Appendicectomy rates in Crohn’s disease patients and matched controls
| Subject characteristics | Cases (n=335) | Controls (n=941) | Crude OR | 95% CI | p Value | Multivariate analysis OR | 95% CI |
|---|---|---|---|---|---|---|---|
| Mean (SEM) age (y) | 30.3 (0.79) | 31.1 (0.39) | 0.33 | ||||
| Sex | |||||||
| Female | 67.2% | 66% | 0.70 | ||||
| Male | 32.8% | 34% | |||||
| Smoking | |||||||
| Never smoker | 41.2% | 54.2% | 1.00 | (referent) | 1.00 | (referent) | |
| Ex-smoker | 11.6% | 14.2% | 1.08 | 0.72–1.61 | 1.10 | 0.72–1.67 | |
| Current smoker | 47.2% | 31.6% | 1.97 | 1.50–2.57 | <0.0001 | 1.98 | 1.50–2.62 |
| Appendicectomy | (n=335) | (n=835) | |||||
| No | 89.3% | 75.1% | 1.00 | (referent) | 1.00 | (referent) | |
| Yes | 10.7% | 24.9% | 0.36 | 0.25–0.53 | <0.0001 | 0.35 | 0.24–0.52 |
| Age at appendicectomy | (n=335) | (n=830) | |||||
| None | 89.3 | 75.3% | 1.00 | (referent) | 1.00 | (referent) | |
| ≤20 y | 6.5% | 16.5% | 0.34 | 0.21–0.54 | 0.33 | 0.21–0.53 | |
| >20 y | 4.2% | 8.2% | 0.43 | 0.24–0.78 | <0.0001 | 0.41 | 0.22–0.75 |