title: Effects of nocturnal oxygen therapy on outcome measures in patients with chronic heart failure and cheyne-stokes respiration.
abstract: BACKGROUND
  The effects of nasal oxygen (O(2)) supply at night using conventional home oxygen therapy (HOT) equipment on quality of life (QOL) and sleep-disordered breathing (SDB) were evaluated in patients with congestive heart failure (CHF). Nasal nocturnal O(2) therapy not only stabilizes SDB but also reduces sympathetic activity, and improves exercise capacity in patients with CHF. However, the effects of oxygen on the cardiac function and QOL of heart failure patients have not been fully elucidated.
  
  
  RESULTS
  Fifty-six patients with CHF (New York Heart Association class II - III, left ventricular ejection fraction (LVEF) <or=45%) and central sleep apnea (CSA) with Cheyne-Stokes respiration (CSR) were randomly assigned to receive either nocturnal O(2) (HOT group, n=25) or usual breathing (control group, n=31) for 12 weeks. Respiration, airflow and arterial oxygen levels were monitored with determination of apnea/hypopnea index (AHI) and oxygen desaturation index (ODI) during sleep. LV function was determined by radionuclide angiography or echocardiography. QOL was assessed by the Specific Activity Scale questionnaire. In the HOT group, nocturnal O(2) resulted in significant improvements in AHI (21.0 +/- 10.8 to 10.0+/-11.6 events/h, mean +/- SD, p<0.001), ODI (19.5 +/- 9.8 to 5.9 +/- 8.7 dips/h, p<0.001) and Specific Activity scale (4.0 +/- 1.2 to 5.0 +/- 1.5 Mets, p<0.001). LVEF also increased from baseline to the end of the study (34.7 +/- 10.4 to 38.2 +/- 13.6%, p=0.022).
  
  
  CONCLUSIONS
  In patients with stable CHF and CSR, HOT at night improves SDB, LV function and QOL, and thus is a valuable nonpharmacological option for the treatment of patients with CHF and CSR-CSA.
authors.affiliation: Hamamatsu Rosai Hospital, Hamamatsu 430-8525, Japan. sasayama@wonder.ocn.ne.jp
authors.forename: Shigetake
authors.initials: S
authors.lastname: Sasayama
authors.forename: Toru
authors.initials: T
authors.lastname: Izumi
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Seino
authors.forename: Kenji
authors.initials: K
authors.lastname: Ueshima
authors.forename: Hidetsugu
authors.initials: H
authors.lastname: Asanoi
mesh_terms: D000328:Adult; D000368:Aged; D002639:Cheyne-Stokes Respiration / Q000628:therapy*; D004334:Drug Administration Schedule; D005260:Female; D006333:Heart Failure / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy; D011788:Quality of Life; D012016:Reference Values; D012890:Sleep; D016277:Ventricular Function, Left