Table 2.
Univariate and multivariable analysis of factors associated with BO
| Patient characteristics | Univariate analysis | Multivariate analysis | ||||
|---|---|---|---|---|---|---|
| HR | 95% CI | p value | HR | 95% CI | p value | |
| Gender | ||||||
| Men | 1.087 | 1.013–1.167 | 0.020 | |||
| Women | 1.000 | |||||
| Age at diagnosis, years | ||||||
| 66–70 | 1.818 | 1.642–2.013 | < 0.001 | 1.737 | 1.558–1.935 | < 0.001 |
| 71–75 | 1.765 | 1.605–1.942 | 1.765 | 1.596–1.953 | ||
| 76–80 | 1.636 | 1.490–1.796 | 1.523 | 1.384–1.677 | ||
| ≥ 81 | 1.000 | 1.000 | ||||
| Race | ||||||
| White | 1.000 | 0.001 | 1.000 | 0.004 | ||
| Black | 0.873 | 0.783–0.972 | 0.825 | 0.738–0.922 | ||
| Asian | 1.291 | 1.081–1.542 | 1.062 | 0.887–1.271 | ||
| Other | 0.962 | 0.800–1.156 | 0.887 | 0.737–1.067 | ||
| Marital status | ||||||
| Single + separated | 1.067 | 0.945–1.204 | < 0.001 | 1.058 | 0.936–1.197 | < 0.001 |
| Married | 1.369 | 1.269–1.478 | 1.115 | 1.028–1.208 | ||
| Divorced + widowed | 1.000 | 1.000 | ||||
| Other | 0.565 | 0.468–0.682 | 0.622 | 0.514–0.752 | ||
| Residence location* | ||||||
| Big metro | 1.000 | < 0.001 | 1.000 | 0.050 | ||
| Metro or urban | 0.863 | 0.797–0.933 | 0.906 | 0.837–0.981 | ||
| Less urban or rural | 0.844 | 0.747–0.955 | 0.946 | 0.835–1.072 | ||
| Median household income | ||||||
| 1st quartile | 1.000 | 0.107 | ||||
| 2nd quartile | 1.066 | 0.961–1.183 | ||||
| 3rd quartile | 1.081 | 0.975–1.199 | ||||
| 4th quartile | 1.118 | 1.009–1.239 | ||||
| Unknown | 0.929 | 0.782–1.104 | ||||
| Level of education | ||||||
| 1st quartile | 1.000 | 0.571 | ||||
| 2nd quartile | 0.996 | 0.899–1.102 | ||||
| 3rd quartile | 0.993 | 0.897–1.100 | ||||
| 4th quartile | 0.968 | 0.873–1.072 | ||||
| Unknown | 0.872 | 0.735–1.034 | ||||
| Tumor characteristics | ||||||
| T category | ||||||
| Tis | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| T1 | 1.532 | 1.233–1.904 | 1.434 | 1.144–1.796 | ||
| T2 | 6.878 | 5.396–8.768 | 6.175 | 4.768–7.997 | ||
| T3 | 8.408 | 6.855–10.313 | 7.187 | 5.738–9.003 | ||
| T4a | 15.416 | 11.848–20.059 | 9.064 | 6.824–12.039 | ||
| T4b | 4.566 | 3.626–5.750 | 4.466 | 3.489–5.717 | ||
| Unknown | 1.559 | 1.270–1.913 | 1.562 | 1.257–1.941 | ||
| M category | ||||||
| M0 | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| M1 | 0.665 | 0.598–0.738 | 0.793 | 0.707–0.889 | ||
| Unknown | 0.925 | 0.850–1.007 | 1.213 | 1.108–1.328 | ||
| Primary tumor site | ||||||
| Rectum | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| Left-sided colon | 2.055 | 1.881–2.244 | 2.093 | 1.892–2.315 | ||
| Right-sided colon | 1.445 | 1.326–1.574 | 1.583 | 1.432–1.750 | ||
| Histologic type | ||||||
| Adenocarcinoma | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| Mucinous carcinoma | 2.368 | 2.076–2.701 | 1.593 | 1.392–1.823 | ||
| Signet-ring cell carcinoma | 2.096 | 1.515–2.899 | 1.220 | 0.875–1.701 | ||
| Histologic grade | ||||||
| Well | 0.771 | 0.669–0.889 | < 0.001 | 0.842 | 0.729–0.972 | < 0.001 |
| Moderate | 1.000 | 1.000 | ||||
| Poor | 1.203 | 1.090–1.328 | 1.131 | 1.022–1.251 | ||
| Undifferentiated | 0.954 | 0.652–1.395 | 0.992 | 0.676–1.456 | ||
| Unknown | 0.383 | 0.350–0.419 | 0.548 | 0.498–0.604 | ||
| Tumor size, mm | ||||||
| < 35 | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| 35–50 | 1.734 | 1.526–1.970 | 1.266 | 1.110–1.444 | ||
| 50–65 | 1.269 | 1.114–1.446 | 1.133 | 0.991–1.295 | ||
| ≥ 65 | 1.543 | 1.353–1.759 | 1.253 | 1.093–1.436 | ||
| Unknown | 0.419 | 0.376–0.467 | 0.616 | 0.549–0.690 | ||
| Presenting features | ||||||
| HCC risk score | ||||||
| 1st quartile | 1.000 | < 0.001 | ||||
| 2nd quartile | 1.187 | 1.076–1.309 | ||||
| 3rd quartile | 1.126 | 1.019–1.245 | ||||
| 4th quartile | 0.913 | 0.821–1.015 | ||||
| History of alcoholism | ||||||
| No | 1.000 | 0.011 | 1.000 | 0.027 | ||
| Yes | 0.753 | 0.606–0.937 | 0.781 | 0.627–0.973 | ||
| Tobacco | ||||||
| No | 1.000 | 0.385 | ||||
| Yes | 0.951 | 0.849–1.065 | ||||
| History of colorectal polyps | ||||||
| No | 1.000 | 0.004 | ||||
| Yes | 0.850 | 0.760–0.949 | ||||
| Obesity | ||||||
| No | 1.000 | 0.845 | ||||
| Yes | 0.987 | 0.863–1.128 | ||||
| Treatment | ||||||
| Chemotherapy | ||||||
| Nonchemotherapy | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| 5-FU/capecitabine | 0.758 | 0.677–0.847 | 0.752 | 0.655–0.864 | ||
| FOLFOX/CapeOX | 0.719 | 0.561–0.922 | 0.595 | 0.459–0.770 | ||
| FOLFIRI/XELIRI | 0.729 | 0.559–0.950 | 0.629 | 0.480–0.825 | ||
| FOLFOX/CapeOX + bevacizumab | 0.482 | 0.360–0.645 | 0.395 | 0.292–0.535 | ||
| FOLFIRI/XELIRI + bevacizumab | 0.921 | 0.534–1.589 | 0.980 | 0.564–1.705 | ||
| Other | 0.798 | 0.664–0.958 | 0.715 | 0.590–0.867 | ||
| Radiotherapy | ||||||
| No | 1.000 | < 0.001 | 1.000 | < 0.001 | ||
| Yes | 0.705 | 0.637–0.780 | 0.591 | 0.514–0.679 | ||
| Presenting symptoms | ||||||
| Abdominal pain | ||||||
| No | 1.000 | < 0.001 | < 0.001 | |||
| Yes | 1.179 | 1.087–1.278 | 1.202 | 1.105–1.307 | ||
| Abdominal mass | ||||||
| No | 1.000 | 0.025 | 1.000 | 0.056 | ||
| Yes | 1.230 | 1.026–1.476 | 1.199 | 0.996–1.445 | ||
| Abdominal distension | ||||||
| No | 1.000 | 0.381 | ||||
| Yes | 1.128 | 0.862–1.476 | ||||
| Ascites | ||||||
| No | 1.000 | 0.497 | ||||
| Yes | 0.865 | 0.569–1.315 | ||||
| Anemia | ||||||
| No | 1.000 | < 0.001 | 1.000 | 0.002 | ||
| Yes | 0.736 | 0.642–0.845 | 0.802 | 0.696–0.923 | ||
| Nutritional deficiency | ||||||
| No | 1.000 | < 0.001 | 1.000 | 0.067 | ||
| Yes | 0.624 | 0.513–0.758 | 0.830 | 0.680–1.013 | ||
| Cachexia | ||||||
| No | 1.000 | 0.166 | ||||
| Yes | 0.658 | 0.364–1.189 | ||||
| Change of bowel habit | ||||||
| No | 1.000 | 0.023 | ||||
| Yes | 0.798 | 0.657–0.969 | ||||
| Change of character of stool | ||||||
| No | 1.000 | 0.348 | ||||
| Yes | 1.043 | 0.955–1.138 | ||||
| Hemorrhage | ||||||
| No | 1.000 | < 0.001 | ||||
| Yes | 0.841 | 0.769–0.920 | ||||
| Diarrhea | ||||||
| No | 1.000 | 0.458 | ||||
| Yes | 0.950 | 0.830–1.088 | ||||
| Gatism | ||||||
| No | 1.000 | 0.183 | ||||
| Yes | 0.716 | 0.438–1.170 | ||||
| Loss of appetite | ||||||
| No | 1.000 | 0.002 | 1.000 | 0.077 | ||
| Yes | 0.598 | 0.431–0.831 | 0.742 | 0.533–1.033 | ||
| Vomiting | ||||||
| No | 1.000 | 0.537 | ||||
| Yes | 0.954 | 0.820–1.109 | ||||
| Weight loss | ||||||
| No | 1.000 | 0.579 | ||||
| Yes | 0.965 | 0.852–1.094 | ||||
Abbreviations: BO bowel obstruction, HCC the Centers for Medicare and Medicaid Service’s Hierarchical Condition Category, HR hazard ratio, CI confidence intervals, 5-FU 5-fluorouracil, FOLFOX 5-FU + oxaliplatin, CapeOX capecitabine + oxaliplatin, FOLFIRI 5-FU + irinotecan, and XELIRI capecitabine + irinotecan. *variable has missing data