title: Choline intake and risk of lethal prostate cancer: incidence and survival.
abstract: BACKGROUND
  Meat, milk, and eggs have been inconsistently associated with the risk of advanced prostate cancer. These foods are sources of choline-a nutrient that may affect prostate cancer progression through cell membrane function and one-carbon metabolism. No study has examined dietary choline and the risk of lethal prostate cancer.
  
  
  OBJECTIVE
  Our objective was to examine whether dietary choline, choline-containing compounds, and betaine (a choline metabolite) increase the risk of lethal prostate cancer.
  
  
  METHODS
  We prospectively examined the intake of these nutrients and the risk of lethal prostate cancer among 47,896 men in the Health Professionals Follow-Up Study. In a case-only survival analysis, we examined the postdiagnostic intake of these nutrients and the risk of lethal prostate cancer among 4282 men with an initial diagnosis of nonmetastatic disease during follow-up. Diet was assessed with a validated questionnaire 6 times during 22 y of follow-up.
  
  
  RESULTS
  In the incidence analysis, we observed 695 lethal prostate cancers during 879,627 person-years. Men in the highest quintile of choline intake had a 70% increased risk of lethal prostate cancer (HR: 1.70; 95% CI: 1.18, 2.45; P-trend = 0.005). In the case-only survival analysis, we observed 271 lethal cases during 33,679 person-years. Postdiagnostic choline intake was not statistically significantly associated with the risk of lethal prostate cancer (HR for quintile 5 compared with quintile 1: 1.69; 95% CI: 0.93, 3.09; P-trend = 0.20).
  
  
  CONCLUSIONS
  Of the 47,896 men in our study population, choline intake was associated with an increased risk of lethal prostate cancer.
authors.affiliation: Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA, USA. richmane@urology.ucsf.edu
authors.forename: Erin L
authors.initials: EL
authors.lastname: Richman
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Kenfield
authors.forename: Meir J
authors.initials: MJ
authors.lastname: Stampfer
authors.forename: Edward L
authors.initials: EL
authors.lastname: Giovannucci
authors.forename: Steven H
authors.initials: SH
authors.lastname: Zeisel
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.forename: June M
authors.initials: JM
authors.lastname: Chan
mesh_terms: D000328:Adult; D000368:Aged; D001622:Betaine / Q000008:administration & dosage / Q000009:adverse effects; D002794:Choline / Q000008:administration & dosage / Q000009:adverse effects*; D015331:Cohort Studies; D004032:Diet / Q000009:adverse effects*; D018450:Disease Progression; D005500:Follow-Up Studies; D006282:Health Personnel; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010713:Phosphatidylcholines / Q000008:administration & dosage / Q000009:adverse effects; D010767:Phosphorylcholine / Q000008:administration & dosage / Q000009:adverse effects; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000401:mortality* / Q000503:physiopathology; D012306:Risk; D013109:Sphingomyelins / Q000008:administration & dosage / Q000009:adverse effects; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins; D010767:Phosphorylcholine; D001622:Betaine; D002794:Choline