title: Dietary inflammatory index and risk of renal cancer in the Iowa Women's Health Study.
abstract: BACKGROUND
  The association between inflammatory potential of diet and renal cancer risk has not been investigated.
  
  
  METHODS
  In this study, we explored the association between the dietary inflammatory index (DII) and risk of renal cancer in the Iowa Women's Health Study. From 1986 to 2011, 33,817 women initially recruited at 55-69 years of age were followed for incident renal cancers (n = 263). The DII was computed based on dietary intake assessed using a reproducible and valid 121-item food frequency questionnaire. Cox proportional hazards regression was used to estimate hazard ratios (HR) adjusting for age, body mass index, energy intake, smoking status, education, pack years of smoking, hypertension, and hormone replacement therapy.
  
  
  RESULTS
  Multivariable analyses revealed positive association between higher DII scores and renal cancer risk (HR for DIIcontinuous: 1.07 per unit increase in DII (corresponding to 10% change in the DII range in the current study); 95% CI 1.00, 1.15; HR for DIItertile3vs1= 1.52; 95% CI 1.09, 2.13). Stratified analyses produced slightly stronger associations between DII and renal cancer risk among women with BMI <30 kg/m2(HRTertile3vs1= 1.57; 95% CI = 1.04, 2.36) and ever smokers (HRtertile3vs1= 2.35; 95% CI = 1.22, 4.55), although the corresponding interaction p values were not significant.
  
  
  CONCLUSIONS
  Pro-inflammatory diet, as indicated by higher DII scores, was associated with increased renal cancer risk.
authors.affiliation: Cancer Prevention and Control Program, University of South Carolina, Columbia, SC, 29208, USA. shivappa@mailbox.sc.edu.|Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA. shivappa@mailbox.sc.edu.|Connecting Health Innovation, 1417 Gregg St, Columbia, SC, 29250, USA. shivappa@mailbox.sc.edu.
authors.forename: Nitin
authors.initials: N
authors.lastname: Shivappa
authors.affiliation: Department of Internal Medicine, University of New Mexico, Albuquerque, NM, 87131, USA.|University of New Mexico Comprehensive Cancer Center, Albuquerque, NM, 87131, USA.
authors.forename: Cindy K
authors.initials: CK
authors.lastname: Blair
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, 55454, USA.|Masonic Cancer Center, University of Minnesota, Minneapolis, MN, 55455, USA.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Prizment
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, 55454, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.affiliation: Cancer Prevention and Control Program, University of South Carolina, Columbia, SC, 29208, USA.|Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA.|Connecting Health Innovation, 1417 Gregg St, Columbia, SC, 29250, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Hébert
mesh_terms: D000368:Aged; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D004032:Diet / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007107:Immune System / Q000276:immunology / Q000503:physiopathology*; D007154:Immune System Diseases / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D015994:Incidence; D007484:Iowa / Q000453:epidemiology; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D008875:Middle Aged; D018448:Models, Immunological; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D057566:Self Report
keywords: Cohort; Diet; Dietary inflammatory index (DII); Inflammation; Renal cancer risk