TABLE 1.
Patient characteristics at baseline
| Characteristics | [ALL] | Derivation | Validation | p‐value | N |
|---|---|---|---|---|---|
| N = 86 | N = 58 | N = 28 | |||
| Age at CD diagnosis | 21.3 [16.8; 28.0] | 20.6 [15.9; 26.3] | 24.5 [17.9; 37.1] | 0.07 | 85 |
| Age at baseline | 36.7 [26.5; 56.1] | 35.0 [24.4; 48.5] | 47.2 [31.6; 61.7] | 0.04 | 86 |
| Gender | 0.70 | 86 | |||
| Female | 42 (48.8%) | 27 (46.6%) | 15 (53.6%) | ||
| Race | 0.55 | 86 | |||
| Black or African American | 2 (2.33%) | 1 (1.72%) | 1 (3.57%) | ||
| White | 84 (97.7%) | 57 (98.3%) | 27 (96.4%) | ||
| Smoking | 0.81 | 86 | |||
| Never | 52 (60.5%) | 36 (62.1%) | 16 (57.1%) | ||
| Active | 13 (15.1%) | 9 (15.5%) | 4 (14.3%) | ||
| Past | 21 (24.4%) | 13 (22.4%) | 8 (28.6%) | ||
| BMI (kg/m2) | 25.5 [21.9; 27.9] | 24.9 [20.8; 27.9] | 25.9 [22.9; 27.9] | 0.54 | 86 |
| Family history of IBD | 0.50 | 86 | |||
| Yes | 32 (37.2%) | 22 (37.9%) | 10 (35.7%) | ||
| Unknown | 3 (3.49%) | 1 (1.72%) | 2 (7.14%) | ||
| Time since diagnosis (months) | 154 [65.5; 327] | 155 [69.0; 297] | 144 [68.3; 344] | 0.84 | 85 |
| Time from diagnosis of stricture to baseline MRE (months) | 6.31 [0.00; 35.7] | 14.4 [0.00; 36.9] | 1.40 [0.00; 34.8] | 0.34 | 86 |
| Disease location (non‐exclusive) | |||||
| Esophagus | 2 (2.33%) | 2 (3.45%) | 0 (0.00%) | >0.99 | 86 |
| Stomach | 3 (3.49%) | 1 (1.72%) | 2 (7.14%) | 0.25 | 86 |
| Duodenum | 8 (9.30%) | 5 (8.62%) | 3 (10.7%) | 0.71 | 86 |
| Jejunum | 7 (8.14%) | 6 (10.3%) | 1 (3.57%) | 0.42 | 86 |
| Ileum | 85 (98.8%) | 57 (98.3%) | 28 (100%) | >0.99 | 86 |
| Colon | 41 (47.7%) | 29 (50.0%) | 12 (42.9%) | 0.69 | 86 |
| Montreal classification: | 0.96 | 84 | |||
| B2 | 34 (40.5%) | 22 (38.6%) | 12 (44.4%) | ||
| B2p | 23 (27.4%) | 16 (28.1%) | 7 (25.9%) | ||
| B3 | 18 (21.4%) | 13 (22.8%) | 5 (18.5%) | ||
| B3p | 9 (10.7%) | 6 (10.5%) | 3 (11.1%) | ||
| Prior ileal resection | 52 (60.5%) | 32 (55.2%) | 20 (71.4%) | 0.23 | 86 |
| Number of prior resections | 1.50 [1.00; 2.00] | 2.00 [1.00; 2.00] | 1.00 [1.00; 2.00] | 0.53 | 52 |
| Anastomotic stricture | 50 (58.1%) | 32 (55.2%) | 18 (64.3%) | 0.57 | 86 |
| Presence of sinus at baseline | 6 (6.98%) | 3 (5.17%) | 3 (10.7%) | 0.39 | 86 |
| Prior EBD of current stricture | 15 (17.4%) | 13 (22.4%) | 2 (7.14%) | 0.13 | 86 |
| Time from last EBD to baseline (months) | 9.17 [6.49; 35.2] | 9.17 [5.55; 36.3] | 20.7 [14.1; 27.4] | >0.99 | 15 |
| Duration of obstructive symptoms (months) | 10.6 [3.45; 21.9] | 12.6 [3.30; 23.8] | 6.59 [5.36; 15.9] | 0.61 | 41 |
| Medications at baseline | |||||
| Five‐Aminosalicylic acid | 19 (22.1%) | 13 (22.4%) | 6 (21.4%) | >0.99 | 86 |
| Systemic corticosteroids | 21 (24.4%) | 14 (24.1%) | 7 (25.0%) | >0.99 | 86 |
| Anti‐metabolites | 9 (10.5%) | 8 (13.8%) | 1 (3.57%) | 0.26 | 86 |
| Methotrexate | 3 (3.49%) | 2 (3.45%) | 1 (3.57%) | >0.99 | 86 |
| Biologics | 51 (59.3%) | 35 (60.3%) | 16 (57.1%) | 0.96 | 86 |
| Albumin g/dl | 4.20 [3.90; 4.50] | 4.20 [3.90; 4.50] | 4.20 [3.88; 4.50] | 0.79 | 69 |
| Hemoglobin g/dl | 13.1 [11.7; 14.1] | 13.1 [11.4; 14.1] | 13.1 [12.0; 14.1] | 0.69 | 74 |
| Fecal calprotectin (mg/kg) | 318 [187; 374] | 309 [201; 395] | 318 [200; 322] | 0.61 | 9 |
| C‐reactive protein (mg/dl) | 0.45 [0.20; 0.92] | 0.45 [0.20; 1.18] | 0.40 [0.15; 0.65] | 0.63 | 28 |
Note: Bold values denote statistical significance at the p < 0.05 level.
Abbreviations: BMI, body mass index; CD, Crohn's disease; EBD, endoscopic balloon dilation; IBD, inflammatory bowel disease; MRE, magnetic resonance enterography.