Hyperhomocysteinemia and low B vitamin levels are independently associated with venous thromboembolism: results from the EDITH study: a hospital-based case-control study.

Abstract

Moderate hyperhomocysteinemia and B vitamins deficiency are thought to be risk factors for venous thromboembolism (VTE). The causality and independence of those associations are still questioned. We measured fasting serum total homocysteine, folates, and vitamin B12 levels as well as 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T genotypes in 467 patients hospitalized with a first well-documented deep vein thrombosis and/or pulmonary embolism not related to a major acquired risk factor and 467 controls matched for gender and age. Mild hyperhomocysteinemia, low serum folates, and vitamin B12 were associated with VTE independently of each other. In multivariate analysis, odds ratios (OR) (95% CI) for VTE associated with mild hyperhomocysteinemia (>15 micromol L(-1)), low serum folates (< or = 4.9 nmol L(-1)), and vitamin B12 (< or = 253 pmol L(-1)) were 1.48 (1.05-2.08), 3.14 (1.35-7.32) and 1.42 (1.03-1.98), respectively. An MTHFRC677T genotype was not significantly associated with VTE; OR (95% CI): 1.13 (0.70-1.81) The current data provides further knowledge in the complex relationship between hyperhomocysteinemia, low vitamin levels, and VTE.