Table 2.
Pooled odds risks (OR) and 95% confidence intervals (CIs) of irreversible airway obstruction asthma and risk factor in cohort or case control study.
| Type | Number of studies | OR (95% CI) Fixed effects |
OR (95% CI) Random effects |
I 2 |
|---|---|---|---|---|
| Age | 5 (cohort) | 1.037 (1.012, 1.062) | 1.023 (0.878, 1.192) | 92.4% (R) |
| Male | 10 (case control) | 2.222 (1.821, 2.731) | 53.3% (F) | |
| Age at onset | 4 (cohort) | 0.971 (0.937, 1.006) | 1.166 (0.646, 2.103) | 47.2% (R) |
| Disease duration | 5 (cohort) | 1.062 (1.038, 1.086) | 1.158 (1.026, 1.308) | 91.6% (R) |
| Rhinitis | 3 (case control) | 0.31 (0.24, 0.40) | 0.0% (F) | |
| Atopic dermatitis | 2 (cohort) | 0.599 (0.424, 0.848) | 2.1% (F) | |
| Aspirin sensitivity | 2 (cohort) | 2.053 (1.417, 2.689) | 1.826 (0.263, 12.693) | 92.4% (R) |
| Smoking | 9 (case control) | 1.79 (1.46, 2.19) | — | 38.2% (F) |
| Sputum eosinophils | 2 (cohort) | 0.979 (0.937, 1.022) | 2.514 (0.334, 18.893) | 91.6% (R) |
| Blood eosinophils | 2 (cohort) | 2.031 (0.958, 4.304) | 32.4% (F) | |
| FENO | 2 (cohort) | 2.156 (1.050, 4.425) | 0.0% (F) | |
| Atopy | 8 (case control) | 0.584 (0.466, 0.732) | — | 22.2 (F) |
R: randomised effects; F: fixed effects.