Arterial compliance changes in diabetic normotensive patients after angiotensin-converting enzyme inhibition therapy

Diabetes mellitus (DM) is known to cause increased arterial wall stiffness and increased cardiovascular risk, even in the absence of hypertension. This study was designed to investigate whether use of an angiotensin-converting enzyme (ACE) inhibitor may improve arterial stiffness in normotensive diabetics, using pulse wave velocity (PWV) as a surrogate marker.

We studied 42 patients (26 with type 2 DM, aged 56.5 +/- 9 years, 16 with type 1 DM, aged 41.5 +/- 11 years) by measuring PWV at baseline (compared to 15 age- and gender-matched normal subjects) and after 6 months of treatment with perindopril (4 mg/d).

At baseline, PWV was significantly higher in DM patients versus controls (13.09 +/- 2.59 v 9.5 +/- 1.6 m/sec, respectively, P < .001). After 6 months, PWV decreased significantly to 11.68 +/- 3.08 m/sec (P < .003) for the whole DM group. However, the results were driven by the change in the younger type 1 DM (from 12.59 +/- 1.59 to 10.35 +/- 2.21 m/sec, P < .001), whereas in the type 2 DM it was insignificant (from 13.37 +/- 3.0 to 12.42 +/- 3.28 m/sec). Blood pressure and other hemodynamic and biochemical parameters remained unchanged.

The results demonstrate that ACE inhibition can improve arterial elasticity and hence risk of cardiovascular complications even in normotensive diabetics. This short treatment was effective only in younger patients with type 1 diabetes, suggesting that early initiation of therapy before the onset of advanced structural alterations is likely to be more cardioprotective.