title: Caffeine increases aortic stiffness in hypertensive patients.
abstract: BACKGROUND
  Caffeine is the most widely used pharmacologic substance. Aortic stiffness is an important factor for cardiovascular system performance and a prognosticator of cardiovascular risk. We investigated the effect of caffeine on aortic stiffness in treated hypertensive patients.
  
  
  METHODS
  We studied the effect of caffeine (250 mg) in 12 treated hypertensive patients according to a randomized, placebo-controlled, double-blind, cross-over design during a 3-h period. Aortic stiffness was evaluated by carotid-femoral pulse wave velocity.
  
  
  RESULTS
  Systolic blood pressure (BP) and pulse pressure increased significantly throughout the study (by 12.3 and 7.4 mm Hg, P =.005 and P <.01, respectively), whereas diastolic BP did not change. Pulse wave velocity increased (by 0.57 m/sec, P <.05) denoting an increase in aortic stiffness. This effect of caffeine lasted throughout the study (3 h), peaking at 60 min and decreasing progressively thereafter.
  
  
  CONCLUSIONS
  These results demonstrate, for the first time, that caffeine exerts an acute unfavorable effect on aortic stiffness in treated hypertensive patients. This finding has important implications for the impact of caffeine consumption on cardiovascular risk in hypertension.
authors.affiliation: Medical Professorial Unit, St. Vincent's Hospital and Clinic, University of New South Wales, Sydney, Australia. cvlachop@otenet.gr
authors.forename: Charalambos
authors.initials: C
authors.lastname: Vlachopoulos
authors.forename: Kozo
authors.initials: K
authors.lastname: Hirata
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Stefanadis
authors.forename: Pavlos
authors.initials: P
authors.lastname: Toutouzas
authors.forename: Michael F
authors.initials: MF
authors.lastname: O'Rourke
mesh_terms: D001011:Aorta / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D001018:Aortic Diseases / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D001783:Blood Flow Velocity / Q000187:drug effects; D002110:Caffeine / Q000009:adverse effects*; D018592:Cross-Over Studies; D004548:Elasticity; D005260:Female; D006801:Humans; D006973:Hypertension / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects*; D010919:Placebos
chemical_list: D010726:Phosphodiesterase Inhibitors; D010919:Placebos; D002110:Caffeine