title: Coffee and caffeine consumption and the risk of hypertension in postmenopausal women.
abstract: BACKGROUND
  The associations of coffee and caffeine intakes with the risk of incident hypertension remain controversial.
  
  
  OBJECTIVE
  We sought to assess longitudinal relations of caffeinated coffee, decaffeinated coffee, and total caffeine intakes with mean blood pressure and incident hypertension in postmenopausal women in the Women's Health Initiative Observational Study.
  
  
  METHODS
  In a large prospective study, type and amount of coffee and total caffeine intakes were assessed by using self-reported questionnaires. Hypertension status was ascertained by using measured blood pressure and self-reported drug-treated hypertension. The mean intakes of caffeinated coffee, decaffeinated coffee, and caffeine were 2-3 cups/d, 1 cup/d, and 196 mg/d, respectively. Using multivariable linear regression, we examined the associations of baseline intakes of caffeinated coffee, decaffeinated coffee, and caffeine with measured systolic and diastolic blood pressures at annual visit 3 in 29,985 postmenopausal women who were not hypertensive at baseline. We used Cox proportional hazards models to estimate HRs and their 95% CIs for time to incident hypertension.
  
  
  RESULTS
  During 112,935 person-years of follow-up, 5566 cases of incident hypertension were reported. Neither caffeinated coffee nor caffeine intake was associated with mean systolic or diastolic blood pressure, but decaffeinated coffee intake was associated with a small but clinically irrelevant decrease in mean diastolic blood pressure. Decaffeinated coffee intake was not associated with mean systolic blood pressure. Intakes of caffeinated coffee, decaffeinated coffee, and caffeine were not associated with the risk of incident hypertension (P-trend > 0.05 for all).
  
  
  CONCLUSIONS
  In summary, these findings suggest that caffeinated coffee, decaffeinated coffee, and caffeine are not risk factors for hypertension in postmenopausal women.
authors.affiliation: Divisions of Nephrology and rheej@stanford.edu.
authors.forename: Jinnie J
authors.initials: JJ
authors.lastname: Rhee
authors.affiliation: Biomedical Informatics Research, Department of Medicine and.
authors.forename: FeiFei
authors.initials: F
authors.lastname: Qin
authors.affiliation: Biomedical Informatics Research, Department of Medicine and.
authors.forename: Haley K
authors.initials: HK
authors.lastname: Hedlin
authors.affiliation: Divisions of Nephrology and.
authors.forename: Tara I
authors.initials: TI
authors.lastname: Chang
authors.affiliation: RAND Corporation, Santa Monica, CA;
authors.forename: Chloe E
authors.initials: CE
authors.lastname: Bird
authors.affiliation: Faculty of Health Sciences and Social Welfare, University of Haifa, Haifa, Israel;
authors.forename: Oleg
authors.initials: O
authors.lastname: Zaslavsky
authors.affiliation: Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA; and.
authors.forename: JoAnn E
authors.initials: JE
authors.lastname: Manson
authors.affiliation: Stanford Prevention Research Center, Stanford University School of Medicine, Palo Alto, CA;
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.affiliation: Selzman Institute for Kidney Health, Section of Nephrology, Department of Medicine, Baylor College of Medicine, Houston, TX.
authors.forename: Wolfgang C
authors.initials: WC
authors.lastname: Winkelmayer
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D002110:Caffeine / Q000009:adverse effects / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000009:adverse effects / Q000494:pharmacology; D003069:Coffee / Q000009:adverse effects / Q000737:chemistry; D004326:Drinking; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology*; D015994:Incidence; D008137:Longitudinal Studies; D008875:Middle Aged; D017698:Postmenopause; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D000697:Central Nervous System Stimulants; D003069:Coffee; D002110:Caffeine
keywords: blood pressure; caffeinated coffee; caffeine; decaffeinated coffee; hypertension