title: Higher plasma homocysteine is associated with lower vitamin B6 status in critically ill surgical patients.
abstract: BACKGROUND
  Hyperhomocysteinemia might be at least partially due to compromised B vitamin status in critically ill patients and has been linked with critical illness. This study was conducted to examine the association between plasma homocysteine with B vitamins and clinical outcomes in critically ill surgical patients.
  
  
  METHODS
  Thirty-two patients in the surgical intensive care unit (SICU) were enrolled. Disease severity (Acute Physiology and Chronic Health Evaluation II score), hematological values, serum and erythrocyte folate, serum vitamin B₁₂, plasma, and erythrocyte pyridoxal 5'-phosphate (PLP) were determined within 24 hours of admission and again after 7 days.
  
  
  RESULTS
  The prevalence of hyperhomocysteinemia in the patients was either 46.9% (plasma homocysteine ≥12 µmol/L) or 31.3% (plasma homocysteine ≥15 µmol/L) on day 1 in the SICU and increased to 62.5% (plasma homocysteine ≥12 µmol/L) and 37.5% (plasma homocysteine ≥15 µmol/L) on day 7 after admission to the SICU. Plasma homocysteine, serum folate, and vitamin B₁₂ significantly increased by day 7, whereas plasma and erythrocyte PLP remained constant throughout the study. Plasma homocysteine was not correlated with serum folate and vitamin B₁₂. However, plasma and erythrocyte PLP on day 1 were adversely associated with day 1 levels of plasma homocysteine after adjusting for potential confounders. Plasma homocysteine on day 1 or changes (Δ day 7-day 1) did not show any association with clinical outcomes.
  
  
  CONCLUSIONS
  Lower plasma PLP might be a significant factor for increased plasma homocysteine in critically ill surgical patients. The association between plasma homocysteine and clinical outcomes was not found.
authors.affiliation: Critical Care, Changhua Christian Hospital, Changhua, Taiwan.
authors.forename: Chen-Tai
authors.initials: CT
authors.lastname: Hou
authors.forename: Ying-Hsun
authors.initials: YH
authors.lastname: Wu
authors.forename: Chien-Hsiang
authors.initials: CH
authors.lastname: Cheng
authors.forename: Pei-Ning
authors.initials: PN
authors.lastname: Huang
authors.forename: Yi-Chia
authors.initials: YC
authors.lastname: Huang
mesh_terms: D000368:Aged; D016638:Critical Illness; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000097:blood / Q000209:etiology*; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D011183:Postoperative Complications / Q000097:blood*; D015995:Prevalence; D011732:Pyridoxal Phosphate / Q000097:blood*; D014805:Vitamin B 12 / Q000097:blood; D026681:Vitamin B 6 Deficiency / Q000097:blood / Q000150:complications*; D014803:Vitamin B Complex / Q000097:blood*
chemical_list: D006710:Homocysteine; D014803:Vitamin B Complex; D011732:Pyridoxal Phosphate; D005492:Folic Acid; D014805:Vitamin B 12