Table 2.
Characteristics of male and female participants according to sleep durationa.
| Sleep duration (h/d) | Τrend pb | |||
|---|---|---|---|---|
| <7 | 7-8 | >8 | ||
| Male participants | ||||
| n | 1675 | 3324 | 1252 | |
| BMI (kg/m2) | 23.1 (22.9-23.4)c | 23.2 (23.1-23.4) | 23.3 (23.0-23.5) | 0.381 |
| Grade (%) | ||||
| First year | 30.5 | 30.8 | 30.8 | 0.839 |
| Second year | 28.7 | 29.1 | 28.7 | 0.991 |
| Third year | 26.0 | 24.9 | 25.6 | 0.739 |
| Fourth year | 14.8 | 15.1 | 14.9 | 0.898 |
| Minority race (%) | 5.5 | 6.8 | 6.7 | 0.146 |
| Physical activity (≥23METs h/week; %) | 37.4 | 34.7 | 41.7 | 0.050 |
| Living status (dormitory; %) | 92.5 | 92.2 | 92.8 | 0.791 |
| Smoking status (%) | ||||
| Smoker | 19.3 | 20.1 | 19.5 | 0.865 |
| Drinking status (%) | ||||
| Drinking everyday | 6.6 | 6.3 | 4.2 | 0.012 |
| Drink occasionally | 28.8 | 28.4 | 30.9 | 0.256 |
| Non-drinker | 64.7 | 65.3 | 64.9 | 0.874 |
| Depressive symptom (%) | 18.1 | 19.7 | 19.8 | 0.211 |
| Regular consumption of Hypnotic drug (%) | 1.3 | 1.5 | 0.7 | 0.269 |
| Female participants | ||||
| n | 1032 | 2147 | 695 | |
| BMI (kg/m2) | 21.3 (21.0-21.5) | 21.2 (21.0-21.3) | 21.1 (20.8-21.4) | 0.449 |
| Grade (%) | ||||
| First year | 28.2 | 29.5 | 27.2 | 0.781 |
| Second year | 27.0 | 27.5 | 28.9 | 0.411 |
| Third year | 25.7 | 24.9 | 27.2 | 0.577 |
| Fourth year | 19.1 | 18.1 | 16.7 | 0.207 |
| Minority race (%) | 8.2 | 7.0 | 8.3 | 0.890 |
| Physical activity (≥23METs h/week; %) | 32.1 | 34.9 | 38.7 | 0.005 |
| Living status (dormitory; %) | 92.1 | 90.4 | 91.1 | 0.373 |
| Smoking status (%) | ||||
| Smoker | 2.7 | 1.7 | 2.7 | 0.765 |
| Drinking status (%) | ||||
| Drinking everyday | 5.3 | 4.6 | 3.3 | 0.054 |
| Drink occasionally | 20.7 | 20.7 | 23.5 | 0.225 |
| Non-drinker | 73.9 | 74.7 | 73.2 | 0.832 |
| Depressive symptom (%) | 16.5 | 19.8 | 20.4 | 0.026 |
| Regular consumption of Hypnotic drug (%) | 1.9 | 1.6 | 0.9 | 0.090 |
a
BMI: body mass index; PA: physical activity.
b
Obtained using ANOVA for continuous variables and x2 test for proportional variables.
c
Mean; 95% CI in parentheses (all such values).