Carotid intima-media thickness and cerebrovascular reactivity in long-term type 1 diabetes mellitus.

PURPOSE

Diabetes mellitus (DM) is one of the leading risk factors for cerebrovascular diseases. Both macro- and microvascular damage may occur. The aim of the present work was to assess intima-media thickness as well as cerebral vasoreactivity in patients suffering from type 1 diabetes mellitus (IDDM).

METHODS

Intima-media thickness and resting middle cerebral artery blood flow velocity was measured in 33 IDDM patients and 31 healthy controls. After baseline investigations, 30 seconds of breath holding (BH) and 60 seconds of voluntary hyperventilation (HV) were performed by the subjects. Transcranial Doppler measurements were performed in each case after vasodilatory (BH) and vasoconstrictor (HV) stimuli. Cerebrovascular reactivity was expressed as the percentage of change of the middle cerebral mean blood flow velocity after BH or HV.

RESULTS

IDDM patients showed a significantly larger intima-media thickness (0.1 +/- 0.02 mm) than healthy controls (0.06 +/- 0.006 mm, p < 0.001). Cerebrovascular reactivity after BH was less intensive in diabetic patients (19.3 +/- 16.1%) than that of the control subjects (38.7 +/- 22.8%, p < 0.01). Similarly, HV induced a less-pronounced decrease of cerebral blood flow velocity in diabetic subjects (-30.1 +/- 13.2%) than in nondiabetics (-37.6 +/- 17.0%, p < 0.05).

CONCLUSION

Our results refer to early macro- and microangiopathic involvement of the cerebral vessels, which develop in parallel with angiopathies of the other organs, such as nephropathy and retinopathy. Further prospective studies are needed to clarify the role of these macro- and microangiopathic changes in the development of cerebrovascular complications in patients suffering from DM.