title: Riboflavin offers a targeted strategy for managing hypertension in patients with the MTHFR 677TT genotype: a 4-y follow-up.
abstract: BACKGROUND
  We recently reported that the elevated blood pressure (BP) observed in patients with cardiovascular disease who are homozygous for the 677C→T polymorphism (TT genotype) in the gene encoding methylenetetrahydrofolate reductase (MTHFR) was responsive to supplementation with riboflavin-the cofactor for MTHFR.
  
  
  OBJECTIVE
  The objective was to investigate the effect of riboflavin on BP targeted at patients with the TT genotype 4 y after initial investigation, during which time major changes in the clinical guidelines for antihypertensive therapy were introduced.
  
  
  METHODS
  A total of 83 patients (representing all 3 genotypes) who participated in a placebo-controlled riboflavin intervention for 16 wk in 2004 agreed to take part. Nested within this follow-up, those with the TT genotype (n = 31) proceeded to intervention with riboflavin (1.6 mg/d for 16 wk) or placebo, conducted in a crossover style whereby the 2004 treatment groups were reversed.
  
  
  RESULTS
  At follow-up in 2008, as in 2004, patients with the TT genotype had higher systolic BP (P < 0.01), with a nonsignificant trend noted for higher diastolic BP (P = 0.051). Despite the marked changes in antihypertensive therapy that had occurred, BP remained unchanged in patients with the TT genotype at the time of follow-up. Riboflavin supplementation (administered in 2004 and 2008) produced an overall decrease in systolic (-9.2 ± 12.8 mm Hg; P = 0.001) and diastolic (-6.0 ± 9.9 mm Hg; P = 0.003) BP.
  
  
  CONCLUSIONS
  Optimizing riboflavin status offers a low-cost targeted strategy for managing elevated BP in this genetically at-risk group. These findings, if confirmed in the general population, could have important implications for the prevention of hypertension.
authors.affiliation: Northern Ireland Centre for Food and Health, University of Ulster, Coleraine, Northern Ireland, United Kingdom.
authors.forename: Carol P
authors.initials: CP
authors.lastname: Wilson
authors.forename: Mary
authors.initials: M
authors.lastname: Ward
authors.forename: Helene
authors.initials: H
authors.lastname: McNulty
authors.forename: J J
authors.initials: JJ
authors.lastname: Strain
authors.forename: Tom G
authors.initials: TG
authors.lastname: Trouton
authors.forename: Geraldine
authors.initials: G
authors.lastname: Horigan
authors.forename: John
authors.initials: J
authors.lastname: Purvis
authors.forename: John M
authors.initials: JM
authors.lastname: Scott
mesh_terms: D000368:Aged; D000483:Alleles; D000959:Antihypertensive Agents / Q000008:administration & dosage; D001794:Blood Pressure / Q000187:drug effects / Q000235:genetics; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000235:genetics; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000235:genetics*; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012256:Riboflavin / Q000008:administration & dosage*
chemical_list: D000959:Antihypertensive Agents; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D012256:Riboflavin