The Effect Of MTHFR C677T Gene Mutation On Hcy Levels In Patients With H-type Hypertension And The Clinical Study Of Low-dose Folic Acid Intervention

Objective: H-type hypertension is a special type of essential hypertension with high homocysteine(Hcy)levels(Hcy?10?mol/L).Hcy is an intermediate of methionine metabolism,and its level is influenced by both genetic and environmental factors.Methylenetetrahydrofolate reductase(MTHFR)is one of the key enzymes in the metabolism of homocysteine,and this enzyme deficiency can affects the methylation of Hcy pathway,leading to the accumulation of a large number of Hcy in the body,resulting in Hyperhomocysteinemia(HHcy),which causes a series of pathophysiological responses.Studies have proven that MTHFR C677 T gene polymorphism is an important factor leading to H-type hypertension.Currently the treatment of high levels of Hcy associated with H-type hypertension is mainly exogenous folic acid supplementation,but its effectiveness is still controversial.Therefore,it is of great value to investigate the effect of MTHFR C677 T polymorphism on plasma homocysteine levels in H-type hypertensive patients and changes of plasma Hcy and folic acid levels after intervention with low-dose folic acid,which provides a feasible therapy to reduce the increased Hcy levels associated with H-type hypertension and may reduce the risk of cardiovascular and cerebrovascular events in patients with H-type hypertension and improve their prognosis.This study selected H-type hypertensive patients as subjects,with blood pressure controlled,to explore the impact of MTHFR C677 T gene mutation on Hcy in patients with H-type hypertension,and the effect of low-dose folic acid intervention on Hcy levels of H-type hypertension patients with different MTHFR C677 T genotype.Methods: A total of 194 H-type hypertensive patients attending the Department of Cardiology at the Second Clinical Medical School of Nanjing Medical University from January 2017 to January 2018 were included in the study.The enrolled patients were controlled within 140/90 mmHg by individualized antihypertensive therapy.Mesuring the blood Hcy levels,folic acid levels,and MTHFR C677 T gene polymorphisms of all patients.According to the MTHFR C677 T gene polymorphism results,patients were included in the CT group,CC group and TT group.All three groups of patients were treated with folic acid tablets(5mg/w).The dietary habits and antihypertensive therapy followed daily and no other drugs containing folic acid or vitamin B family were taken.After 4 weeks,Hcy levels and folic acid levels were measured again.The efficacy of small doses of folic acid in patients with different MTHFR C677T genotypes was compared.Results:1.There were significant differences in baseline Hcy levels and baseline folic acid levels among the CC,CT,and TT groups.Baseline Hcy levels in the TT group were significantly higher than those in the CC and CT groups(P<0.05).There was no significant difference in baseline Hcy level between CC and CT groups(P>0.05).The levels of baseline Hcy in the three groups were respectively CC group:15.59±5.27?mol/L;CT group 16.07±4.8?mol/L;TT group 21.61±13.54?mol/L.Baseline folate levels in the TT group were significantly higher than those in the CC group in the post-hoc multiple comparisons of baseline folate levels in the three groups(P<0.05).However,there was no significant difference in the baseline folate level between the CT group and the CC and TT groups(P>0.05).The baseline folate levels in the three groups were:CC group:13.12±5.45 ng/ml;CT group:11.44±5.57ng/ml;TT group:10.03±5.58 ng/ml.2.After treatment with folic acid 5mg/w orally for one month,the level of Hcy in patients with three genotypes decreased,and the level of folic acid increased.The difference was statistically significant(P<0.05).After the folic acid treatment for one month,the compliance rate of Hcy levels in the three groups was 20.83%,20.39%and 9.30%(P>0.05),respectively.There was no significant difference in the difference of Hcy level and folic acid level between CC,CT and TT(P>0.05).Conclusion:1.MTHFR C677T gene mutation affects Hcy levels in H-type hypertensive patients,and Hcy levels in H-type hypertensive patients with TT homozygous mutant are higher.2.low-dose folic acid treatment can effectively improve the level of folic acid in H-type hypertensive patients and reduce the level of Hcy.On the basis of low-dose folic acid treatment,there was no significant difference in the therapeutic efficacy between patients with different MTHFR C677T genotypes.