Table 1.
Subgroup analysis of immunotherapy efficacy in terms of overall survival (OS) between younger age (<65 years) and older age (≥65 years)
| Variables | Number of studies | Number of participants |
Pooled HR (95% CI) |
Test for difference |
||||
|---|---|---|---|---|---|---|---|---|
| All | Age <65 years | Age ≥65 years | All | Age <65 years | Age ≥65 years | P value | ||
| All | 26 | 14 511 | 8344 | 6167 | 0.76 (0.70-0.82) | 0.77 (0.70-0.85) | 0.77 (0.70-0.85) | 0.99 |
| Primary disease site | ||||||||
| NSCLC | 10 | 6008 | 3139 | 2869 | 0.74 (0.65-0.84) | 0.71 (0.61-0.84) | 0.78 (0.68-0.90) | 0.39 |
| Melanoma | 6 | 2792 | 1828 | 964 | 0.71 (0.58-0.86) | 0.76 (0.63-0.92) | 0.72 (0.60-0.87) | 0.68 |
| Other tumors | 10 | 5711 | 3377 | 2334 | 0.80 (0.72-0.89) | 0.83 (0.72-0.97) | 0.78 (0.65-0.94) | 0.61 |
| Type of immunotherapy | ||||||||
| Anti-PD-1/PD-L1 antibody | 18 | 9421 | 5256 | 4165 | 0.74 (0.67-0.81) | 0.77 (0.68-0.87) | 0.71 (0.64-0.79) | 0.36 |
| Anti-CTLA-4 antibody | 7 | 4243 | 2564 | 1679 | 0.82 (0.74-0.92) | 0.82 (0.71-0.94) | 0.93 (0.80-1.07) | 0.23 |
| Combination treatment | 1 | 847 | 524 | 323 | — | — | — | — |
| Line of treatment | ||||||||
| 1 | 11 | 7094 | 3994 | 3100 | 0.73 (0.64-0.85) | 0.74 (0.62-0.89) | 0.81 (0.69-0.95) | 0.49 |
| ≥2 | 15 | 7417 | 4350 | 3067 | 0.77 (0.71-0.83) | 0.79 (0.71-0.87) | 0.74 (0.66-0.83) | 0.45 |
CI, confidence interval; CTLA-4, cytotoxic T-lymphocyte antigen-4; HR, hazard ratio; NSCLC, non-small-cell lung cancer; PD-1, programmed cell death protein 1; PD-L1, programmed death-ligand 1.