Aims/hypothesis. Type I (insulin-dependent) diabetes mellitus is accompanie
d by reduced arterial distensibility and increased arterial wall thickness
even in normotensive subjects with no micro-macrovascular complications. It
is not known whether, and how fast, these subclinical markers of vascular
damage develop over time.
Methods. We measured arterial wall distensibility in radial, common carotid
artery and abdominal aorta in 60 normotensive patients (aged 35.0 +/- 1.2
years, means +/- SE) with Type I diabetes with no microvascular or macrovas
cular complications and in 20 healthy control subjects matched for age. Art
erial distensibility was determined by continuous measurements of arterial
diameter through echotracking techniques and by using either the Langewoute
rs (radial artery) or the Reneman formula (carotid artery and aorta). The s
ame echotracking techniques allowed us to ascertain the radial and carotid
artery wall thickness. Data were collected before and after 23 +/- 1 months
.
Results. In the first study, carotid artery distensibility was similar but
radial artey and aortic distensibility was less (p < 0.01) in patients with
diabetes than in control subjects (-39% and 25% respectively). This was ac
companied by an increase (p < 0.01) in both radial (42%) and carotid artery
wall thickness (46%). After 23 +/- 1 months diabetic subjects showed a fur
ther reduction in arterial distensibility (radial-12%, p < 0.05; carotid-8%
, NS; aorta-20% p < 0.05) and an increase in arterial wall thickness (radia
l + 15%; carotid 14%, p < 0.05). No change in distensibility and wall thick
ness values occurred in control subjects.
Conclusion/interpretation. The early reduction in arterial distensibility a
nd increase in arterial wall thickness characterizing uncomplicated normote
nsive Type I diabetes patients shows a measurable worsening over the short
term.