title: Construct validation of the dietary inflammatory index among postmenopausal women.
abstract: OBJECTIVE
  Many dietary factors have either proinflammatory or anti-inflammatory properties. We previously developed a dietary inflammatory index (DII) to assess the inflammatory potential of diet. In this study, we conducted a construct validation of the DII based on data from a food frequency questionnaire and three inflammatory biomarkers in a subsample of 2567 postmenopausal women in the Women's Health Initiative Observational Study.
  
  
  METHODS
  We used multiple linear and logistic regression models, controlling for potential confounders, to test whether baseline DII predicted concentrations of interleukin-6, high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor alpha receptor 2, or an overall biomarker score combining all three inflammatory biomarkers.
  
  
  RESULTS
  The DII was associated with the four biomarkers with beta estimates (95% confidence interval) comparing the highest with lowest DII quintiles as follows: interleukin-6: 1.26 (1.15-1.38), Ptrend < .0001; tumor necrosis factor alpha receptor 2: 81.43 (19.15-143.71), Ptrend = .004; dichotomized hs-CRP (odds ratio for higher vs. lower hs-CRP): 1.30 (0.97-1.67), Ptrend = .34; and the combined inflammatory biomarker score: 0.26 (0.12-0.40), Ptrend = .0001.
  
  
  CONCLUSIONS
  The DII was significantly associated with inflammatory biomarkers. Construct validity of the DII indicates its utility for assessing the inflammatory potential of diet and for expanding its use to include associations with common chronic diseases in future studies.
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, University of South Carolina, Columbia; Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia.
authors.forename: Fred K
authors.initials: FK
authors.lastname: Tabung
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, University of South Carolina, Columbia; Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia; Center for Research in Nutrition and Health Disparities, University of South Carolina, Columbia. Electronic address: ssteck@sc.edu.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Steck
authors.affiliation: Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia.
authors.forename: Jiajia
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Boston.
authors.forename: Yunsheng
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia; Center for Research in Nutrition and Health Disparities, University of South Carolina, Columbia.
authors.forename: Angela D
authors.initials: AD
authors.lastname: Liese
authors.affiliation: Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY.
authors.forename: Ilir
authors.initials: I
authors.lastname: Agalliu
authors.affiliation: Department of Nutritional Sciences, College of Agriculture and Life Sciences, The University of Arizona, Tucson.
authors.forename: Melanie
authors.initials: M
authors.lastname: Hingle
authors.affiliation: Department of Preventive Medicine and the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: Lifang
authors.initials: L
authors.lastname: Hou
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, University of South Carolina, Columbia.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Hurley
authors.affiliation: Department of Medicine, Baylor College of Medicine, Houston, TX.
authors.forename: Li
authors.initials: L
authors.lastname: Jiao
authors.affiliation: Cardiology Division, School of Medicine and Health Sciences, George Washington University, Washington, DC.
authors.forename: Lisa W
authors.initials: LW
authors.lastname: Martin
authors.affiliation: Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, Buffalo.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Millen
authors.affiliation: Department of Epidemiology, School of Medicine, University of California at Irvine, Irvine.
authors.forename: Hannah L
authors.initials: HL
authors.lastname: Park
authors.affiliation: Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Boston.
authors.forename: Milagros C
authors.initials: MC
authors.lastname: Rosal
authors.affiliation: Division of Preventive Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham.
authors.forename: James M
authors.initials: JM
authors.lastname: Shikany
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, University of South Carolina, Columbia; Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia.
authors.forename: Nitin
authors.initials: N
authors.lastname: Shivappa
authors.affiliation: Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Boston.
authors.forename: Judith K
authors.initials: JK
authors.lastname: Ockene
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, University of South Carolina, Columbia; Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia; Center for Research in Nutrition and Health Disparities, University of South Carolina, Columbia.
authors.forename: James R
authors.initials: JR
authors.lastname: Hebert
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000737:chemistry; D004032:Diet; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D016014:Linear Models; D016015:Logistic Models; D008875:Middle Aged; D017698:Postmenopause; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000097:blood
chemical_list: D015415:Biomarkers; C508600:IL6 protein, human; D015850:Interleukin-6; D047889:Receptors, Tumor Necrosis Factor, Type II; C415902:TNFRSF1B protein, human; D002097:C-Reactive Protein
keywords: Construct validation; Dietary inflammatory index; Inflammatory biomarkers; Women's Health Initiative