title: Ankle blood pressure and dementia:  a prospective follow-up study.
abstract: OBJECTIVE
  Ankle blood pressure may be a useful indicator of arterial stiffness. The main aim of the present study was to examine the relationship of ankle blood pressure measured in midlife with the risk of dementia with advancing age. A secondary aim was to examine the relationship of physical exercise capacity in midlife with the risk of dementia.
  
  
  METHODS
  This prospective follow-up study was carried out on individuals (mean age 50 years, 66% men) referred to a symptom-limited exercise test between August 1989 and December 1995. The cohort of 3859 individuals free of dementia and vascular disease at baseline was followed for 18 years. The significance of ankle blood pressure as a predictor of incident dementia was analyzed using Cox proportional hazard models, controlling for several confounders including brachial systolic blood pressure.
  
  
  RESULTS
  Clinically incident dementia was observed in 123 of the 3859 participants during the mean follow-up period of 18 years. Significant associations were found between the elevated ankle blood pressure at baseline and clinically incident dementia during the follow-up. In individuals with normal resting and exercise brachial blood pressure but elevated ankle blood pressure, the hazard ratio was 1.58 (95% confidence interval 1.04-2.40, P=0.03, adjusted for age and sex). However, cardiovascular fitness, measured as metabolic equivalents at baseline, was inversely associated with dementia.
  
  
  CONCLUSIONS
  These results suggest that ankle blood pressure has an independent value as a marker of arterial stiffness or subclinical atherosclerosis and a risk of future dementia.
authors.affiliation: Department of Clinical Physiology, Deaconess Institute, National Institute for Health and Welfare (THL), Helsinki, Finland. heikki.hietanen@fimnet.fi
authors.forename: Heikki
authors.initials: H
authors.lastname: Hietanen
authors.forename: Arto
authors.initials: A
authors.lastname: Pietilä
authors.forename: Mika
authors.initials: M
authors.lastname: Kähönen
authors.forename: Veikko
authors.initials: V
authors.lastname: Salomaa
mesh_terms: D000368:Aged; D000375:Aging; D055109:Ankle Brachial Index; D015415:Biomarkers; D003704:Dementia / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D059289:Vascular Stiffness
chemical_list: D015415:Biomarkers