Low serum albumin: A significant predictor of reduced survival in patients with chronic heart failure

Abstract

Background: Low serum albumin is common in patients with chronic heart failure (HF). Hypothesis: Albumin may have an impact on clinical outcome in HF. We evaluated the effect of albumin levels on clinical outcome in a real-world cohort of patients with HF. Methods: All patients with HF at a health maintenance organization were followed for cardiac-related hospitalizations and death. Results: A total of 5779 HF patients were included in the study; mean follow-up was 576 days; median serum albumin was 4.0 g/dL (interquartile range 3.7-4.2), and 12% of the patients had hypoalbuminemia (albumin<3.5 g/dL). Low albumin was associated with increasing age, higher urea and C-reactive protein, lower sodium, hemoglobin, iron, less treatment with angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, reduced right ventricular function, and pulmonary hypertension. Cox regression analysis after adjustment for significant predictors demonstrated that decreasing quartiles of albumin was significantly associated with mortality: Lowest quartile compared to highest: hazard ratio (HR) 5.74, 95% confidence interval (CI) 4.08 to 8.07, P < 0.001. Cox regression analysis of albumin as a continuous parameter using restricted cubic splines after adjustment for significant parameters demonstrated that reduced albumin levels were directly associated with increased mortality (P < 0.001 for the adjusted model). Decreasing quartiles of albumin were also a significant predictor of increased cardiac-related hospitalizations. A decrease in albumin on follow-up was an independent predictor of increased mortality by Cox regression analysis: HR 2.58, 95% CI 2.12 to 3.14, P < 0.001. Conclusions: Low albumin provides important information regarding several detrimental processes in HF and is a significant predictor of a worse outcome in these patients.