Changes in the sweatspot test with ageing and relation to cardiovascular autonomic function

Area of Science:

• Gerontology
• Autonomic Neuroscience
• Clinical Physiology

Background:

• The sweatspot test measures local sweat response to acetylcholine, indicating autonomic dysfunction.
• Previous studies suggest its sensitivity in diabetic men and patients with chronic constipation.
• Its utility in the elderly, a population with high rates of autonomic dysfunction, remains unestablished.

Purpose of the Study:

• To evaluate the sweatspot test's diagnostic value in elderly individuals.
• To compare age-associated sweatspot responses with cardiovascular autonomic function.
• To assess differences between normotensive and hypertensive elderly subjects.

Main Methods:

• Compared sweatspot test results in elderly (n=35) and young (n=11) control groups.
• Included elderly normotensive (n=11) and untreated hypertensive (n=24) subjects.
• Correlated sweatspot scores with a battery of cardiovascular autonomic function tests.

Main Results:

• Elderly subjects had significantly lower sweatspot scores than young controls (1.9 vs. 12.0, p < 0.0001).
• No significant difference in sweatspot scores was found between elderly normotensive and hypertensive groups (1.6 vs. 2.4, p = 0.8).
• No correlation was observed between sweatspot scores and cardiovascular autonomic function tests.

Conclusions:

• The sweatspot test is grossly abnormal in all elderly subjects studied.
• Its results in the elderly do not correlate with cardiovascular autonomic function.
• The sweatspot test has very limited diagnostic value for autonomic dysfunction in the elderly population.