title: Wrist actigraphy predicts outcome in patients with pulmonary hypertension.
abstract: BACKGROUND
  Pulmonary hypertension (PH) impairs quality of life, exercise performance and survival. Simple measures to monitor the disease are needed.
  
  
  OBJECTIVE
  We tested whether actigraphy by a wrist-worn device in the patient's home reflects disease severity in PH patients.
  
  
  METHODS
  Twenty-three outpatients with pulmonary arterial and chronic thromboembolic PH (15 females), functional classes II-IV, underwent clinical examination and actigraphy over 2 weeks while pursuing their usual life at home. Actigraphies were correlated with clinical data and mean pulmonary artery pressure (mPAP). Deaths, lung transplantations and pulmonary endarterectomy were recorded over 4 years.
  
  
  RESULTS
  Actigraphies revealed a mean ± SD daytime activity duration of 14:57 ± 1:14 h with 146 ± 125 activity counts/min. Very severely impaired patients (mPAP 50 ± 7 mm Hg) were inactive for longer periods at night (8:25 ± 1:18 h) and less active during the day (54 ± 44 counts/min) when compared to modestly impaired patients (mPAP 33 ± 7 mm Hg; inactive at night for 6:58 ± 0:39 h; daytime activity 229 ± 148 counts/min, p < 0.05 in all instances). Out of 19 patients followed for 4 years, 5 died and 1 received a lung transplantation. Kaplan-Meier analysis revealed a shorter survival without lung transplantation in patients with a duration of daytime activity of <15 h/day than those with >15 h/day duration (log rank, p = 0.026).
  
  
  CONCLUSIONS
  A long nocturnal rest and reduced daytime activity recorded by actigraphy are associated with severe hemodynamic impairment and reduced survival in patients with PH. Therefore, wrist actigraphy performed during everyday life in the patient's home holds promise as a simple tool for the assessment of disease severity and prognosis in patients with PH.
authors.affiliation: Pulmonary Division and Sleep Disorders Center, Department of Thoracic and Cardiovascular Medicine, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Silvia
authors.initials: S
authors.lastname: Ulrich
authors.forename: Manuel
authors.initials: M
authors.lastname: Fischler
authors.forename: Rudolf
authors.initials: R
authors.lastname: Speich
authors.forename: Konrad E
authors.initials: KE
authors.lastname: Bloch
mesh_terms: D056044:Actigraphy / Q000379:methods*; D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D018572:Disease-Free Survival; D004691:Endarterectomy; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000401:mortality; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D016040:Lung Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011651:Pulmonary Artery / Q000601:surgery; D011669:Pulmonary Wedge Pressure; D012720:Severity of Illness Index; D014953:Wrist