Table 2.
Subgroup analysis of the relationship between the ALI and OS
| Subgroup factor | Divided standard | No. of studies | HR (95% CI) | P | Heterogeneity | |
|---|---|---|---|---|---|---|
| I2 (%) | P het | |||||
| Median age (years) | < 60 | 5 | 1.59 (1.24–1.95) | < 0.001 | 0.0 | 0.66 |
| ≥ 60 | 2 | 2.59 (1.56–3.63) | < 0.001 | 0.0 | 0.637 | |
| Not reported | 2 | 1.70 (1.11–2.30) | < 0.001 | 52.9 | 0.145 | |
| Sample size | < 170 | 4 | 2.61 (1.69–3.52) | < 0.001 | 0.0 | 0.614 |
| ≥ 170 | 5 | 1.60 (1.29–1.90) | < 0.001 | 0.0 | 0.749 | |
| Ethnicity | Asian | 6 | 1.80 (1.43–2.18) | < 0.001 | 12 | 0.34 |
| European | 2 | 2.29 (0.97–3.61) | NS | 0.0 | 0.91 | |
| North American | 1 | 1.42 (1.00–2.01) | < 0.001 | – | – | |
| Pathological type | NSCLC | 4 | 1.55 (1.08–2.02) | < 0.001 | 19.2 | 0.29 |
| SCLC | 2 | 1.64 (1.24–2.05) | < 0.001 | 0.0 | 0.898 | |
| Colorectal cancer | 1 | 2.77 (1.77–4.34) | < 0.001 | – | – | |
| Head and neck squamous cell carcinoma | 1 | 2.23 (1.12–4.55) | 0.011 | – | – | |
| Diffuse large B cell lymphoma | 1 | 2.64 (1.54–5.97) | 0.019 | – | – | |
| Clinical stage | Metastatic | 3 | 1.64 (1.18–2.10) | < 0.001 | 52.7 | 0.12 |
| Non-metastatic | 2 | 2.50 (0.78–4.21) | NS | 0.0 | 0.20 | |
| Mixed | 4 | 1.70 (1.31–2.09) | < 0.001 | 0.0 | 0.76 | |
| Treatment | Surgery | 3 | 2.37 (1.15–3.58) | < 0.001 | 0.0 | 0.43 |
| No surgery | 6 | 1.66 (1.36–1.96) | < 0.001 | 0.5 | 0.41 | |
| Cutoff of ALI | < 23.2 | 4 | 1.55 (1.19–1.92) | < 0.001 | 13.7 | 0.32 |
| ≥ 23.2 | 5 | 1.96 (1.47–2.44) | < 0.001 | 0.0 | 0.59 | |
Abbreviations: HR hazard ratio, 95% CI 95% confidence interval, NSCLC non-small cell lung cancer, SCLC small cell lung cancer, Mixed included patients with metastatic and non-metastatic disease, ALI advanced lung cancer inflammation index, NS not significant