title: The relation of autonomic function to physical fitness in patients suffering from alcohol dependence.
abstract: BACKGROUND
  Reduced cardio-vascular health has been found in patients suffering from alcohol dependence. Low cardio-respiratory fitness is an independent predictor of cardio-vascular disease.
  
  
  METHODS
  We investigated physical fitness in 22 alcohol-dependent patients 10 days after acute alcohol withdrawal and compared results with matched controls. The standardized 6-min walk test (6 MWT) was used to analyze the relationship of autonomic dysfunction and physical fitness. Ventilatory indices and gas exchanges were assessed using a portable spiroergometric system while heart rate recordings were obtained separately. We calculated walking distance, indices of heart rate variability and efficiency parameters of heart rate and breathing. In addition, levels of exhaled carbon monoxide were measured in all participants to account for differences in smoking behaviour. Multivariate analyses of variance (MANOVA) were performed to investigate differences between patients and controls with regard to autonomic and efficiency parameters.
  
  
  RESULTS
  Patients walked a significantly shorter distance in comparison to healthy subjects during the 6 MWT. Significantly decreased heart rate variability was observed before and after the test in patients when compared to controls, while no such difference was observed during exercise. The efficiency parameters indicated significantly reduced efficiency in physiological regulation when the obtained parameters were normalized to the distance.
  
  
  CONCLUSIONS
  The 6 MWT is an easily applied instrument to measure physical fitness in alcohol dependent patients. It can also be used during exercise interventions. Reduced physical fitness, as observed in our study, might partly be caused by autonomic dysfunction, leading to less efficient regulation of physiological processes during exercise.
authors.affiliation: Pain & Autonomic Integrative Research (PAIR), Department of Psychiatry and Psychotherapy, University Hospital, Jena, Germany; Department of Sports Medicine and Health Promotion, Friedrich-Schiller-University, Jena, Germany.
authors.forename: Marco
authors.initials: M
authors.lastname: Herbsleb
authors.forename: Steffen
authors.initials: S
authors.lastname: Schulz
authors.forename: Stephanie
authors.initials: S
authors.lastname: Ostermann
authors.forename: Lars
authors.initials: L
authors.lastname: Donath
authors.forename: Daniela
authors.initials: D
authors.lastname: Eisenträger
authors.forename: Christian
authors.initials: C
authors.lastname: Puta
authors.forename: Andreas
authors.initials: A
authors.lastname: Voss
authors.forename: Holger W
authors.initials: HW
authors.lastname: Gabriel
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D001784:Blood Gas Analysis / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010809:Physical Fitness / Q000502:physiology* / Q000523:psychology; D015656:Respiratory Mechanics / Q000502:physiology*; D013375:Substance Withdrawal Syndrome / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D016138:Walking / Q000502:physiology* / Q000523:psychology; D055815:Young Adult
keywords: Alcohol dependence; Cardiac death; Cardio-vascular disease; Heart rate variability; Physical exercise