.26 (2.19) | 13.17 (2.21) | 0.294 |
Weight, (kg) | 47.55 (12.55) | 46.16 (10.67) | 0.002 |
Height, (cm) | 155.55 (13.87) | 150.64 (9.54) | < 0.001 |
Body mass index, (kg/m2) | 19.33 (2.90) | 20.11 (3.18) | < 0.001 |
Body mass index, (z-score) | 0.39 (0.91) | 0.43 (0.78) | < 0.001 |
Waist circumference, (cm) | 65.69 (7.42) | 63.70 (7.42) | < 0.001 |
Sexual maturity | |||
Prepuberty, n (%) | 85 (6.68) | 78 (5.17) | |
Puberty, n (%) | 650 (51.11) | 734 (48.77) | 0.157 |
Postpuberty, n (%) | 537 (42.21) | 696 (46.18) | |
Blood sampling | |||
HDL-c, (mg/dL) | 46.91 (12.36) | 47.49 (12.23) | 0.215 |
Triglycerides, (mg/dL) | 85.19 (39.07) | 96.53 (54.73) | < 0.001 |
Fasting blood glucose, (mg/dL) | 83.45 (15.82) | 81.52 (15.72) | 0.001 |
Systolic blood pressure, (mmHg) | 113.39 (14.04) | 110.30 (12.36) | < 0.001 |
Diastolic blood pressure, (mmHg) | 68.19 (9.31) | 68.45 (8.59) | 0.443 |
Cardiorespiratory fitness, (ml.kg.min−1) | 50.13 (3.66) | 35.55 (2.79) | < 0.001 |
Sleep duration | |||
Week days, hours/night | 8.11 (1.61) | 8.09 (1.69) | 0.811 |
Weekend, hours/night | 9.63 (1.85) | 9.82 (1.91) | 0.010 |
Short-long durationa | 479 (37.7) | 939 (62.3) | 0.102 |
Sleep patterns | |||
Short sleep duration, n (%) | 900 (70.48) | 1055 (69.78) | 0.686 |
Bedtime problems, n (%) | 292 (22.87) | 374 (24.74) | 0.249 |
Excessive day sleepiness, n (%) | 396 (31.01) | 673 (44.51) | < 0.001 |
Awakenings during the night, n (%) | 248 (19.42) | 320 (21.16) | 0.255 |
Regularity and duration of sleep, n (%) | 407 (31.87) | 611 (40.41) | < 0.001 |
Metabolic syndrome (abnormal values) | |||
High waist circumference, n (%)b | 55 (4.38) | 50 (3.34) | 0.155 |
Low HDL-c levels, n (%) | 833 (65.23) | 978 (64.68) | 0.762 |
High triglycerides levels, n (%) | 278 (21.77) | 497 (32.87) | < 0.001 |
High fasting blood glucose, n (%) | 67 (5.25) | 68 (4.50) | 0.358 |
High systolic blood pressure, n (%)c | 201 (16.22) | 196 (13.17) | 0.025 |
High diastolic blood pressure, n (%)c | 130 (10.49) | 165 (11.09) | 0.618 |
Components metabolic syndrome, n (%)d | |||
0 | 280 (22.16) | 317 (21.03) | 0.017 |
1 | 571 (44.87) | 615 (40.94) | |
2 | 308 (24.12) | 419 (27.71) | |
3 | 82 (6.42) | 132 (8.73) | |
4 | 26 (2.04) | 19 (1.26) | |
5 | 5 (0.39) | 5 (0.33) | |