Table 2.
Event Rates by Exposure Status
| Crohn Disease | Ulcerative Colitis | Crohn Disease | Ulcerative Colitis | |||||
|---|---|---|---|---|---|---|---|---|
| TNF Inhibitors | Nonbiologics | TNF Inhibitors | Nonbiologics | Infliximab | Adalimumab | Infliximab | Adalimumab | |
| Before matching | ||||||||
| Number of patients | 21,477 | 16,472 | 8597 | 12,925 | 14,855 | 12,904 | 8509 | 3876 |
| Number of person-years | 22,781 | 13,910 | 8034 | 12,151 | 15,756 | 14,550 | 8745 | 3328 |
| Number of events | 25 | 26 | 13 | 18 | 10 | 17 | 4 | 8 |
| Rate per 1000 person-years | 1.1 (0.7, 1.6) | 1.9 (1.2, 2.7) | 1.6 (0.9, 2.8) | 1.5 (0.9, 2.3) | 0.6 (0.3, 1.2) | 1.2 (0.7, 1.9) | 0.5 (0.1, 1.2) | 2.4 (1.0, 4.7) |
| Rate difference per 1000 person-years (vs. referent; 95% CI) | Referent | 0.77 (−0.07, 1.61) | Referent | −0.14 (−1.25, 0.98) | Referent | 0.53 (−0.15, 1.21) | Referent | 1.95 (0.22, 3.67) |
| Hazard ratio (95% CI) | Referent | 1.75 (0.95, 3.22) | Referent | 1.01 (0.43, 2.38) | Referent | 3.18 (1.20, 8.41) | Referent | 1.46 (0.39, 5.51) |
| After propensity score matching | ||||||||
| Number of patients | 14,044 | 14,044 | 7045 | 7045 | 9200 | 9200 | 2984 | 2984 |
| Number of person-years | 15,606 | 11,399 | 6840 | 5965 | 9570 | 10,762 | 2639 | 2708 |
| Number of events | 20 | 18 | 10 | 12 | 6 | 14 | 2 | 5 |
| Rate per 1000 person-years | 1.28 | 1.58 | 1.46 | 2.01 | 0.63 | 1.30 | 0.76 | 1.85 |
| Rate difference per 1000 person-years (vs. referent; 95% CI) | Referent | 0.30 (−0.62, 1.22) | Referent | 0.55 (−0.90, 2.00) | Referent | 0.67 (−0.17, 1.52) | Referent | 1.09 (−0.84, 3.02) |
| Hazard ratio (95% CI) | Referent | 1.22 (0.64, 2.30) | Referent | 1.35 (0.58, 3.12) | Referent | 2.10 (0.81, 5.46) | Referent | 2.45 (0.48, 12.62) |