[A case-control study on the relationship between abnormal homocysteine metabolism and essential hypertension]

To examine the relationship between abnormal homocysteine metabolism and essential hypertension in a Chinese population, a community-based case-control study was conducted.

127 essential hypertensive patients aged 35 to 75 were randomly selected from a community. Another 170 control subjects with blood pressure < 140/90 mmHg were selected from the same community. Serum homocysteine was determined using HPLC. Folate and vitamin B(12) were measured by radioimmunoassay. MTHFR genotypes were identified by PCR and restriction fragment length polymorphism analysis with Hinf I digestion.

After adjusting for age and sex, the mean homocysteine level was 10.56 micromol/L for hypertensive patients and 10.34 micromol/L for controls (F = 0.234, P = 0.63). No association between either SBP or DBP and Hcy concentration was found in subjects without anti-hypertensive medications. The prevalence of homozygousity for thermolabile MTHFR variant for this population was 13.1%, and the mutant allele frequency was 38.7%. There was no significant difference on genotype distributions and the mutant allele frequency for the two studied groups. However, the concentrations of folate and B(12) for the hypertensive subjects were generally higher than the controls.

The present study did not discover that the elevation of Hcy levels or MTHFR mutation were independent risk factors for essential hypertension. The higher folate and B(12) in the hypertensive subjects might contribute to a lower risk.