title: Dietary flavonoid and proanthocyanidin intakes and prostate cancer risk in a prospective cohort of US men.
abstract: Higher dietary intakes of flavonoids and proanthocyanidins have been associated with a lower risk of several cancers. Few prospective epidemiologic studies have examined individual flavonoids and proanthocyanidins in relation to prostate cancer. We examined these associations in a prospective US cohort of 43,268 men with a mean age of 70 years who completed detailed self-administered questionnaires in 1999-2000. During a mean follow-up of 7.8 years, 3,974 total prostate cancers, including 567 high-grade cases and 362 advanced cases, were ascertained. Cox proportional hazards regression models were used to calculate multivariable-adjusted relative risks and 95% confidence intervals. Residual energy-adjusted total flavonoids (for fifth quintile vs. first quintile, relative risk = 1.11, 95% confidence interval: 1.01, 1.23; P for trend = 0.02) and several subclasses were positively associated with overall prostate cancer risk, mostly limited to the top quintile and the first 2 years of follow-up. The associations for total flavonoids, flavan-3-ols, and proanthocyanidins with high-grade prostate cancer risk varied by follow-up time. During follow-up from 2002 to 2009, we observed suggestive inverse trends with higher total flavonoids (P for trend = 0.05) and proanthocyanidins (P for trend = 0.04) with high-grade prostate cancer, but not with advanced prostate cancer. Although evidence is limited, a possible role of total flavonoids and proanthocyanidins in prostate cancer tumor progression deserves further study.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Stevens
authors.forename: Roma
authors.initials: R
authors.lastname: Shah
authors.forename: Julia J
authors.initials: JJ
authors.lastname: Peterson
authors.forename: Johanna T
authors.initials: JT
authors.lastname: Dwyer
authors.forename: Susan M
authors.initials: SM
authors.lastname: Gapstur
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: McCullough
mesh_terms: D000368:Aged; D000975:Antioxidants; D004032:Diet; D004034:Diet Surveys; D005419:Flavonoids; D005500:Follow-Up Studies; D015438:Health Behavior; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D044945:Proanthocyanidins; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D012306:Risk; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D044945:Proanthocyanidins; C013221:proanthocyanidin
keywords: flavonoids; proanthocyanidins; prospective cohort study; prostate cancer