Skin vasomotor reflex responses in two contrasting groups of autonomic failure - Multiple system atrophy and pure autonomic failure

Background & Aim A variety of stimuli such as deep inspiration, isometric exercise and mental arithmetic, result in a transient vasoconstriction,mediated by sympathetic efferent nerves, in the skin of the fingers and toes of healthy controls (Skin Vasomotor Reflex: SkVR). Multiple system atrophy (MSA) and pure autonomic failure (PAF) provide contrasting models of autonomic failure. In MSA the lesion is central and preganglionic, whilst in PAF the lesion site is peripheral and postganglionic. We evaluated the SkVR in response to various stimuli in MSA and PAF, to determine differences in skin vasomotor involvement between these two patient groups.