Abstract

Background
The standardized autonomic function test has become widely available. However, there are no reference data for this test for the Korean population. This study explored reference data for sudomotor and cardiovagal function tests for the Korean population.
Methods
The sweat volume by quantitative sudomotor axon reflex test, heart-rate response to deep breathing (HRdb), expiration:inspiration (E:I) ratio, and Valsalva ratio (VR) were measured in 297 healthy Korean volunteers aged from 20 to 69 years. Multivariate regression analysis was performed to evaluate the effects of age, sex, and body mass index on these variables. The 2.5th, 5th, 10th, 90th, 95th, and 97.5th percentile values were obtained for each investigation.
Results
The sweat volume was higher in males than in females. The HRdb and E:I ratio were negatively correlated with age, and were higher in males than in females. The VR was negatively correlated with age, but it was not correlated with sex.
Conclusions
This study has provided data on the reference ranges for sudomotor and cardiovagal function tests in healthy Korean adults.

• Key words: Autonomic nervous system; Reference range, Sweating; Parasympathetic nervous system