Decreased cutaneous vasodilatation to isometric handgrip exercise in Alzheimer's disease.

BACKGROUND

Cutaneous active vasodilatation is a cholinergic nerve mediated function of the sympathetic nervous system and the disturbed function of cholinergic neurotransmission is known as a prominent feature of Alzheimer's disease (AD).

METHODS

To assess this relationship, skin blood flow (SkBF) and other haemodynamic parameters were determined by a simple vasodilatory test, isometric handgrip exercise (IHG), in 22 late-onset sporadic type AD and 20 aged control persons (AC).

RESULTS

Significantly higher cutaneous vascular resistance and decreased SkBF were found after the stimulus in the AD group. A smaller reduction (p < 0.03) of R wave intervals on the electrocardiogram was observed in the AD group compared to the AC one. After IHG, change in systolic blood pressure was less in the AD (p < 0.01) than in the AC group.

CONCLUSION

Our results suggest that autonomic dysfunction affecting active vasodilator sympathetic, as well as parasympathetic functions is present in AD.