Serum lactate to albumin ratio at hospital arrival and neurological outcome of out-of-hospital cardiac arrest: a nationwide multicenter observational study

Objective We investigated the possible association between serum lactate to albumin ratio upon hospital arrival and out-of-hospital cardiac arrest (OHCA) outcome. Methods Records from the Japanese Association for Acute Medicine–Out-of-Hospital Cardiac Arrest (JAAM-OHCA) Registry were used for this multicenter observational study. Enrolled patients were ≥18 years old with OHCA of medical etiology who were hospitalized after spontaneous circulation returned between June 1, 2014, and December 31, 2021. We excluded those with missing data or those who failed to meet predefined inclusion criteria. The primary outcome was 30-day survival with a favorable neurological outcome, defined as a cerebral performance category score of 1 or 2. Patients were divided into quartiles based on serum lactate to albumin ratios: ≤2.23 (quartile 1), >2.23 and ≤3.39 (quartile 2), >3.39 and ≤4.70 (quartile 3), and >4.70 (quartile 4). The multivariable logistic regression analysis included adjustment for multiple factors. Results Data from 4,413 patients were analyzed. A favorable neurological outcome was achieved by 558 of 1,104 patients (50.5%) in the first quartile, 240 of 1,111 patients (21.6%) in the second quartile, 96 of 1,096 patients (8.8%) in the third quartile, and 24 of 1,102 patients (2.2%) in the fourth quartile. Adjusted odds ratios (95% confidence intervals) for the primary outcome in the second, third, and fourth quartile compared with the first quartile were 0.33 (0.26–0.42), 0.19 (0.14–0.26), and 0.07 (0.04–0.11), respectively. Conclusion The study demonstrated that a lower lactate to albumin ratio was significantly associated with favorable neurological outcomes in patients with out-of-hospital cardiac arrest.