Vasopressor responses in autosomal dominant cerebellar ataxia.

Thirteen patients with autosomal dominant cerebellar ataxia were investigated for autonomic functions using standard tests. Patients showed no significant reduction in parasympathetic responses as measured by heart rate response to slow breathing and Valsalva manoeuvre. Measurement of blood pressure response to isometric exercise, cold exposure and 70 degrees head-up tilt showed a significant decrease in sympathetic pressor response.