title: Validation of the omega-3 fatty acid intake measured by a web-based food frequency questionnaire against omega-3 fatty acids in red blood cells in men with prostate cancer.
abstract: OBJECTIVE
  The objective of this study was to evaluate the ability of a web-based self-administered food frequency questionnaire (web-FFQ) to assess the omega-3 (ω-3) fatty acids (FAs) intake of men affected with prostate cancer (PCa) against a biomarker.
  
  
  METHODS
  The study presented herein is a sub-study from a phase II clinical trial. Enrolled patients afflicted with PCa were included in the sub-study analysis if the FA profiles from the red blood cell (RBC) membranes and FA intakes at baseline were both determined at the time of the data analysis (n=60). Spearman's correlation coefficients were calculated to estimate the correlations between FA intakes and their proportions in the RBC membranes.
  
  
  RESULTS
  Intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were highly correlated with their respective proportions in the RBC membranes (both rs=0.593, P<0.0001). Correlation between alpha-linolenic acid (ALA) intake and its proportion in RBC was not significant (rs=0.130, P=0.332). Correlations were observed between fatty fish intake and total ω-3 FAs (rs=0.304, P=0.02), total long-chain ω-3 FAs (rs=0.290, P=0.03) and DHA (rs=0.328, P=0.01) in RBC membranes.
  
  
  CONCLUSIONS
  This study has shown that the web-FFQ is an accurate tool to assess total long-chain ω-3 FAs, EPA and DHA but not ALA intake in clinical trials and epidemiological studies carried out in men with PCa.
authors.affiliation: Department of Surgery (Urology), CHU de Québec, L'Hôtel-Dieu de Quebec, Quebec City, Canada.|CHU de Québec, Research Center, Oncology Axis, CHU de Québec, Laval University, Quebec City, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Allaire
authors.affiliation: Department of Surgery (Urology), CHU de Québec, L'Hôtel-Dieu de Quebec, Quebec City, Canada.|CHU de Québec, Research Center, Oncology Axis, CHU de Québec, Laval University, Quebec City, Canada.
authors.forename: X
authors.initials: X
authors.lastname: Moreel
authors.affiliation: Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada.
authors.forename: M-È
authors.initials: MÈ
authors.lastname: Labonté
authors.affiliation: Department of Surgery (Urology), CHU de Québec, L'Hôtel-Dieu de Quebec, Quebec City, Canada.|CHU de Québec, Research Center, Oncology Axis, CHU de Québec, Laval University, Quebec City, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Léger
authors.affiliation: Department of Surgery (Urology), CHU de Québec, L'Hôtel-Dieu de Quebec, Quebec City, Canada.|CHU de Québec, Research Center, Oncology Axis, CHU de Québec, Laval University, Quebec City, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Caron
authors.affiliation: CHU de Québec Research Center, Endocrinology and Nephrology Axis, CHU de Québec, Laval University, Quebec City, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Julien
authors.affiliation: Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada.
authors.forename: B
authors.initials: B
authors.lastname: Lamarche
authors.affiliation: Department of Surgery (Urology), CHU de Québec, L'Hôtel-Dieu de Quebec, Quebec City, Canada.|CHU de Québec, Research Center, Oncology Axis, CHU de Québec, Laval University, Quebec City, Canada.|Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada.
authors.forename: V
authors.initials: V
authors.lastname: Fradet
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D004034:Diet Surveys / Q000379:methods / Q000706:statistics & numerical data*; D004435:Eating; D004912:Erythrocytes / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005396:Fish Products / Q000032:analysis; D005504:Food Analysis / Q000706:statistics & numerical data*; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000097:blood*; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric
chemical_list: D015415:Biomarkers; D015525:Fatty Acids, Omega-3