title: Relationship between low Ankle-Brachial Index and rapid renal function decline in patients with atrial fibrillation: a prospective multicentre cohort study.
abstract: OBJECTIVE
  To investigate the relationship between Ankle-Brachial Index (ABI) and renal function progression in patients with atrial fibrillation (AF).
  
  
  METHODS
  Observational prospective multicentre cohort study.
  
  
  METHODS
  Atherothrombosis Center of I Clinica Medica of 'Sapienza' University of Rome; Department of Medical and Surgical Sciences of University Magna Græcia of Catanzaro; Atrial Fibrillation Registry for Ankle-Brachial Index Prevalence Assessment-Collaborative Italian Study.
  
  
  METHODS
  897 AF patients on treatment with vitamin K antagonists.
  
  
  METHODS
  The relationship between basal ABI and renal function progression, assessed by the estimated Glomerular Filtration Rate (eGFR) calculated with the CKD-EPI formula at baseline and after 2 years of follow-up. The rapid decline in eGFR, defined as a decline in eGFR >5 mL/min/1.73 m(2)/year, and incident eGFR<60 mL/min/1.73 m(2) were primary and secondary end points, respectively.
  
  
  RESULTS
  Mean age was 71.8±9.0 years and 41.8% were women. Low ABI (ie, ≤0.90) was present in 194 (21.6%) patients. Baseline median eGFR was 72.7 mL/min/1.73 m(2), and 28.7% patients had an eGFR<60 mL/min/1.73 m(2). Annual decline of eGFR was -2.0 (IQR -7.4/-0.4) mL/min/1.73 m(2)/year, and 32.4% patients had a rapid decline in eGFR. Multivariable logistic regression analysis showed that ABI ≤0.90 (OR 1.516 (95% CI 1.075 to 2.139), p=0.018) and arterial hypertension (OR 1.830 95% CI 1.113 to 3.009, p=0.017) predicted a rapid eGFR decline, with an inverse association for angiotensin converting enzyme (ACE) inhibitors/angiotensin receptor blockers (OR 0.662 95% CI 0.464 to 0.944, p=0.023). Among the 639 patients with AF with eGFR >60 mL/min/1.73 m(2), 153 (23.9%) had a reduction of the eGFR <60 mL/min/1.73 m(2). ABI ≤0.90 was also an independent predictor for incident eGFR<60 mL/min/1.73 m(2) (HR 1.851, 95% CI 1.205 to 2.845, p=0.005).
  
  
  CONCLUSIONS
  In patients with AF, an ABI ≤0.90 is independently associated with a rapid decline in renal function and incident eGFR<60 mL/min/1.73 m(2). ABI measurement may help identify patients with AF at risk of renal function deterioration.
  
  
  BACKGROUND
  NCT01161251.
authors.affiliation: Department of Internal Medicine and Medical Specialties, I Clinica Medica, Atherothrombosis Center, Sapienza University of Rome, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Violi
authors.affiliation: Department of Internal Medicine and Medical Specialties, I Clinica Medica, Atherothrombosis Center, Sapienza University of Rome, Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Pastori
authors.affiliation: Department of Medical and Surgical Sciences, University Magna Græcia of Catanzaro, Catanzaro, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Perticone
authors.affiliation: Division of Cardiology, University of Colorado School of Medicine and CPC Clinical Research, Aurora, Colorado, USA.
authors.forename: William R
authors.initials: WR
authors.lastname: Hiatt
authors.affiliation: Department of Medical and Surgical Sciences, University Magna Græcia of Catanzaro, Catanzaro, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Sciacqua
authors.affiliation: Department of Internal Medicine and Medical Specialties, I Clinica Medica, Atherothrombosis Center, Sapienza University of Rome, Rome, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Basili
authors.affiliation: Department of Internal Medicine and Medical Specialties, I Clinica Medica, Atherothrombosis Center, Sapienza University of Rome, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Proietti
authors.affiliation: First Department of Internal Medicine, Fondazione IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy.
authors.forename: Gino R
authors.initials: GR
authors.lastname: Corazza
authors.affiliation: Centre for Cardiovascular Sciences, University of Birmingham, Birmingham, UK.
authors.forename: Gregory Y H
authors.initials: GY
authors.lastname: Lip
authors.affiliation: Department of Internal Medicine and Medical Specialties, I Clinica Medica, Atherothrombosis Center, Sapienza University of Rome, Rome, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Pignatelli
mesh_terms: D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D055109:Ankle Brachial Index; D001281:Atrial Fibrillation / Q000150:complications / Q000503:physiopathology*; D001794:Blood Pressure; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology; D007558:Italy; D007668:Kidney / Q000503:physiopathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000209:etiology / Q000503:physiopathology*; D012307:Risk Factors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors