Albumin level as an independent predictive factor for adverse outcomes in COVID-19 patients: a retrospective cohort study

Abstract

Introduction: Research on the association between albumin (ALB) level and clinical outcomes of coronavirus disease 2019 (COVID-19) are limited. This study aimed to investigate the relationship between albumin level at the time of admission and adverse outcomes in patients with COVID-19.

Methodology: This was a retrospective cohort study with 199 COVID-19 patients from five designated hospitals in Fujian Province who were enrolled between 22 January and 27 February, 2020. Clinical characteristics and laboratory values at the time of admission were collected. Adverse outcomes were defined as meeting at least one of the following criteria: development of acute respiratory distress syndrome (ARDS), respiratory failure, shock, multiple organ failure (MOF), intensive care unit (ICU) admission and in-hospital mortality event. The univariate and multivariate linear regression models and generalized additive models (GAM) were used to analyze the relationship between ALB and adverse outcomes.

Results: A non-linear relationship with an inflection point of 32.6g/L was detected between ALB and adverse outcomes after adjusting for potential confounders. The odds ratio and the confidence intervals on the left and right sides of the inflection point were 0.204 (0.061-0.681) and 0.908 (0.686-1.203), respectively. This suggested that ALB was negatively correlated with adverse outcomes when ALB was less than 32.6 g/L, and for every 1 unit increase in ALB, the risk of adverse outcomes was reduced by 79.6%.

Conclusions: The relationship between ALB and adverse outcomes of COVID-19 is non-linear. ALB level is an independent predictive factor for adverse outcomes in COVID-19 patients.