Cerebral and skin microcirculatory dysfunction in type 1 diabetes

Introduction
An increase in cerebral pulsatility index (PI), measured by transcranial Doppler, reflects the presence of cerebral microangiopathy. A decrease in distance between skin capillaries (DISTANCE) and an increase in the ratio between the area of capillaries and total area of examined skin (COVERAGE), revealed by capillaroscopy, reflects skin microangiopathy. However, little is known about the association between the cerebral and skin microvasculature function in patients at risk of microcirculatory dysfunction.

Aim
To assess PI of the middle cerebral artery by transcranial Doppler and the DISTANCE and COVERAGE of the nailfold capillaries by quantitative capillaroscopy in patients with type 1 diabetes and control subjects without diabetes, and to investigate relationships between these parameters.

Material and methods
The study group consisted of 51 patients with type 1 diabetes (median age: 37.5 years) and 23 volunteers free from chronic diseases (median age: 37.9 years).

Results
Median PI was higher in patients than in control subjects (0.82 vs. 0.75; p < 0.01). Median DISTANCE was lower in patients than in control subjects (220.9 µm vs. 239.7 µm; p = 0.03), while median COVERAGE was higher in patients than in control subjects (20.4% vs. 18.3%; p = 0.01). No correlations between PI and DISTANCE or COVERAGE were found, but PI was correlated with patients’ age and diabetes duration.

Conclusions
In spite of simultaneous presence of cerebral and skin microangiopathy, we found no association between cerebral and skin microvasculature dysfunction. This seems to indicate independent progression of microcirculatory injury in cerebral and peripheral vascular beds.