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Updated: Sep 28, 2026

Quantitative Autonomic Testing
Published on: July 19, 2011
Cardiovascular autonomic nervous system tests: reference values in young people (15-19 years) and influence of age
Ingrid Tonhajzerová1, Kamil Javorka, Michal Javorka
1Department of Physiology, Jessenius Medical Faculty, Comenius University, Martin, Slovakia. tonhajzerova@ifmed.uniba.sk
Objective:
The aim of this study was to determine values of the deep breathing test (DB), orthostatic test (OT) and Valsalva manoeuvre (VM) parameters in young people and influence of age and gender.
Methods:
A total of 206 healthy subjects (100 girls, 106 boys) at the age of 15-19 years, BMI 21.3+/-2.3 (mean +/- SD) were examined by system Varia Pulse TF3.
Results:
Reference values of DB, OT, VM parameters are presented as arithmetic mean +/- SD and percentiles (P90, P75, P50, P25, P10). In the whole group HRrest was lower in 19-year-old group, in OT this difference was significant already in 18-year-old group compared with 15-year-old group. DB: I/E was significantly increased in 19-year-old group compared with 15-year-old group. HRrest was higher in girls compared with boys in the whole group. DB: I/E was significantly lower in girls compared with boys. OT: 30:15 and HRmax/HRrest were significantly decreased in girls compared with boys.
Conclusion:
Reference values of DB, OT, VM parameters were determined in young people at the age of 15-19 years. The most sensitive test for ascertainment of developmental changes was test of deep breathing. I/E was increased in the 19-year-old group compared with 15-year-old group indicating an increase of vagal activity. Girls had decreased some parameters of deep breathing and orthostatic test compared with boys in the same group (15-19 years).
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