title: Vitamin B-6 catabolism and long-term mortality risk in patients with coronary artery disease.
abstract: Low vitamin B-6 status has been related to increased risk of coronary artery disease (CAD), which is a condition that is associated with inflammation. The most common status marker, plasma pyridoxal 5'-phosphate (PLP), decreases during inflammation; therefore, causal relations are uncertain.
  
  
  
  We evaluated the vitamin B-6 biomarkers PLP, pyridoxal, and pyridoxic acid (PA) and the pyridoxic acid:(pyridoxal + PLP) ratio (PAr), a proposed marker of vitamin B-6 catabolism during activated cellular immunity, as predictors of mortality.
  
  
  
  Associations with risks of long-term all-cause mortality and cardiovascular mortality were evaluated with the use of Cox regression in patients who were undergoing elective coronary angiography for suspected stable angina pectoris (SAP) (n = 4131) and an independent cohort of patients who were hospitalized for acute myocardial infarction (AMI) (n = 3665).
  
  
  
  Plasma PLP (AMI patients only) and PA predicted all-cause mortality in models that were adjusted for established risk predictors, but associations were attenuated or nonsignificant after additional adjustment for inflammatory markers. PAr was correlated with biomarkers of inflammation (Pearson's r ≥ 0.37) and predicted all-cause mortality and cardiovascular mortality after adjustment for established risk predictors. In SAP patients, PAr had greater predictive strength than did current smoking, diabetes, hypertension, apolipoproteins, or C-reactive protein. PAr provided multiadjusted HRs per SD of 1.45 (95% CI: 1.30, 1.63) and 1.31 (95% CI: 1.21, 1.41) in SAP and AMI patients, respectively. In both cohorts, PAr was a particularly strong predictor of all-cause mortality for patients with no previous CAD history (P-interaction ≤ 0.04).
  
  
  
  PAr may capture unique aspects of inflammatory activation and thus provide new insights into disease mechanisms that may aid in identifying patients at increased risk of future fatal events.
authors.affiliation: Bevital AS, Bergen, Norway; arve.ulvik@farm.uib.no.
authors.forename: Arve
authors.initials: A
authors.lastname: Ulvik
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway; and.
authors.forename: Eva R
authors.initials: ER
authors.lastname: Pedersen
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway; and.
authors.forename: Gard Ft
authors.initials: GF
authors.lastname: Svingen
authors.affiliation: Bevital AS, Bergen, Norway;
authors.forename: Adrian
authors.initials: A
authors.lastname: McCann
authors.affiliation: Bevital AS, Bergen, Norway;
authors.forename: Øivind
authors.initials: Ø
authors.lastname: Midttun
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway; and Department of Heart Disease and.
authors.forename: Ottar
authors.initials: O
authors.lastname: Nygård
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway; and Laboratory of Ok Clinical Biochemistry, Haukeland University Hospital, Bergen, Norway.
authors.forename: Per M
authors.initials: PM
authors.lastname: Ueland
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis; D003324:Coronary Artery Disease / Q000097:blood* / Q000401:mortality*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009203:Myocardial Infarction / Q000097:blood; D011730:Pyridoxal / Q000097:blood; D011732:Pyridoxal Phosphate / Q000097:blood; D011735:Pyridoxic Acid / Q000097:blood; D012307:Risk Factors; D025101:Vitamin B 6 / Q000097:blood*
chemical_list: D015415:Biomarkers; D011730:Pyridoxal; D011735:Pyridoxic Acid; D011732:Pyridoxal Phosphate; D025101:Vitamin B 6; D002097:C-Reactive Protein
keywords: biomarker; coronary artery disease; inflammation; mortality; vitamin B-6