Table 2.
Significant variables associated with outcomes and predictive models.
| Gene expression univariable analysis | Multivariable predictive models | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| OR | p value | OR | p value | AUC | Sen | Spec | LR+ | LR− | LR test* | ||
| CSFR [week 52] | PROTECT Model | ||||||||||
| IL13RA2 | 0.83 [0.74–0.94] | 0.002 | PUCAI < 45 | 1.87 [1.08–3.24] | 0.024 | 0.72 [0.66–0.79] | 35% [25–45] | 86% [81–91] | 2.56 [1.61–4.06] | 0.76 [0.65–0.88] | NA |
| S100A8 | 0.84 [0.74-0.96] | 0.010 | Hgb ≥ 10 | 3.55 [1.00–12.63] | 0.082 | ||||||
| RORC | 1.49 [0.98-2.28] | 0.065 | Wk4 Rem | 12.01 [3.51–41.14] | <0.001 | ||||||
| PROTECT Model + IL13RA2 | |||||||||||
| PUCAI < 45 | 1.81 [1.04–3.14] | 0.030 | 0.74 [0.68–0.80] | 45% [35–55] | 82% [76–87] | 2.48 [1.69–3.64] | 0.67 [0.56–0.81] | 0.052 | |||
| Hgb ≥ 10 | 3.48 [0.98–12.45] | 0.090 | |||||||||
| Wk4 Rem | 11.19 [3.25–38.50] | <0.001 | |||||||||
| IL13RA2 | 0.89 [0.78–1.00] | 0.046 | |||||||||
| Model without Wk4 data | |||||||||||
| PUCAI < 45 | 2.20 [1.25–3.87] | 0.006 | 0.70 [0.63–0.77] | 33% [23–43] | 89% [83–93] | 2.95 [1.74–5.00] | 0.76 [0.65–0.88] | 0.029 | |||
| Hgb ≥ 10 | 2.28 [1.10–4.74] | 0.026 | |||||||||
| Vit D level | 1.05 [1.01–1.09] | 0.010 | |||||||||
| IL13RA2 | 0.87 [0.76–0.99] | 0.032 | |||||||||
| CSNR [week 12] | |||||||||||
| IL13 | 1.28 [1.06–1.54] | 0.009 | IL13 | 1.28 [1.06–1.54] | 0.009 | 0.68 [0.57–0.79] | 67% [51–80] | 65% [50–79] | 1.92 [1.22–3.01] | 0.51 [0.32–0.82] | NA |
| ALOX15 | 1.38 [0.99–1.92] | 0.059 | |||||||||
| Escalation to IFX [week 52] | |||||||||||
| IL25 | 1.39 [1.06–1.82] | 0.016 | IL33 | 0.66 [0.47–0.93] | 0.017 | 0.66 [0.58–0.74] | 41% [29–53] | 74% [64–83] | 1.58 [1.02–2.47] | 0.80 [0.64–1.00] | NA |
| IL13RA2 | 1.25 [1.04–1.50] | 0.016 | IL13RA2 | 1.28 [1.06-1.54] | 0.010 | ||||||
| IL33 | 0.68 [0.49–0.94] | 0.020 | |||||||||
| ALOX15 | 0.77 [0.61–0.99] | 0.040 | |||||||||
| Colectomy [week 52] | |||||||||||
| RORC | 0.28 [0.10–0.78] | 0.015 | RORC | 0.36 [0.14–0.95] | 0.040 | 0.71 [0.57–0.85] | 22% [6–46] | 92% [86–96] | 2.63 [0.94–7.34] | 0.86 [0.68–1.09] | 0.033 |
| ALOX15 | 0.70 [0.48–1.01] | 0.056 | PUCAI < 45 | 0.14 [0.02–0.97] | 0.050 | ||||||
95% confidence intervals of predictive statistics are presented in parentheses. Probability cutoffs: 0.5 [CSFR, CSNR, Escalation to IFX]; 0.2 [Colectomy].
CSFR, corticosteroid-free remission; CSNR, corticosteroid-naïve remission; IFX, infliximab; OR, odds ratio; PUCAI, Pediatric Ulcerative Colitis Activity Index; Hgb, haemoglobin; Wk4 Rem, week 4 remission; OR, odds ratio; AUC, area under the curve; Sen, sensitivity; Spec, specificity; LR, likelihood-ratio; NA, not applicable.
LR test compares the indicated model to the same model including only clinical variables without rectal mucosal gene expression data.