Association between lactate-to-albumin ratio and short-time mortality in patients with acute respiratory distress syndrome

Abstract

Study objective: The lactate-to-albumin ratio (LAR) has been confirmed to be an effective prognostic marker in sepsis, heart failure, and acute respiratory failure. However, the relationship between LAR and mortality in patients with acute respiratory distress syndrome (ARDS) remains unclear. We aim to evaluate the predictive value of LAR for ARDS patients.

Design: A retrospective cohort study.

Setting: Medical Information Mart for Intensive Care IV (v2.2) database.

Patients: 769 patients with acute respiratory distress syndrome(ARDS).

Interventions: We divided the patients into two subgroups according to the primary study endpoint (28-days all-cause mortality): the 28-day survivors and the 28-day non-survivors.

Measures: Multivariate Cox Regression, Receiver Operator Characteristic (ROC) and Kaplan-Meier survival analysis were used to investigate the relationship between LAR and short-time mortality in patients with ARDS.

Main results: The 28-day mortality was 38 % in this study. Multivariable Cox regression analysis showed that LAR was an independent predictive factor for 28-day mortality (HR 1.11, 95 %CI: 1.06-1.16, P < 0.001). The area under curve (AUC) of LAR in the ROC was 70.34 % (95 %CI: 66.53 % - 74.15 %) that provided significantly higher discrimination compared with lactate (AUC = 68.00 %, P = 0.0007) or albumin (AUC = 63.17 %, P = 0.002) alone. LAR was also not inferior to SAPSII with the AUC of 73.44 % (95 %CI: 69.84 % - 77.04 %, P = 0.21). Additionally, Kaplan-Meier survival analysis displayed that ARDS patients with high LAR (> the cut-off value 0.9055) had a significantly higher 28-day overall mortality rate (P < 0.001) and in-hospital mortality rate (P < 0.001). However, patients in high LAR group had shorter length of hospital stay (P < 0.001), which might be caused by higher in-hospital mortality.

Conclusions: We confirmed that there was a positive correlation between LAR and 28-day mortality. This could provide anesthesiologists and critical care physicians with a more convenient tool than SAPSII without being superior for detecting ARDS patients with poor prognosis timely.

Keywords: 28-day all-cause mortality; Acute respiratory distress syndrome; Lactate-to-albumin ratio.