Table 4.
Sub-group analyses: Histologic remission vs. persistent histologic activity and risk of clinical relapse in patients with ulcerative colitis in clinical remission and endoscopic healing
| Groups | Categories | No. of studies | Relative risk of relapse (95% CI) | Heterogeneity within groups (I2) | Pinteraction |
|---|---|---|---|---|---|
| Publication type | Full text | 17 | 0.40 (0.30–0.53) |
63 | 0.78 |
| Abstract | 3 | 0.36 (0.21–0.64) |
52 | ||
| Study design | Prospective | 12 | 0.40 (0.28–0.57) |
63 | 0.71 |
| Retrospective | 8 | 0.36 (0.23–0.56) |
65 | ||
| Study location | Western | 13 | 0.48 (0.37–0.63) |
57 | 0.02 |
| Asia | 7 | 0.29 (0.21–0.40) |
0 | ||
| Medication* | 5-ASA only | 5 | 0.37 (0.20–0.70) |
71 | 0.88 |
| Others | 13 | 0.40 (0.28–0.55) |
62 | ||
| Endoscopic reading | Central | 2 | 0.51 (0.14–1.90) |
74 | 0.69 |
| Local | 18 | 0.39 (0.30–0.50) |
63 | ||
| Histological disease activity index | Standardized | 15 | 0.33 (0.23–0.46) |
65 | 0.01 |
| Nonstandardized | 5 | 0.60 (0.45–0.82) |
30 | ||
| Follow-up period | 12 months | 14 | 0.48 (0.38–0.62) |
56 | 0.002 |
| > 12 months | 6 | 0.22 (0.15–0.34) |
0 | ||
| Risk of bias in outcome measurement | Low | 1 | 0.14 (0.04–0.55) |
0 | 0.28 |
| Moderate | 9 | 0.44 (0.31–0.61) |
68 | ||
| High | 10 | 0.39 (0.27–0.55) |
38 |
*
Type of medication used to induce and maintain initial clinical remission; data extraction was not available in two studies.
CI: Confidence intervals