title: Heart rate variability in patients with essential hyperhidrosis: dynamic influence of sympathetic and parasympathetic maneuvers.
abstract: BACKGROUND
  Essential hyperhidrosis has been associated with an increased activity of the sympathetic system. In this study, we investigated cardiac autonomic function in patients with essential hyperhidrosis and healthy controls by time and frequency domain analysis of heart rate variability (HRV).
  
  
  METHODS
  In this study, 12 subjects with essential hyperhidrosis and 20 healthy subjects were included. Time and frequency domain parameters of HRV were obtained from all of the participants after a 15-minute resting period in supine position, during controlled respiration (CR) and handgrip exercise (HGE) in sitting position over 5-minute periods in each stage.
  
  
  RESULTS
  Baseline values of HRV parameters including RR interval, SDNN and root mean square of successive R-R interval differences, low frequency (LF), high frequency (HF), normalized unit of high frequency (HFnu), normalized unit of low frequency (LFnu), and LF/HF ratio were identical in two groups. During CR, no difference was detected between the two groups with respect to HRV parameters. However, the expected increase in mean heart rate (mean R-R interval) did not occur in hyperhidrotic group, whereas it did occur in the control group (Friedman's P = 0.000). Handgrip exercise induced significant decrease in mean R-R interval in both groups and no difference was detected between the two groups with respect to the other HRV parameters. When repeated measurements were compared with two-way ANOVA, there was statistically significant difference only regarding mean heart rate in two groups (F = 6.5; P = 0.01).
  
  
  CONCLUSIONS
  Our overall findings suggest that essential hyperhidrosis is a complex autonomic dysfunction rather than sympathetic overactivity, and parasympathetic system seems to be involved in pathogenesis of this disorder.
authors.affiliation: Department of Cardiology, Ege Saglik Hospital, Yzmir, Turkey.
authors.forename: Dayimi
authors.initials: D
authors.lastname: Kaya
authors.forename: Semsettin
authors.initials: S
authors.lastname: Karaca
authors.forename: Irfan
authors.initials: I
authors.lastname: Barutcu
authors.forename: Ali Metin
authors.initials: AM
authors.lastname: Esen
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kulac
authors.forename: Ozlem
authors.initials: O
authors.lastname: Esen
mesh_terms: D000704:Analysis of Variance; D016022:Case-Control Studies; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D006945:Hyperhidrosis / Q000503:physiopathology*; D008297:Male; D010275:Parasympathetic Nervous System / Q000503:physiopathology*; D012146:Rest; D018709:Statistics, Nonparametric; D013564:Sympathetic Nervous System / Q000503:physiopathology*