title: Effects of low-dose morphine on perceived sleep quality in patients with refractory breathlessness: A hypothesis generating study.
abstract: OBJECTIVE
  The management of chronic refractory breathlessness is one of the indications for regular low-dose (≤30 mg/24 h) oral sustained release morphine. Morphine may disrupt sleep in some conditions and improve sleep quality in others. This study aimed to determine any signal of regular, low-dose morphine on perceived sleep disruption due to breathlessness and perceived sleep quality.
  
  
  METHODS
  This is a secondary analysis of data from 38 participants with refractory breathlessness (30 male; 33 with COPD) aged 76 ± 0.9 years who completed a double-blind, randomized, placebo-controlled, cross-over study in which they received 20 mg oral sustained release morphine daily and placebo for 4 days each. Participant ratings of sleep disruption due to breathlessness and perceived sleep quality were obtained daily throughout the 8-day trial.
  
  
  RESULTS
  Perceived sleep disruption due to breathlessness over the 4-day period ranged between 13% and 32% of participants for placebo and 13% and 26% for morphine, decreasing by each day of the study during the morphine arm. Most participants reported 'very good' or 'quite good' sleep throughout the trial and were less likely to perceive poor sleep quality during the morphine arm (odds ratio = 0.55, 95% confidence interval: 0.34-0.88, P = 0.01). Participants who reported decreased breathlessness during the 4 days on morphine were also likely to report improved sleep quality with morphine (P = 0.039).
  
  
  CONCLUSIONS
  Four days of low-dose morphine improved perceived sleep quality in elderly participants with refractory breathlessness. Regular low-dose morphine targeted to reduce refractory breathlessness may yield associated benefits by reducing sleep disruption and improving sleep quality.
authors.affiliation: Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia.|School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Rodrigo T
authors.initials: RT
authors.lastname: Martins
authors.affiliation: Discipline, Palliative and Supportive Services, Flinders University, Bedford Park, South Australia, Australia.
authors.forename: David C
authors.initials: DC
authors.lastname: Currow
authors.affiliation: Department of Medicine, Division on Medical Oncology and the Center for Learning Health Care, Duke Clinical Research Institute, Duke University, Durham, North Carolina, USA.
authors.forename: Amy P
authors.initials: AP
authors.lastname: Abernethy
authors.affiliation: Hull York Medical School, The University of Hull, Hull, UK.
authors.forename: Miriam J
authors.initials: MJ
authors.lastname: Johnson
authors.affiliation: Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Toson
authors.affiliation: Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia.|School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Danny J
authors.initials: DJ
authors.lastname: Eckert
mesh_terms: D000284:Administration, Oral; D000368:Aged; D002908:Chronic Disease; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D004417:Dyspnea / Q000150:complications* / Q000188:drug therapy*; D020920:Dyssomnias / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D009020:Morphine / Q000008:administration & dosage*; D009294:Narcotics / Q000008:administration & dosage*; D010465:Perception; D012890:Sleep / Q000187:drug effects*
chemical_list: D003692:Delayed-Action Preparations; D009294:Narcotics; D009020:Morphine
keywords: chronic obstructive pulmonary disease; controlled clinical trials; dyspnoea; opioid; sleep-disordered breathing