Table 3. The overall pooled HR on the effect of DM on CRC Prognosis.
| Number of study | Model for meta-analysis | HR (95%CI) | I2 (%) | P for heterogeneity | P for Begger’s test | P for Egger’s test | |
|---|---|---|---|---|---|---|---|
| Colorectal cancer | |||||||
| OS | 23[6–10, 13–20, 27, 29, 30, 33, 36–39, 42, 43] | R | 1.18(1.12, 1.24) | 64.8 | <0.001 | 0.492 | 0.740 |
| CVDS | 3[13, 15, 30] | F | 1.40(1.29, 1.52) | 31.6 | 0.232 | 0.296 | 0.193 |
| CSS | 8[6–8, 13, 15, 29, 30, 39] | R | 1.03(0.93, 1.12) | 63.3 | 0.008 | 0.711 | 0.225 |
| DFS | 4[8, 9, 20, 38] | R | 1.14(0.71, 1.58) | 80.0 | 0.002 | 0.734 | 0.893 |
| RFS | 2[8, 36] | F | 1.08(0.84, 1.23) | 0.0 | 0.771 | — | — |
| Colon cancer | |||||||
| OS | 18[6, 8, 10–13, 28, 31, 32, 34, 35, 40, 41, 44–47] | R | 1.19(1.10, 1.27) | 86.9 | <0.001 | 0.049 | 0.115 |
| CVDS | 1[13] | — | 1.35(1.26, 1.45) | — | — | — | — |
| CSS | 6[6, 8, 12, 13, 28, 35] | F | 1.07(0.98, 1.16) | 38.9 | 0.146 | 0.260 | 0.012 |
| DFS | 2[8, 46] | F | 1.35(1.12, 1.58) | 0 | 0.447 | — | — |
| RFS | 2[8, 46] | F | 1.24(1.04, 1.44) | 0 | 0.634 | — | — |
| Rectal cancer | |||||||
| OS | 10[6, 8, 10, 11, 13, 28, 40, 44, 45] | R | 1.16(1.04, 1.29) | 61.9 | 0.005 | 0.474 | 0.529 |
| CVDS | 1[13] | — | 1.48(1.04, 1.29) | — | — | — | — |
| CSS | 4[6, 8, 13, 28] | R | 1.12(0.91, 1.32) | 55.2 | 0.082 | 0.308 | 0.389 |
| DFS | 1[8] | — | 0.98(0.76, 1.25) | — | — | — | — |
| RFS | 1[8] | — | 0.96(0.72, 1.28) | — | — | — | — |
R: the random effects model; F: the fixed effects model; DM: diabetes mellitus; OS: overall survival; CSS: cancer-specific survival; CVDS: cardiovascular disease—specific survival; DFS: disease-free survival; RFS: recurrence-free survival.