title: Sympathetic function test of vasoconstrictor changes in foot arteries in diabetic patients.
abstract: OBJECTIVE
  We studied the relationship between vasoconstrictor changes in foot arteries (pedal, metatarsal, and digital arteries) and autonomic neuropathy in diabetic patients to estimate the degrees of sympathetic dysfunction.
  
  
  METHODS
  Sixty-two patients and nineteen age-matched control subjects were studied. The resistance index (RI) and pulsatility index (PI) were measured as vascular hemodynamic parameters using Doppler sonography, and the increases in these hemodynamic parameters (%RI and %PI) from rest to a deep breath were measured as indexes of the degrees of sympathetic vasoconstrictor function. Cardiovascular autonomic function tests (AFTs) were performed and the score was compared to %RI and %PI values obtained.
  
  
  RESULTS
  Of the 62 diabetic patients, 51 had various degrees of autonomic neuropathy. Both %RI and %PI in the diabetic patients were significantly less than those in the control subjects for all foot arteries tested (all P < 0.001). There were strongly inverse correlations between the %RI and %PI of foot arteries and the AFT score (r = -0.556 to -0.846, P < 0.0001). The %RI of the digital artery was the most strongly correlated with AFT score (r = -0.846, P < 0.0001) among foot arteries tested. The abnormality of sympathetic vasoconstriction was detectable in the majority of the diabetic patients with the early phase of autonomic neuropathy (%RI: 89.5%; %PI: 94.5%).
  
  
  CONCLUSIONS
  We conclude that the %RI of the digital artery is a useful and reliable sympathetic function test of early phase in diabetic patients.
authors.affiliation: Second Department of Internal Medicine, Osaka City University Medical School, Osaka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: Y
authors.initials: Y
authors.lastname: Nishizawa
authors.forename: M
authors.initials: M
authors.lastname: Emoto
authors.forename: T
authors.initials: T
authors.lastname: Kawagishi
authors.forename: N
authors.initials: N
authors.lastname: Matsumoto
authors.forename: E
authors.initials: E
authors.lastname: Ishimura
authors.forename: M
authors.initials: M
authors.lastname: Inaba
authors.forename: Y
authors.initials: Y
authors.lastname: Okuno
authors.forename: H
authors.initials: H
authors.lastname: Shimada
authors.forename: H
authors.initials: H
authors.lastname: Morii
mesh_terms: D000328:Adult; D001158:Arteries / Q000000981:diagnostic imaging*; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D005528:Foot / Q000098:blood supply*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D014034:Toes / Q000098:blood supply; D018616:Ultrasonography, Doppler, Duplex; D014655:Vascular Resistance