Sociodemographic characteristics according to asthma status at baseline, Nurses’ Health Study II
| Asthma history before 1989 | |||
|---|---|---|---|
| No | Yes | p Value | |
| N | 92 737 | 5311 | |
| Age, mean (SD) | 34.3 (4.7) | 35.0 (4.6) | <0.001 |
| Age group | |||
| 24–30 | 18.4 | 14.0 | <0.001 |
| 30–35 | 31.9 | 30.6 | |
| 35–40 | 32.5 | 35.7 | |
| 40–44 | 17.2 | 19.8 | |
| Race/ethnicity | |||
| Non-white, % | 7.1 | 7.0 | 0.73 |
| Hispanic, % | 1.8 | 2.1 | 0.16 |
| Smoking habits, % | |||
| Never-smoker | 65.0 | 64.1 | <0.001 |
| Ex-smoker | 21.1 | 24.5 | |
| Current smoker | 13.8 | 11.3 | |
| Missing | 0.1 | 0.1 | |
| BMI (kg/m2), % | |||
| <25 | 69.5 | 60.7 | <0.001 |
| 25–29.9 | 18.6 | 21.0 | |
| ≥30 | 11.3 | 17.6 | |
| Missing | 0.6 | 0.7 | |
BMI, body mass index.