title: Usual blood pressure, atrial fibrillation and vascular risk: evidence from 4.3 million adults.
abstract: Although elevated blood pressure is associated with an increased risk of atrial fibrillation (AF), it is unclear if this association varies by individual characteristics. Furthermore, the associations between AF and a range of different vascular events are yet to be reliably quantified.
  
  
  
  Using linked electronic health records, we examined the time to first diagnosis of AF and time to first diagnosis of nine vascular events in a cohort of 4.3 million adults, aged 30 to 90 years, in the UK.
  
  
  
  : A 20-mmHg higher usual systolic blood pressure was associated with a higher risk of AF [hazard ratio (HR) 1.21, 95% confidence interval (CI) 1.19, 1.22]. The strength of the association declined with increasing age, from an HR of 1.91 (CI 1.75, 2.09) at age 30-40 to an HR of 1.01 (CI 0.97, 1.04) at age 80-90 years. AF without antithrombotic use at baseline was associated with a greater risk of any vascular event than AF with antithrombotic usage ( P interaction < 0.0001). AF without baseline antithrombotic usage was associated with an increased risk of ischaemic heart disease (HR 2.52, CI 2.23, 2.84), heart failure (HR 3.80, CI 3.50, 4.12), ischaemic stroke (HR 2.72, CI 2.19, 3.38), unspecified stroke (HR 2.59, CI 2.25, 2.99), haemorrhagic stroke, chronic kidney disease, peripheral arterial disease and vascular dementia, but not aortic aneurysm.
  
  
  
  The association between elevated blood pressure and AF attenuates with increasing age. AF without antithrombotic usage is associated with an increased risk of eight vascular events.
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.
authors.forename: Connor A
authors.initials: CA
authors.lastname: Emdin
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.|Cardiovascular Research Group, Institute of Cardiovascular Sciences, University of Manchester, Manchester, NH, USA.
authors.forename: Simon G
authors.initials: SG
authors.lastname: Anderson
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Salimi-Khorshidi
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.|George Institute for Global Health, University of Sydney, Sydney, NSW, Australia.|Department of Epidemiology, Johns Hopkins University, Baltimore,MD, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Woodward
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.|George Institute for Global Health, University of Sydney, Sydney, NSW, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: MacMahon
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.
authors.forename: Terrence
authors.initials: T
authors.lastname: Dwyer
authors.affiliation: George Institute for Global Health, University of Oxford, Oxford, UK.|Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
authors.forename: Kazem
authors.initials: K
authors.lastname: Rahimi
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications* / Q000453:epidemiology*; D001794:Blood Pressure; D001795:Blood Pressure Determination; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology; D014652:Vascular Diseases / Q000453:epidemiology*
keywords: Atrial fibrillation; blood pressure; cardiovascular disease; epidemiology