Table 2.
Overall survival with antibiotic use compared with non-use expressed as a synergy factor between ICI/TKI use
| All-cause mortality | |||||||||
| Immune checkpoint inhibitors (ICI) |
Tyrosine kinase inhibitors (TKI) |
Effect of antibiotic use | Chemoimmunotherapy | Chemotherapy | |||||
| N | aHR (95% CI) | N | aHR (95% CI) | Synergy index (ICI vs TKI) | N | aHR (95% CI) | N | aHR (95% CI) | |
| No antibiotics | 1,314 | Reference | 648 | Reference | – | 101 | Reference | 1,212 | Reference |
| Antibiotic use prior to start of cancer therapy | |||||||||
| ≤30 days before | 174 | 1.26 (1.04 to 1.51) | 82 | 1.24 (0.95 to 1.62) | 0.96 (0.70 to 1.31) | 29 | 1.26 (0.76 to 2.08) | 164 | 1.06 (0.86 to 1.30) |
| 31–90 days before | 127 | 1.51 (1.22 to 1.86) | 37 | 1.18 (0.77 to 1.80) | 1.13 (0.72 to 1.80) | 23 | 1.56 (0.96 to 2.56) | 102 | 0.77 (0.58 to 1.00) |
| 91–365 days before | 189 | 1.47 (1.24 to 1.76) | 31 | 1.68 (1.11 to 2.57) | 0.83 (0.53 to 1.31) | 33 | 1.81 (1.15 to 2.84) | 67 | 1.48 (1.10 to 1.99) |
| >365 days before | 104 | 1.03 (0.81 to 1.30) | 19 | 0.90 (0.53 to 1.52) | 1.17 (0.67 to 2.05) | 7 | 1.21 (0.49 to 3.02) | 71 | 0.98 (0.71 to 1.34) |
| Antibiotic use at any time during cancer therapy | |||||||||
| Oral | 945 | 0.84 (0.76 to 0.92) | 376 | 0.83 (0.71 to 0.98) | 0.92 (0.78 to 1.09) | 130 | 0.69 (0.54 to 0.89) | 812 | 0.73 (0.66 to 0.81) |
| Topical | 88 | 0.75 (0.57 to 1.00) | 63 | 1.03 (0.67 to 1.38) | 0.67 (0.45 to 1.00) | 15 | 0.86 (0.50 to 1.47) | 97 | 1.36 (1.01 to 1.82) |
aHR fully adjusted for age, sex, tumor stage, number/site of metastases, underlying malignant disease, comorbidities, concomitant drug use, baseline organ function, C reactive protein, lactate dehydrogenase, white blood cell count and neutrophil lymphocyte ratio.
aHR, adjusted HR.