Table 1. Demographics of patients (n=64).
| Variables | Groups, n (%) |
P value | |||
|---|---|---|---|---|---|
| Mild, n=36 | Moderate, n=22 | Severe, n=6 | Total, n=64 | ||
| Age, mean ± SD (years) | 19.06±4.28 | 17.81±3.67 | 18.00±4.05 | 18.53±4.04 | 0.505 |
| Male | 31 (86.1) | 15 (68.2) | 5 (83.3) | 51 (79.7) | 0.262 |
| Height, mean ± SD (cm) | 171.36±8.11 | 167.68±10.83 | 173.50±7.97 | 170.30±9.20 | 0.227 |
| Weight, mean ± SD (kg) | 58.31±10.21 | 56.30±12.09 | 53.17±16.47 | 57.14±11.43 | 0.550 |
| BMI, mean ± SD | 19.78±2.58 | 19.79±2.40 | 17.35±4.71 | 19.56±2.81 | 0.130 |
| Smoking | 0.679 | ||||
| Non-smoker | 30 (83.3) | 21 (95.5) | 6 (100.0) | 57 (89.1) | |
| Smoker | 5 (13.9) | 1 (4.5) | 0 (0.0) | 6 (9.4) | |
| Ex-smoker | 1 (2.8) | 0 (0.0) | 0 (0.0) | 1 (1.6) | |
| Season | 0.244 | ||||
| Spring | 11 (30.6) | 2 (9.1) | 2 (33.3) | 15 (23.4) | |
| Summer | 16 (44.4) | 10 (45.5) | 2 (33.3) | 28 (43.8) | |
| Fall | 8 (22.2) | 7 (31.8) | 1 (16.7) | 16 (25.0) | |
| Winter | 1 (2.8) | 3 (13.6) | 1 (16.7) | 5 (7.8) | |
| Predisposing factor | |||||
| Asthma | 2 (5.6) | 2 (9.1) | 0 (0.0) | 4 (6.3) | 0.753 |
| History of pneumothorax | 2 (5.6) | 0 (0.0) | 0 (0.0) | 2 (3.1) | 0.607 |
| Interstitial lung disease | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | N/A |
| Steroid use | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | N/A |
| Subcutaneous emphysema | 13 (36.1) | 9 (40.9) | 5 (83.3) | 27 (42.2) | 0.123 |
Categorical variables are reported as frequencies (%), and continuous variables are reported as mean ± SD. Chi-square test or Fischer’s exact test was used for categorical variables. SD, standard deviation; BMI, body mass index; N/A, not applicable.