Diabetes Care, Vol 21, Issue 9 1495-1501, Copyright © 1998 by American Diabetes Association
Sympathetic function test of vasoconstrictor changes in foot arteries in diabetic patients
T Takahashi, Y Nishizawa, M Emoto, T Kawagishi, N Matsumoto, E Ishimura, M Inaba, Y Okuno, H Shimada and H Morii
Second Department of Internal Medicine, Osaka City University Medical School, Osaka, Japan.
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. RESEARCH DESIGN AND 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.