Table 2.
Univariate and multivariate Cox regression analysis of factors associated with cause-specific survival
| Variables (n = 22,079) | Log Rank test | Univariate analysis | Multivariate analysis | ||||
|---|---|---|---|---|---|---|---|
| Mean survival time (95% CI) | χ2 | P value | HR (95% CI) | P value | HR (95% CI) | P value | |
| Sex | 15.655 | < 0.001 | < 0.001 | < 0.001 | |||
| Female | 190.5 (187.8–193.3) | Reference | Reference | ||||
| Male | 184.0 (181.8–186.2) | 1.120 (1.059–1.184) | < 0.001 | 1.198 (1.132–1.267) | < 0.001 | ||
| Age (y) | 137.779 | < 0.001 | < 0.001 | < 0.001 | |||
| 20–39 | 195.5 (188.9–202.2) | Reference | Reference | ||||
| 40–59 | 196.0 (193.7–198.3) | 0.962 (0.850–1.088) | 0.535 | 1.060 (0.936–1.200) | 0.361 | ||
| 60–79 | 174.0 (171.3–176.7) | 1.368 (1.210–1.547) | < 0.001 | 1.575 (1.389–1.784) | < 0.001 | ||
| Year of diagnosis | 186.065 | < 0.001 | < 0.001 | < 0.001 | |||
| 2000–2005 | 171.2 (167.7–174.6) | Reference | Reference | ||||
| 2006–2010 | 140.5 (138.5–142.5) | 0.846 (0.789–0.907) | < 0.001 | 0.815 (0.758–0.876) | < 0.001 | ||
| 2011–2015 | 106.6 (105.6–107.7) | 0.712 (0.662–0.764) | < 0.001 | 0.642 (0.594–0.693) | < 0.001 | ||
| 2016–2021 | 64.7 (64.2–65.1) | 0.563 (0.512–0.619) | < 0.001 | 0.505 (0.456–0.558) | < 0.001 | ||
| Race | 0.554 | 0.457 | < 0.001 | < 0.001 | |||
| White | 187.5 (185.6–189.4) | Reference | Reference | ||||
| Black | 167.5 (161.2–173.8) | 1.390 (1.271–1.521) | < 0.001 | 1.354 (1.237–1.482) | < 0.001 | ||
| Other | 192.1 (187.1–197.2) | 0.935 (0.856–1.020) | 0.131 | 0.989 (0.904–1.081) | 0.804 | ||
| Marital status | 14.339 | < 0.001 | < 0.001 | < 0.001 | |||
| Single | 178.5 (174.1–183.0) | Reference | Reference | ||||
| Married | 193.2 (191.2–195.3) | 0.793 (0.739–0.852) | < 0.001 | 0.767 (0.713–0.825) | < 0.001 | ||
| Other | 169.9 (165.7–174.0) | 1.140 (1.049–1.238) | 0.002 | 1.040 (0.954–1.133) | 0.375 | ||
| Histologic type | 76.038 | < 0.001 | < 0.001 | < 0.001 | |||
| Adenocarcinoma | 188.1 (186.4–189.9) | Reference | Reference | ||||
| Mucous tumor | 161.6 (154.3–169.0) | 1.521 (1.376–1.681) | < 0.001 | 1.234 (1.115–1.366) | < 0.001 | ||
| Other | 156.9 (140.4–173.5) | 1.590 (1.245–2.031) | < 0.001 | 1.657 (1.296–2.118) | < 0.001 | ||
| Median household income ($) | 43.851 | < 0.001 | < 0.001 | < 0.001 | |||
| 0–599,999 | 176.6 (172.4–180.9) | Reference | Reference | ||||
| 600,000–799,999 | 185.3 (182.6–188.0) | 0.889 (0.827–0.956) | 0.002 | 0.880 (0.818–0.947) | 0.001 | ||
| 800,000–999,999 | 188.3 (185.1–191.5) | 0.838 (0.775–0.907) | < 0.001 | 0.844 (0.778–0.914) | < 0.001 | ||
| > 1,000,000 | 196.2 (191.8–200.7) | 0.726 (0.659–0.801) | < 0.001 | 0.754 (0.682–0.833) | < 0.001 | ||
| T stage | 345.478 | < 0.001 | < 0.001 | < 0.001 | |||
| T0 | 79.4 (45.5–113.3) | Reference | Reference | ||||
| T1 | 212.8 (204.0–221.5) | 0.293 (0.072–1.197) | 0.087 | 0.189 (0.046–0.772) | 0.020 | ||
| T2 | 212.4 (207.0–217.8) | 0.344 (0.086–1.382) | 0.133 | 0.215 (0.053–0.865) | 0.030 | ||
| T3 | 188.2 (186.3–190.1) | 0.552 (0.138–2.206) | 0.400 | 0.402 (0.100–1.610) | 0.198 | ||
| T4 | 146.9 (141.1–152.6) | 1.055 (0.264–4.226) | 0.939 | 0.765(0.191–3.066) | 0.705 | ||
| N stage | 421.691 | < 0.001 | < 0.001 | < 0.001 | |||
| N0 | 198.8 (196.2–201.3) | Reference | Reference | ||||
| N1 | 191.1 (188.5–193.7) | 1.159 (1.088–1.233) | < 0.001 | 1.439 (1.348–1.535) | < 0.001 | ||
| N2 | 148.9 (144.4–153.3) | 2.199 (2.050–2.358) | < 0.001 | 2.593 (2.413–2.786) | < 0.001 | ||
| Treatment modality | 21.458 | < 0.001 | < 0.001 | < 0.001 | |||
| PreORT group | 188.6 (186.5–190.7) | Reference | Reference | ||||
| PostORT group | 181.2 (178.1–184.3) | 1.146 (1.082–1.214) | < 0.001 | 0.984 (0.924–1.048) | 0.620 | ||
| Chemotherapy | 17.153 | < 0.001 | < 0.001 | < 0.001 | |||
| No | 169.1 (159.8–178.4) | Reference | Reference | ||||
| Yes | 187.3 (185.6–189.0) | 0.756 (0.662–0.864) | < 0.001 | 0.832 (0.726–0.952) | 0.008 | ||
| AJCC stage | 147.703 | < 0.001 | < 0.001 | * | * | ||
| II | 198.8 (196.2–201.3) | Reference | |||||
| III | 179.2 (176.9–181.5) | 1.420 (1.341–1.503) | < 0.001 | ||||
*Degree of freedom reduced because of constant or linearly dependent covariates
Bold indicates that P < 0.05
CI, confidence interval; HR, Hazard ratio; PreORT, preoperative radiotherapy; PostORT, postoperative radiotherapy; AJCC, American Joint Committee on Cancer