Table 2.
Univariable Cox Regression | Multivariable Cox Regression | ||||||||
---|---|---|---|---|---|---|---|---|---|
95%-CI | 95%-CI | ||||||||
p | HR | Lower | Upper | p | HR | Lower | Upper | ||
Statin use | No | 1.000 | 1.000 | ||||||
Yes | 0.418 | 0.869 | 0.619 | 1.220 | 0.023 | 0.664 | 0.467 | 0.945 | |
Sex | Female | 1.000 | |||||||
Male | 0.844 | 0.974 | 0.746 | 1.271 | |||||
Age at diagnosis | 50–59 | <0.001 * | 0.059 | 1.000 | |||||
60–69 | 0.374 | 1.139 | 0.855 | 1.519 | 0.820 | 1.035 | 0.773 | 1.385 | |
70+ | <0.001 | 1.902 | 1.418 | 2.552 | 0.027 | 1.417 | 1.041 | 1.929 | |
CCI | 0 | <0.001 | 1.000 | <.001 | 1.000 | ||||
1 | 0.064 | 1.357 | 0.983 | 1.872 | 0.063 | 1.362 | 0.983 | 1.887 | |
2 | 0.002 | 1.757 | 1.236 | 2.499 | 0.001 | 1.814 | 1.262 | 2.606 | |
3+ | <.001 | 2.590 | 1.892 | 3.544 | <.001 | 2.413 | 1.734 | 3.357 | |
Positive anamnesis smoking | No | 1.000 | |||||||
Yes | 0.551 | 1.090 | 0.822 | 1.445 | |||||
Positive anamnesis alcohol | No | 1.000 | |||||||
Yes | 0.784 | 1.037 | 0.799 | 1.346 | |||||
Acetylsalicylic acid use | No | 1.000 | |||||||
Yes | 0.223 | 1.179 | 0.905 | 1.536 | |||||
Metformine use | No | 1.000 | |||||||
Yes | 0.966 | 0.989 | 0.596 | 1.642 | |||||
Anatomical site | Upper alveolus and gingiva & Hard palate | 0.495 | 1.000 | ||||||
Tongue | 0.428 | 0.833 | 0.530 | 1.309 | |||||
Buccal mucosa & Lower alveolus and gingiva & Floor of mouth | 0.950 | 0.987 | 0.659 | 1.480 | |||||
UICC stage | I & II | 1.000 | 1.000 | ||||||
III & IV | <0.001 | 2.288 | 1.782 | 2.939 | <0.001 | 2.054 | 1.586 | 2.660 | |
Grading | G1 | 1.000 | 1.000 | ||||||
G3/4 | 0.065 | 1.326 | 0.983 | 1.789 | 0.324 | 1.170 | 0.856 | 1.598 | |
Lymphatic invasion | L0 | 1.000 | 1.000 | ||||||
L1 | <0.001 | 2.277 | 1.689 | 3.071 | <0.001 | 1.763 | 1.286 | 2.415 | |
Vascular invasion | V0 | 1.000 | 1.000 | ||||||
V1 | 0.001 | 2.339 | 1.410 | 3.881 | 0.231 | 1.387 | 0.812 | 2.368 | |
Adjuvant therapy | No | <0.001 | 1.000 | ||||||
Radiotherapy | <0.001 | 1.754 | 1.353 | 2.273 | |||||
Radiochemotherapy | 0.058 | 1.430 | 0.989 | 2.068 |
Abbreviations: CCI: Charlson comorbidity index; UICC: Union for International Cancer Control; HR: hazard ratio; CI: confidence interval; OAS: overall survival; RFS: recurrence-free survival. Multivariable analysis adjusted for age, CCI, UICC stage, grading, lymphatic and vascular invasion, which proved to have p < 0.100 in univariable analysis. Tumor size, cervical lymph node metastasis and extranodal spread were dismissed in favor of UICC stage. Adjuvant therapy was not regarded as a confounder in this context (variables selected for multivariable analysis and for propensity score matching are highlighted in bold). * p-value in line of reference group denotes significance of the whole variable’s effect.