title: Association of coffee and caffeine intake with the risk of Parkinson disease.
abstract: BACKGROUND
  The projected expansion in the next several decades of the elderly population at highest risk for Parkinson disease (PD) makes identification of factors that promote or prevent the disease an important goal.
  
  
  OBJECTIVE
  To explore the association of coffee and dietary caffeine intake with risk of PD.
  
  
  METHODS
  Data were analyzed from 30 years of follow-up of 8004 Japanese-American men (aged 45-68 years) enrolled in the prospective longitudinal Honolulu Heart Program between 1965 and 1968.
  
  
  METHODS
  Incident PD, by amount of coffee intake (measured at study enrollment and 6-year follow-up) and by total dietary caffeine intake (measured at enrollment).
  
  
  RESULTS
  During follow-up, 102 men were identified as having PD. Age-adjusted incidence of PD declined consistently with increased amounts of coffee intake, from 10.4 per 10,000 person-years in men who drank no coffee to 1.9 per 10,000 person-years in men who drank at least 28 oz/d (P<.001 for trend). Similar relationships were observed with total caffeine intake (P<.001 for trend) and caffeine from non-coffee sources (P=.03 for trend). Consumption of increasing amounts of coffee was also associated with lower risk of PD in men who were never, past, and current smokers at baseline (P=.049, P=.22, and P=.02, respectively, for trend). Other nutrients in coffee, including niacin, were unrelated to PD incidence. The relationship between caffeine and PD was unaltered by intake of milk and sugar.
  
  
  CONCLUSIONS
  Our findings indicate that higher coffee and caffeine intake is associated with a significantly lower incidence of PD. This effect appears to be independent of smoking. The data suggest that the mechanism is related to caffeine intake and not to other nutrients contained in coffee. JAMA. 2000;283:2674-2679.
authors.affiliation: Department of Veterans Affairs, Honolulu (151), PO Box 50188, Honolulu, HI 96850, USA. ross@phri.hawaii-health.com
authors.forename: G W
authors.initials: GW
authors.lastname: Ross
authors.forename: R D
authors.initials: RD
authors.lastname: Abbott
authors.forename: H
authors.initials: H
authors.lastname: Petrovitch
authors.forename: D M
authors.initials: DM
authors.lastname: Morens
authors.forename: A
authors.initials: A
authors.lastname: Grandinetti
authors.forename: K H
authors.initials: KH
authors.lastname: Tung
authors.forename: C M
authors.initials: CM
authors.lastname: Tanner
authors.forename: K H
authors.initials: KH
authors.lastname: Masaki
authors.forename: P L
authors.initials: PL
authors.lastname: Blanchette
authors.forename: J D
authors.initials: JD
authors.lastname: Curb
authors.forename: J S
authors.initials: JS
authors.lastname: Popper
authors.forename: L R
authors.initials: LR
authors.lastname: White
mesh_terms: D000368:Aged; D002110:Caffeine; D003069:Coffee; D004034:Diet Surveys; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000453:epidemiology*; D012044:Regression Analysis; D012307:Risk Factors
chemical_list: D003069:Coffee; D002110:Caffeine