title: Carbohydrate intake, glycemic index and prostate cancer risk.
abstract: BACKGROUND
  Reported associations between dietary carbohydrate and prostate cancer (PC) risk are poorly characterized by race.
  
  
  METHODS
  We analyzed the association between carbohydrate intake, glycemic index (GI), and PC risk in a study of white (N = 262) and black (N = 168) veterans at the Durham VA Hospital. Cases were 156 men with biopsy-confirmed PC and controls (N = 274) had a PSA test but were not recommended for biopsy. Diet was assessed before biopsy with a self-administered food frequency questionnaire. Logistic regression models were used to estimate PC risk.
  
  
  RESULTS
  In multivariable analyzes, higher carbohydrate intake, measured as percent of energy from carbohydrates, was associated with reduced PC risk (3rd vs. 1st tertile, OR = 0.41, 95% CI 0.21-0.81, P = 0.010), though this only reached significance in white men (p-trend = 0.029). GI was unrelated to PC risk among all men, but suggestively linked with reduced PC risk in white men (p-trend = 0.066) and increased PC risk in black men (p-trend = 0.172), however, the associations were not significant. Fiber intake was not associated with PC risk (all p-trends > 0.55). Higher carbohydrate intake was associated with reduced risk of high-grade (p-trend = 0.016), but not low-grade PC (p-trend = 0.593).
  
  
  CONCLUSIONS
  Higher carbohydrate intake may be associated with reduced risk of overall and high-grade PC. Future larger studies are needed to confirm these findings.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Clinical Epidemiologic Research, Program of Cancer Detection, Prevention and Control, Duke University School of Medicine, Durham, North Carolina; Section of Urology, Department of Surgery, Durham VA Medical Center, Durham, North Carolina; Duke Prostate Center, Division of Urology, Department of Surgery, Duke University Medical Center, Durham, North Carolina.
authors.forename: Adriana C
authors.initials: AC
authors.lastname: Vidal
authors.forename: Christina D
authors.initials: CD
authors.lastname: Williams
authors.forename: Emma H
authors.initials: EH
authors.lastname: Allott
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Howard
authors.forename: Delores J
authors.initials: DJ
authors.lastname: Grant
authors.forename: Megan
authors.initials: M
authors.lastname: McPhail
authors.forename: Katharine N
authors.initials: KN
authors.lastname: Sourbeer
authors.forename: Lin Pao
authors.initials: LP
authors.lastname: Hwa
authors.forename: Paolo
authors.initials: P
authors.lastname: Boffetta
authors.forename: Cathrine
authors.initials: C
authors.lastname: Hoyo
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Freedland
mesh_terms: D000368:Aged; D044383:Black People; D016022:Case-Control Studies; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000009:adverse effects*; D038321:Glycemic Index; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000209:etiology*; D012306:Risk; D011795:Surveys and Questionnaires; D044465:White People
chemical_list: D004040:Dietary Carbohydrates
keywords: carbohydrates; glycemic index; prostate cancer