Association of Serum Albumin with Heart Failure Mortality with NYHA Class IV in Chinese Patients: Insights from PhysioNet Database

Aims: Studies have proved that low albumin level is associated with increased mortality in most diseases, such as chronic kidney disease and hepatic cirrhosis. However, the relationship between albumin and all-cause death in heart failure patients in China is still unclear. We aimed to investigate the association between albumin levels and 28-day mortality in Chinese hospitalized patients with NYHA IV heart failure. Methods: A total of 2008 Chinese patients were included. The correlation between serum albumin level and mortality was tested using a cox proportional hazards regression model. The smooth curve fitting was used to identify non-linear relationships between serum albumin and mortality. The Forest plot analysis was used to assess the association between albumin and 28-day mortality in different groups. Results: Compared with patients with NYHA II-III, patients with NYHA IV had lower albumin levels and higher mortality within 28 days. The albumin on admission was independently and inversely associated with the endpoint risk, which remained significant (hazard ratio: 0.80; 95% confidence interval: 0.66 to 0.96; p = 0.0196) after multivariable adjustment. The smooth curve fitting showed with the increase of albumin, the mortality within 28 days would decrease. A subgroup analysis found that the inverse association between the albumin levels and risk of the mortality was consistent across the subgroup stratified by possible influence factors. Conclusion: Serum albumin level is negatively associated with 28-day mortality in hospitalized heart failure patients within NYHA IV in China, which can be used as an independent predictor.