Table 1. Characteristics of all non-smoking females in Wuhan and Zhuhai (N = 1,694).
| Characteristics | Total | Wuhan | Zhuhai | p value |
|---|---|---|---|---|
| N (%) | 1,694 | 1,177 | 517 | — |
| Age, year (Mean ± SD) | 56.0 ± 12.0 | 55.4 ± 12.5 | 57.2 ± 10.6 | 0.003 |
| Height, cm (Mean ± SD) | 153.7 ± 5.7 | 153.8 ± 5.8 | 153.4 ± 5.7 | 0.55 |
| Body mass index, kg/m2, (Mean ± SD) | 24.8 ± 3.6 | 24.8 ± 3.7 | 24.6 ± 3.4 | 0.87 |
| Passive smoking, N (%) | <0.001 | |||
| No | 957 (56.5) | 617 (52.4) | 340 (65.8) | — |
| Yes | 737 (43.5) | 560 (47.6) | 177 (34.2) | — |
| Cooking, N (%) | 0.10 | |||
| No | 246 (14.5) | 182 (15.5) | 64 (12.4) | — |
| Yes | 1448 (85.5) | 995 (84.5) | 453 (87.6) | — |
| Asthma, N (%) | 0.61 | |||
| No | 1689 (99.7) | 1173 (99.7) | 516 (99.8) | — |
| Yes | 5 (0.3) | 4 (0.3) | 1 (0.2) | — |
| Heart disease*, N (%) | 0.003 | |||
| No | 1658 (97.9) | 1160 (98.6) | 498 (96.3) | — |
| Yes | 36 (2.1) | 17 (1.4) | 19 (3.7) | — |
| Physical activity, N (%) | <0.001 | |||
| No | 725 (42.8) | 566 (48.1) | 159 (30.8) | — |
| Yes | 969 (57.2) | 611 (51.9) | 358 (69.2) | — |
| FVC, ml (Mean ± SD) | 2369.9 ± 530.5 | 2436.2 ± 545.2 | 2219.0 ± 461.4 | <0.001 |
| FEV1, ml (Mean ± SD) | 2006.1 ± 462.1 | 2026.1 ± 471.3 | 1960.7 ± 437.5 | 0.007 |
| %FEV1/FVC | 84.8 ± 8.6 | 83.3 ± 8.6 | 88.2 ± 7.5 | <0.001 |
Abbreviations: FVC, forced vital capacity; FEV1, forced expiratory volume in 1 second; SD, standard deviation.
*The 10th version of the International Classification of Diseases (ICD-10) was used to classify heart diseases (ICD-10 codes: I00–I09, I11, I13, and I20–I51).