title: Does respiratory muscle training improve cough flow in acute stroke? Pilot randomized controlled trial.
abstract: OBJECTIVE
  Cough protects the lungs from aspiration. We investigated whether respiratory muscle training may improve respiratory muscle and cough function, and potentially reduce pneumonia risk in acute stroke.
  
  
  METHODS
  We conducted a single-blind randomized placebo-controlled trial in 82 patients with stroke (mean age, 64±14 years; 49 men) within 2 weeks of stroke onset. Participants were masked to treatment allocation and randomized to 4 weeks of daily expiratory (n=27), inspiratory (n=26), or sham training (n=25), using threshold resistance devices. Primary outcome was the change in peak expiratory cough flow of maximal voluntary cough. Intention-to-treat analyses were conducted using ANCOVA, adjusting for baseline prognostic covariates.
  
  
  RESULTS
  There were significant improvements in the mean maximal inspiratory (14 cmH2O; P<0.0001) and expiratory (15 cmH2O; P<0.0001) mouth pressure and peak expiratory cough flow of voluntary cough (74 L/min; P=0.0002) between baseline and 28 days in all groups. Peak expiratory cough flow of capsaicin-induced reflex cough was unchanged. There were no between-group differences that could be attributed to respiratory muscle training. There were also no differences in the 90-day incidence of pneumonia between the groups (P=0.65).
  
  
  CONCLUSIONS
  Respiratory muscle function and cough flow improve with time after acute stroke. Additional inspiratory or expiratory respiratory muscle training does not augment or expedite this improvement.
  
  
  BACKGROUND
  http://www.controlled-trials.com. Unique identifier: ISRCTN40298220.
authors.affiliation: From the Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (S.T.K., L.K.), Department of Respiratory Medicine and Allergy, School of Medicine (S.S.B., G.F.R.), King's College London, United Kingdom; and Department of Respiratory Medicine and Allergy, King's Health Partners, London, United Kingdom (J.M.). stefan.s.kulnik@kcl.ac.uk.
authors.forename: Stefan Tino
authors.initials: ST
authors.lastname: Kulnik
authors.affiliation: From the Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (S.T.K., L.K.), Department of Respiratory Medicine and Allergy, School of Medicine (S.S.B., G.F.R.), King's College London, United Kingdom; and Department of Respiratory Medicine and Allergy, King's Health Partners, London, United Kingdom (J.M.).
authors.forename: Surinder Singh
authors.initials: SS
authors.lastname: Birring
authors.affiliation: From the Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (S.T.K., L.K.), Department of Respiratory Medicine and Allergy, School of Medicine (S.S.B., G.F.R.), King's College London, United Kingdom; and Department of Respiratory Medicine and Allergy, King's Health Partners, London, United Kingdom (J.M.).
authors.forename: John
authors.initials: J
authors.lastname: Moxham
authors.affiliation: From the Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (S.T.K., L.K.), Department of Respiratory Medicine and Allergy, School of Medicine (S.S.B., G.F.R.), King's College London, United Kingdom; and Department of Respiratory Medicine and Allergy, King's Health Partners, London, United Kingdom (J.M.).
authors.forename: Gerrard Francis
authors.initials: GF
authors.lastname: Rafferty
authors.affiliation: From the Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (S.T.K., L.K.), Department of Respiratory Medicine and Allergy, School of Medicine (S.S.B., G.F.R.), King's College London, United Kingdom; and Department of Respiratory Medicine and Allergy, King's Health Partners, London, United Kingdom (J.M.).
authors.forename: Lalit
authors.initials: L
authors.lastname: Kalra
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001945:Breathing Exercises / Q000379:methods* / Q000639:trends; D003371:Cough / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012132:Respiratory Muscles; D016037:Single-Blind Method; D020521:Stroke / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*
keywords: breathing exercises; cough; pneumonia; prevention and control; rehabilitation; stroke