Interaction of lactate/albumin and geriatric nutritional risk index on the all‐cause mortality of elderly patients with critically ill heart failure: A cohort study

BACKGROUND: Whether there is a multiplicative interaction of lactate/albumin (L/A) ratio and geriatric nutritional risk index (GNRI) on the mortality of critically ill elderly patients with heart failure (HF) remains unclear. HYPOTHESIS: To assess the interaction of L/A ratio and GNRI on the all‐cause mortality in critically ill elderly patients with HF. METHODS: This was a retrospective cohort study and data were extracted from the Medical Information Mart for Intensive Care III (MIMIC‐III) database. The endpoints were 28‐day and 1‐year all‐cause mortality, and the independent variables were L/A ratio and GNRI. The multiplicative interaction of L/A ratio and GNRI on the mortality was examined using Cox proportional‐hazards model. RESULTS: A total of 5627 patients were finally included. Results showed that patients with higher L/A ratio or GNRI ≤ 58 had higher risk of 28‐day and 1‐year all‐cause mortality (all p < .01). We also found the significant multiplicative interaction effect between L/A ratio and GNRI score on the 28‐day and 1‐year all‐cause mortality (both p < .05). The increased L/A ratio was associated with higher risk of 28‐day and 1‐year all‐cause mortality in patients with GNRI ≤ 58 than those with GNRI > 58. CONCLUSIONS: There was a multiplicative interaction effect between L/A ratio and GNRI score on the mortality, and low GNRI score was associated with the increased risk of all‐cause mortality with the increase of L/A ratio, suggesting the importance of nutrition‐oriented intervention in critically ill elderly HF patients with high L/A ratio.