Reliability of fasting plasma alkylresorcinol metabolites concentrations measured 4 months apart.
Alkylresorcinols (AR) have been suggested as specific dietary biomarkers of whole-grain wheat and rye intake. AR are metabolised to 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), which have longer apparent half-lives and were recently proposed to better reflect long-term whole-grain consumption than the intact AR. The objective of this study was to analyse the reliability--expressed by the intraclass correlation coefficient (ICC)--of AR metabolite concentrations among 100 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study who provided two fasting plasma samples 4 months apart. DHBA and DHPPA concentrations were not significantly different between the first and second measurement over the 4-month period (P>0.05). The ICC was 0.32 (95% confidence interval (CI)=0.13-0.49) for DHBA and 0.37 (95%CI=0.19-0.53) for DHPPA. These results suggest that AR metabolites cannot be considered to be better biomarkers of whole-grain wheat and rye intake than the intact AR in fasting plasma (ICC=0.42).
Department of Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany.
J
J
Montonen
R
R
Landberg
A
A
Kamal-Eldin
P
P
Åman
H
H
Boeing
A
A
Steffen
T
T
Pischon
D015415:Biomarkers / Q000097:blood*; D002396:Catechols / Q000097:blood*; D005215:Fasting; D005260:Female; D006801:Humans; D062385:Hydroxybenzoates; D008297:Male; D008875:Middle Aged; D010667:Phenylpyruvic Acids / Q000097:blood*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012118:Resorcinols / Q000097:blood* / Q000378:metabolism; D012434:Secale / Q000737:chemistry; D013997:Time Factors; D014908:Triticum / Q000737:chemistry
D015415:Biomarkers; D002396:Catechols; D062385:Hydroxybenzoates; D010667:Phenylpyruvic Acids; D012118:Resorcinols; C019344:3,4-dihydroxyphenylpyruvic acid; C009135:2,3-dihydroxybenzoic acid