Advanced lung cancer inflammation index is associated with mortality in critically ill patients with heart failure

Aims Nutrition and inflammation status play a vital role in the prognosis of patients with heart failure (HF). This study aimed to investigate the association between the advanced lung cancer inflammation index (ALI), a novel composite indicator of inflammation and nutrition, and short-term mortality among critically ill patients with HF. Methods This retrospective study included 548 critically ill patients with HF from the MIMIC-IV database. ALI was computed using body mass index, serum albumin and neutrophil-lymphocyte ratio. The primary endpoint was all-cause in-hospital mortality, and the secondary endpoint was 90 day mortality. Kaplan-Meier survival curve analysis with long-rank test and Cox proportional hazards regression models were employed to assess the relationship between baseline ALI and short-term mortality risk. The incremental predictive ability of ALI was evaluated by C-statistic, continuous net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Results The average age of 548 patients was 72.2 (61.9, 82.1) years, with 60% being male. Sixty-three patients (11.5%) died in the hospital, and 114 patients (20.8%) died within 90 days of intensive care unit admission. The Kaplan-Meier analysis revealed that the cumulative incidences of both in-hospital and 90 day mortality were significantly higher in patients with lower ALI (log-rank test, in-hospital mortality: P < 0.001; 90 day mortality: P < 0.001). The adjusted Cox proportional hazard model revealed that ALI was inversely associated with both in-hospital and 90 day mortality after adjusting for confounders [hazard ratio (HR) (95% confidence interval) (CI): 0.97 (0.94, 0.99), P = 0.035; HR (95% CI): 0.62 (0.39, 0.99), P = 0.046]. A linear relationship was observed between ALI and in-hospital mortality (P for non-linearity = 0.211). The addition of ALI significantly improved the prognostic ability of GWTG-HF score in the in-hospital mortality [C-statistic improved from 0.62 to 0.68, P = 0.001; continuous NRI (95% CI): 0.44 (0.20, 0.67), P < 0.001; IDI (95% CI): 0.03 (0.01, 0.04), P < 0.001] and 90 day mortality [C-statistic improved from 0.63 to 0.70, P < 0.001; continuous NRI (95% CI): 0.31 (0.11, 0.50), P = 0.002; IDI (95% CI): 0.01 (0.00, 0.02), P = 0.034]. Subgroup analysis revealed stronger correlations between ALI and in-hospital mortality in males and patients aged over 65 years (interaction P = 0.031 and 0.010, respectively). The C-statistic of in-hospital mortality in patients over 65 years was 0.66 (95% CI: 0.58, 0.74). Conclusions ALI at baseline can independently predict the risk of short-term mortality in critically ill patients with HF, with lower ALI significantly associated with higher mortality. Further large prospective research with extended follow-up periods is necessary to validate the findings of this study.