Risk of venous thromboembolism and arterial events in patients with hypoalbuminemia: a comprehensive meta-analysis of more than 2 million of patients

Abstract

Albumin has antiplatelet and anticoagulant functions. Hypoalbuminemia, as defined by serum values <3.5 g/dl is associated with arterial thrombosis; its impact with venous thromboembolism (VTE) is unclear. The objective of this meta-analysis is to assess the VTE risk in patients with hypoalbuminemia. MEDLINE and EMBASE were searched up to January 2024 for observational studies and randomized trials reporting data of interest. Primary outcome was the risk of VTE while secondary outcome was myocardial infarction and stroke risk in patients with versus without hypoalbuminemia. The risk of bias was evaluated using Newcastle-Ottawa scale and Cochrane tool. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated in a random-effects model. 43 studies for a total of 2,531,091 patients (39,738 medical, 2,491,353 surgical) were included in primary analysis; 79.1% of the studies used 3.5 g/dl cut-off value for hypoalbuminemia definition. Follow-up duration was 30 days in 60.5% of studies. Patients with hypoalbuminemia had a higher risk of VTE (RR, 1.88; 95%CI, 1.66-2.13). RR were similar in both medical (RR, 1.87; 95%CI, 1.53-2.27) and surgical patients (RR, 1.87; 95%CI, 1.61-2.16) and in patients with (RR, 1.86; 95%CI, 1.66-2.10) and without cancer (RR, 1.89; 95%CI, 1.47-2.44). Risk of myocardial infarction (RR, 1.88; 95%CI, 1.54-2.31) and stroke (RR 1.77; 95%CI, 1.26-2.48) was higher in patients with hypoalbuminemia. Hypoalbuminemia is a risk factor for VTE in both medical and surgical patients irrespective of cancer coexistence. Serum albumin analysis may represent a simple and cheap tool to identify patients at VTE risk.