Correlation between blood albumin and hospital death and long-term death in ICU patients with heart failure: data from the medical information mart for intensive care III database.

backgroundElevated circulating levels of albumin (ALB) are often associated with improved prognosis in patients with heart failure (HF). However, investigations of its association with hospital death and long-term death in HF patients in the intensive care unit (ICU) are limited.

aimWe examined whether increased blood ALB levels (first value at admission and maximum and minimum values in the ICU) were related to a greater risk of hospital death and long-term death in ICU patients with HF.

methodsFor the first time, we analyzed 4084 ICU patients with HF admitted to the ICU in The Medical Information Mart for Intensive Care III (MIMIC-III) database.

resultsAmong 4084 HF patients, 774 (18.95%), 1056 (25.86%) and 1720 (42.12%) died in the hospital, within 30 days and 1 year, respectively. We conducted a logistic regression analysis and found significant inverse associations between blood ALB concentration and risk of hospital death, 30-day death and 1-year death when the covariates including age, sex, myocardial infarction (MI), hypertension, diabetes, valvular diseases, atrial fibrillation, stroke and chronic kidney disease (CKD) were adjusted. We additionally used a smooth curve for univariate analysis to establish an association between blood ALB concentration and death risk. Surprisingly, we observed U-shaped correlations between blood ALB concentration and hospital mortality, 30-day mortality and 1-year mortality. We found that the "inflection point" for the blood ALB concentration at the lowest risk of death was 3.5 g/dL. We further observed that a higher blood ALB concentration (albumin-max) did not contribute to a reduced risk of death (hospital death, 30-day death and 1-year death) in HF patients with an albumin concentration >3.5 g/dL.

conclusionsA lower blood ALB concentration contributed to a greater risk of hospital death and long-term death in HF patients admitted to the ICU, further suggesting that nutritional support in the ICU is highly important for improving the short-term and long-term mortality of HF patients. However, in HF patients without hypoproteinaemia (>3.5 g/dL), the impact of increased serum ALB on patient prognosis still needs to be demonstrated.