title: Assessment of heart rate response to exercise and recovery during treadmill testing in arsenic-exposed workers.
abstract: BACKGROUND
  Arsenic exposure is associated with various cardiovascular diseases. The aim of the present study was to assess cardiac autonomic function via heart rate response to exercise and recovery period of treadmill testing in arsenic-exposed workers.
  
  
  METHODS
  Sixty-five (65) occupationally arsenic-exposed workers and 35 healthy controls were enrolled. Blood and urinary arsenic levels were analyzed and symptom limited maximal treadmill exercise test were performed. Chronotropic response to exercise including age-predicted maximal heart rate (APMHR), heart rate reserve (HRreserve), age-predicted HRreserve(APHRreserve) and adjusted HRreserveand 1st-, 2nd-and 3rd-min heart rate recovery (HRR) indices were calculated.
  
  
  RESULTS
  Baseline clinical and echocardiographic parameters, exercise test duration, resting and maximal heart rate, peak exercise capacity, HRreserve, APMHR, APHRreserve, and adjusted HRreservewere found to be similar between groups. HRR1(22.0 ± 4.3 vs. 24.3 ± 3.1 bpm, p = .003) and HRR2(43.2 ± 6.2 vs. 46.7 ± 6.4 bpm, p = .012) were significantly lower in arsenic-exposed workers compared to controls. Blood and urinary arsenic levels negatively correlated with HRR1(r = -.477, p < .001 and r = -.438, p < .001, respectively) and HRR2(r = -.507, p < .001 and r = -.412, p < .001 respectively).
  
  
  CONCLUSIONS
  Arsenic-exposed workers had lower HRR indices than normal subjects but chronotropic response were similar. Cardiac autonomic dysregulation may be one of the cardiovascular consequences of arsenic exposure.
authors.affiliation: Department of Cardiology, Occupational Diseases Hospital, Ankara, Turkey.
authors.forename: Ugur Nadir
authors.identifier: http://orcid.org/0000-0001-9146-8765
authors.initials: UN
authors.lastname: Karakulak
authors.affiliation: Department of Clinical Toxicology, Occupational Diseases Hospital, Ankara, Turkey.
authors.forename: Meside
authors.initials: M
authors.lastname: Gunduzoz
authors.affiliation: Department of Cardiology, Kecioren Research and Training Hospital, Ankara, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ayturk
authors.affiliation: Department of Cardiology, Kecioren Research and Training Hospital, Ankara, Turkey.
authors.forename: Mujgan
authors.initials: M
authors.lastname: Tek Ozturk
authors.affiliation: Department of Public Health, Faculty of Medicine, Bozok University, Yozgat, Turkey.
authors.forename: Engin
authors.initials: E
authors.lastname: Tutkun
authors.affiliation: Department of Clinical Toxicology, Occupational Diseases Hospital, Ankara, Turkey.
authors.forename: Omer Hinc
authors.initials: OH
authors.lastname: Yilmaz
mesh_terms: D000328:Adult; D001151:Arsenic; D020261:Arsenic Poisoning / Q000503:physiopathology*; D002318:Cardiovascular Diseases / Q000139:chemically induced*; D003430:Cross-Sectional Studies; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data; D015444:Exercise; D005080:Exercise Test / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008297:Male; D020127:Recovery of Function
chemical_list: D001151:Arsenic
keywords: arsenic exposure; chronotropic incompetence; heart rate recovery