Table 1. Clinical characteristics of patients with Crohn's disease and ulcerative colitis.
| Patients characteristics | Crohn’s disease | ulcerative colitis | ||
|---|---|---|---|---|
| n | % | n | % | |
| Total | 436 | - | 367 | - |
| Family history of IBD (yes/no*) | 37/348 | 9.6/90.4 | 16/231 | 6.5/93.5 |
| Sex (male/female) | 225/211 | 51.6/48.4 | 162/205 | 44.1/55.9 |
| Smoking habits | - | - | - | - |
| Never | 189 | 46.2 | 222 | 63.8 |
| Former | 108 | 26.4 | 91 | 26.2 |
| Current | 112 | 27.4 | 35 | 10.1 |
| Age at diagnosis | - | - | - | - |
| A1 (<17 years) | 56 | 12.8 | 14 | 3.8 |
| A2 (17–40 years) | 306 | 70.2 | 215 | 58.6 |
| A3 (>40) | 74 | 17.0 | 138 | 37.6 |
| Location | 436 | - | na | - |
| L1* (ileal) | 195 | 44.8 | na | - |
| L2 (colonic) | 60 | 13.8 | na | - |
| L3 (ilealcolonic) | 180 | 41.4 | na | - |
| L4 (L14+L24+L34)** (involvement of the upper digestive tract) | 47 | (10.8) | na | - |
| Location | na | - | 364 | - |
| E1* (proctitis + rectosigmoid) | na | - | 134 | 36.8 |
| E2 (distal) | na | - | 101 | 27.8 |
| E3 (pancolitis) | na | - | 129 | 35.4 |
| Behaviour | 431 | - | na | - |
| B1* (nonstricturing, nonpenetrating) | 187 | 43.4 | na | - |
| B2 (stricturing) | 90 | 20.9 | na | - |
| B3 (penetrating) | 154 | 35.7 | na | - |
| P (B1P+B2P+B3P)** (perianal disease) | 41 | (9.5) | na | - |
| Rectal involvement (yes/no*) | 99/337 | 22.7/77.3 | 228/8 | 96.6/3.4 |
| Colonic involvement (yes/no*) | 229/207 | 52.5/47.5 | 198/38 | 83.9/16.1 |
| Abdominal surgery (yes/no*) | 226/208 | 52.1/47.9 | 23/342 | 6.3/93.7 |
| Extraintestinal manifestations (yes/no*) | 53/383 | 12.2/87.8 | 7/230 | 3.0/97.0 |
| Previous ongoing corticosteroids (yes/no*) | 398/36 | 91.7/8.3 | 225/141 | 61.5/38.5 |
| Steroid dependency (yes/no*) | 189/243 | 43.8/56.3 | 81/206 | 28.2/71.8 |
| Steroid resistance (yes/no*) | 11/422 | 2.5/97.5 | 26/261 | 9.1/90.9 |
| Need for immunosuppressant (yes/no*) | 359/50 | 87.8/12.2 | 130/236 | 35.5/64.5 |
| Response to immunosuppressant (yes*/no) | 229/138 | 62.4/37.6 | 72/51 | 58.5/41.5 |
| Response to biologics (yes*/no) | 198/42 | 82.5/17.5 | 50/19 | 72.5/27.5 |
* Represents the reference in the case-case association studies;
** For L4 and P phenotypes the reference is absence of phenotype;
na: not applicable