Hyperhomocysteinemia and the MTHFR C677T mutation in Budd-Chiari syndrome

Abstract

Hyperhomocysteinemia (HH) is a factor that predisposes individuals to thrombosis, and the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) is known to give increased plasma homocysteine. However, little is known about their roles in Budd-Chiari syndrome (BCS). This study evaluated the roles of HH and the MTHFR C677T mutation in patients with BCS. We compared 41 BCS patients with 80 sex- and agematched healthy controls. The mean plasma homocysteine level was significantly higher in patients with BCS (20.15 ± 5.78 μmol/L) compared with normal controls (15.80 ± 6.58 μmol/L), P< 0.01. HH (>19.5 μmol/L in men and >15.0 μmol/L in women) was detected in 15 (36.59%) patients and in 14 (17.5%) controls (odds ratio [OR], 2.72; 95% confidence internal [CI], 1.17-6.32). The prevalence of the mutated MTHFR 677TT genotype and the 677T allele in normal controls was 10.0% and 31.3%, respectively. The mutant 677T homozygotes and alleles were more frequent in patients with BCS than in controls (22.0% vs. 10.0%, 0.025 < P< 0.05; 45.1% vs. 31.3%, 0.025 < P< 0.05). The relative risk of BCS among the carriers of 677TT was significantly increased (OR, 3.3; 95% CI, 1.1-10.0). The mutant MTHFR heterozygous 677C/T carriers were not significantly increased in patients with BCS compared with controls (46.3% vs. < 2.5%, P> 0.05). The relative risk OR of BCS among carriers of 677C/T was 1.6 (95% CI, 0.7-3.6). This study suggests that both HH and the homozygous C677T mutation in the MTHFR gene are important risk factors of BCS. © 2002 Wiley-Liss, Inc.