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

BackgroundWhether 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. HypothesisTo assess the interaction of L/A ratio and GNRI on the all-cause mortality in critically ill elderly patients with HF. MethodsThis 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. ResultsA 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. ConclusionsThere 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.