Incidence and Impact of Hypoalbuminaemia on Outcomes Following Acute Pulmonary Embolism

Abstract

Clinical features and outcomes of patients with hypoalbuminaemia in acute pulmonary embolism (PE) have never been studied. The present study investigated the incidence and determined the prognostic significance of hypoalbuminaemia in patients with confirmed acute PE. From a dedicated tertiary-referral centre database involving 1,426 consecutive patients admitted with confirmed PE (2000-2012), 1,032 patients had serum albumin assessed on admission (day-1). Patients were stratified into hypoalbuminaemia (<35 g/L) or normal serum albumin (≥35 g/L). Multivariable logistic and Cox proportional-hazards regression methods were used to assess 30-day and 90-day all-cause mortality. Hypoalbuminaemia was present in 160 (15.5%) patients at day-1 and was associated with higher mean (±SD) heart rate (94.4 ± 21.8 vs 87.8 ± 21.5 bpm), lower systolic blood pressure (131.0 ± 24.7 vs 142.3 ± 24.7 mmHg), lower arterial oxyhaemoglobin saturation (93.3 ± 6.1% vs 95.6 ± 4.0%), lower day-1 serum sodium (137.0 ± 4.7 vs 138.8 ± 3.8 mmol/L) and haemoglobin levels (114.4 ± 20.7 vs 131.5 ± 18.7 g/L). Patients with hypoalbuminaemia had higher incidence of malignancy (44.4% vs 18.8%) and chronic renal disease (9.4% vs 5.2%), and at admission were less likely to be taking aspirin/clopidogrel (19.3% vs 27.7%) and more likely to be using enoxaparin (6.7% vs 3.0%). During a mean follow-up of 5.0 ± 4.0 years, patients with hypoalbuminaemia had higher 30-day (16.3% vs 3.6%) and 90-day (26.3% vs 6.2%) mortality. Multivariable analyses showed hypoalbuminaemia independently predicted both 30-day (odds ratio 2.57, 95% confidence interval [CI] 1.03-6.41) and 90-day (hazard ratio 2.42 95% CI 1.38-4.22) mortality. Hypoalbuminaemia is an independent predictor of mortality following PE and may improve risk stratification of patients in risk prediction models.