title: Symptoms of chronic arterial insufficiency correlate with absolute ankle pressure better than with ankle: brachial index.
abstract: BACKGROUND
  Doppler-based measurement of the ankle: brachial index (ABI) has long been regarded as the standard by which to objectively quantify the degree of lower extremity arterial occlusive disease, but this method fails to account for the contribution of systemic blood pressure to actual limb perfusion. We hypothesized that the absolute blood pressure would be a better predictor of the severity of symptoms of chronic occlusive disease than the ABI.
  
  
  METHODS
  retrospective comparative study.
  
  
  METHODS
  university inpatient/outpatient vascular laboratory.
  
  
  METHODS
  1396 evaluable patients out of 2436 total consecutive patients referred with suspected lower extremity arterial occlusive disease.
  
  
  METHODS
  comparison of absolute ankle and digital pressures and ABI according to severity of symptoms of chronic lower extremity ischemia using three-way analysis of variance (ANOVA), likelihood ratios, and receiver operator characteristic (ROC) curves.
  
  
  RESULTS
  The symptoms of tissue ulcer/gangrene, rest pain, and gangrene were characterized by differences in absolute pressures in the great toe (47 +/- 42 mmHg vs 55 +/- 40 mmHg vs 62 +/- 33 mmHg [mean +/- SD], F = 19.05, p < 0.001) and ankle (92 +/- 53 mmHg vs 98 +/- 44 mmHg vs 106 +/- 37 mmHg, F = 12.91, p < 0.001), but not by the ABI (0.71 +/- 0.33 vs 0.68 +/- 0.34 vs 0.71 +/- 0.28, F = 1.24, p > 0.05). ROC curves confirmed absolute digital pressure (area under curve [AUC] = 0.628) and absolute ankle pressure (AUC = 0.607) to be superior to ABI (AUC = 0.572).
  
  
  CONCLUSIONS
  The severity of symptoms for peripheral vascular disease correlate better with absolute pressure measurement than with ABI.
authors.affiliation: Department of Surgery, Medical University of South Carolina, Charleston, USA. brothete@muse.edu
authors.forename: T E
authors.initials: TE
authors.lastname: Brothers
authors.forename: R
authors.initials: R
authors.lastname: Esteban
authors.forename: J G
authors.initials: JG
authors.lastname: Robison
authors.forename: B M
authors.initials: BM
authors.lastname: Elliott
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000842:Ankle; D001157:Arterial Occlusive Diseases / Q000175:diagnosis* / Q000503:physiopathology; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D001916:Brachial Artery; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D012720:Severity of Illness Index