title: ABI derived from the highest and lowest ankle pressure. What is the difference?
abstract: OBJECTIVE
  Different modes of ankle-brachial -index (ABI) calculation lead to different information. We looked for the peripheral arterial disease (PAD) prevalence estimated from ABI-high and ABI-low and analysed the effect of age and classical risk factors.
  
  
  METHODS
  Based on the Arteriomobil Project data, ABI was calculated considering the lowest of the four ankle artery pressures (ABI-low) or the higher ankle artery pressure of each leg (ABI-high), respectively. ABI <0.9 were defined to prove PAD.
  
  
  RESULTS
  Prevalence of PAD estimated using ABI-low was much higher than those using ABI- high (15.7% vs. 8.0%). Thus 8% of men and 7.5% of women suspected for PAD were not detected if prevalence rates are based on ABI-high alone. Estimating PAD prevalence only by measuring posterior tibial artery (ATP) pressure, prevalence rates were lowest with 2.4% for the left and 2.7% for the right ATP. Estimating PAD prevalence only by measuring anterior tibial artery pressure, prevalence rates were slightly higher, but still low. ABI-high systematically shows lower prevalence rates compared to ABI-low without divergence of the prevalence rates with increasing age. This parallelism of the curves remained unchanged when prevalence rates were separated for self-reported risk-factors; smoking, hypertension, hypercholesterolemia and diabetes.
  
  
  CONCLUSIONS
  The presented analysis of the Arteriomobil Project data support the hypothesis that the differences in prevalence rates estimated from ABI-high and ABI-low are mainly determined by anatomic variations of the plantar arch. Additional angiographic controlled studies are necessary to prove this hypothesis.
authors.affiliation: Department of Angiology, HELIOS Klinikum Krefeld, Lutherplatz 40, Krefeld, Germany. knut.kroeger@helios-kliniken.de
authors.forename: K
authors.initials: K
authors.lastname: Kröger
authors.forename: E
authors.initials: E
authors.lastname: Bock
authors.forename: T
authors.initials: T
authors.lastname: Hohenberger
authors.forename: Th
authors.initials: T
authors.lastname: Moysidis
authors.forename: F
authors.initials: F
authors.lastname: Santosa
authors.forename: M
authors.initials: M
authors.lastname: Pfeifer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000098:blood supply*; D055109:Ankle Brachial Index / Q000379:methods*; D001794:Blood Pressure; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D058729:Peripheral Arterial Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult