title: Sympathetic skin response and heart rate variability in patients with Huntington disease.
abstract: OBJECTIVE
  To examine the autonomic nervous system functions in patients with Huntington disease.
  
  
  BACKGROUND
  Although patients with Huntington disease frequently experience vegetative symptoms, it is not clear if there is dysfunction of the autonomic nervous system.
  
  
  METHODS
  Sympathetic skin response (SSR) latency and amplitude from both palms and soles and R-R (heart rate) interval variation (RRIV) at rest and during the Valsalva maneuver were examined in 22 patients and 21 age-matched controls. Unified Huntington's Disease Rating Scale scores were determined in all the patients.
  
  
  RESULTS
  Our data are reported as means +/- SEMs. The SSR latencies in patients (mean palm latency, 1835.8+/-110.7 milliseconds; mean sole latency, 2625.3+/-226.9 milliseconds) were prolonged compared with controls (mean palm latency, 1359.5+/-28 milliseconds [P<.01]); mean sole latency, 2038.1+/-44.9 milliseconds [P<.01]) and amplitudes in patients (mean amplitude, 1063.1+/-237.7 microV) were smaller compared with controls (mean amplitude, 1846.3+/-251.2 microV [P<.05]). The RRIV in patients both at rest (mean RRIV in patients, 3.7%+/-0.4% vs. controls, 9.7%+/-0.6% [P<.01]) and during the Valsalva maneuver (mean RRIV in patients, 6.3%+/-1.6% vs. controls, 14.5%+/-1.2% [P<.01]) was lower compared with controls. Furthermore, the prolonged SSR latencies, smaller amplitudes, and lower RRIV in patients compared with controls closely correlated with the various components of the Unified Huntington's Disease Rating Scale scores (total behavior score and SSR latency, R = 0.6 [P<.01]; total behavior score and SSR amplitude, R = -0.5 [P<.05]; total behavior score and RRIV, R = -0.4 [P<.05]; verbal fluency and SSR latency, R = -0.5 [P<.05]; verbal fluency and SSR amplitude, R = 0.5 [P<.05], verbal fluency and RRIV, R = 0.5 [P<.05]; total functional capacity and SSR latency, R = -0.6 [P<.01]; total functional capacity and SSR amplitude, R = 0.5 [P<.05]).
  
  
  CONCLUSIONS
  These results suggest that there is autonomic nervous system dysfunction in patients with Huntington disease.
authors.affiliation: Department of Neurology, University of Miami, Fla. 33136, USA. ksharma@med.miami.edu
authors.forename: K R
authors.initials: KR
authors.lastname: Sharma
authors.forename: J G
authors.initials: JG
authors.lastname: Romano
authors.forename: D R
authors.initials: DR
authors.lastname: Ayyar
authors.forename: F T
authors.initials: FT
authors.lastname: Rotta
authors.forename: A
authors.initials: A
authors.lastname: Facca
authors.forename: J
authors.initials: J
authors.lastname: Sanchez-Ramos
mesh_terms: D000328:Adult; D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D005260:Female; D005712:Galvanic Skin Response; D006339:Heart Rate; D006801:Humans; D006816:Huntington Disease / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction; D010543:Peroneal Nerve / Q000502:physiology; D011930:Reaction Time; D013497:Sural Nerve / Q000502:physiology; D014636:Valsalva Maneuver