Table 1.
Demographic and lung function characteristics of the 36 subjects who completed routine Mch challenge testing
| Parameter | Nonobese (n = 19) | Obese (n = 17) |
|---|---|---|
| Age, yr | 31 ± 8 | 42 ± 12‡ |
| # (%) Female | 12 (63) | 11 (65) |
| # (%) Caucasian | 14 (74%) | 9 (53%) |
| # (%) Former smokers | 1 (5) | 0 (0) |
| # (%) Skin test negative | 16 (84) | 12 (71) |
| BMI | 22 ± 2 | 35 ± 5*† |
| FEV1, %pred | 101 ± 8 | 93 ± 10* |
| FVC, %pred | 100 ± 8 | 95 ± 10 |
| FEV1/FVC | 0.84 ± 0.05 | 0.80 ± 0.04*† |
| TLC, %pred | 101 ± 13 | 94 ± 15 |
| RV, %pred | 93 ± 33 | 83 ± 29 |
| RV/TLC | 0.26 ± 0.06 | 0.28 ± 0.08 |
| FRC, %pred | 96 ± 16 | 94 ± 25 |
| ERV, %pred | 99 ± 17 | 70 ± 40† |
| SVC, liter | 4.43 ± 1.05 | 3.73 ± 1.07 |
| IC, liter | 2.71 ± 0.76 | 2.65 ± 0.76 |
| R5 | 2.89 ± 0.57 | 4.31 ± 0.80‡ |
| R20 | 2.88 ± 0.58 | 3.45 ± 0.54‡ |
| R5-R20 | 0.01 ± 0.27 | 0.86 ± 0.52‡ |
| AX | 1.91 ± 0.92 | 7.22 ± 4.21‡ |
| # with PC20 | 2 | 5 |
Data shown as mean±SD unless indicated. Demographic and lung function characteristics of the 30 subjects who underwent both routine and modified methacholine (Mch) challenges were not statistically different from those of the 36 subject cohort. BMI, body mass index; FEV1, forced expiratory value in 1 s; FVC, forced vital capacity; RV, residual volume; FRC, functional residual capacity; SVC, slow vital capacity; IC, inspiratory capacity; R5, R20, resistance at 5 and 20 Hz, respectively.
*
P < 0.05;
†
P < 0.01;
‡
P < 0.005.