Hyperhomocysteinemia as an independent risk factor for silent brain infarction

Objective: To evaluate whether hyperhomocysteinemia is an independent risk factor for silent brain infarction (SBI), and to determine the relationship between homocysteine and folate in each type of methylenetetrahydrofolate reductase ( MTHFR) polymorphism, in order to identify a way of reducing the risk for SBI. Methods: The authors enrolled 161 patients with SBI and 126 healthy people, checked their fasting homocysteine and folate levels, and analyzed for the MTHFR C677T polymorphism. Results: The mean plasma homocysteine level in patients with SBI (12.17 +/- 5.35 mumol/L) was significantly higher than in normal healthy people (9.37 +/- 4.11 mumol/ L; p < 0.05). By subgroup analysis, based on the classification of plasma homocysteine levels as high (≥11.77 μmol/L), moderate (8.71 to 11.76 μmol/L), and low (≤ 8.70 μmol/L), the adjusted OR (AOR) of the high group for SBI was significantly greater than that of the low group ( AOR, 4.78; 95% CI, 2.45 to 9.33). The homocysteine level showed a significant inverse correlation with folate level only in patients with SBI with the MTHFR 677TT genotype ( p < 0.05). Conclusions: This study demonstrates that hyperhomocysteinemia is an independent risk factor for SBI, and provides the possibility of reducing the risk for SBI in the MTHFR 677TT genotype by folate supplementation.