Effects of Inspiratory Muscle Training in Patients With Bronchiectasis
Phase: NA
Conditions: Bronchiectasis
Sponsor: Chang Gung Memorial Hospital

Chang Gung Memorial Hospital 
NCT00952718 
Date: 2019/10/31 
Study Protocol: 
Patients aged 40–80 years from the outpatient clinic of the Department of 
Pulmonology of a tertiary care medical centre who had bronchiectasis were eligible. 
Bronchiectasis was confirmed by clinical history, such as coughing, shortness 
of breath and exertional dyspnoea, pulmonary function tests and high-resolution 
computed tomography. 
Those who were using steroids (including inhalation or oral), had recent exacerbation 
within six weeks, poor consciousness level and cerebrovascular or neuromuscular 
disorders were excluded. The eligible subjects were then randomly divided into 
either inspiratory muscle training or control groups. All technicians who performed 
the different measurements and assessed the outcomes were blinded to 
group allocation, and all measurements were performed at the beginning and end of 
the eightweek programme. The pulmonary function tests were performed in a 
pulmonary functional laboratory using a standard spirometer (Vitalograph, Serial 
Spirotrac, Buckingham, USA) according to the American Thoracic Society 
recommendations, and the measurements included parameters of forced vital 
capacity (FVC), FEV1 and maximum mid-expiratory flow. The best FVC measurement 
was recorded along with FEV1 and FEV1/FVC calculations. 
After pulmonary function parameters were recorded, the bronchodilator test was 
used to check if the participant had a hypersensitive airway. The reversibility of the 
airway obstruction was defined as a 15% or greater improvement in FEV1 and at 
least a 200 mL increase in FEV1. None of our eligible patients showed a   
positive bronchodilator response. All measurements are presented as percentage 
predicted value. Baseline characteristics including height, weight, body mass index 
and duration of the disease, and the resting oxyhaemoglobin saturation (SpO2), 
lowest resting SpO2, Borg Scale during a 6-minute walking test, MIP, maximal 
expiratory pressure (MEP),and St George’s Respiratory Questionnaire (SGRQ) were 
obtained in the Department of Respiratory Therapy. 
SpO2 was measured using a finger pulse oximeter (FingerPrint, BCI International, 
Wisconsin,USA). Resting dyspnoea was quantified using the modified Borg Scale, 
which ranges from 0.5 to 10.27 The 6-minute walk work (6Mwork) value was 
calculated as body mass  distance covered during the 6-minute walking test. 
MEP was measured after maximal inspiration, while MIP was measured after 
maximal expiration with each subject seated and wearing a nose-clip. An 
experienced respiratory therapist strongly urged the subjects to make maximum 

inspiratory and expiratory efforts at or near residual and total lung capacity, 
respectively. 
Determinations were repeated until two technically satisfactory measurements were 
recorded, with the highest value used for calculations. St George’s Respiratory 
Questionnaire has 76 items on symptoms (frequency and severity of respiratory 
symptoms), activity (activities caused or limited by breathlessness), and impact 
(social functioning and psychological disturbances resulting from airway disease) on 
daily life. The scores range from 0 to 100, with higher scores indicating poorer health. 
A mean change score of 4 units was defined as slightly efficacious treatment, 8 
moderately efficacious, and 12 very effective treatment. 
The inspiratory muscle training programme was started at an intensity of 30% MIP, 
and increased by 2 cmH2O each week. A pressure threshold device (Threshold IMT 
HS730, Respironics Inc, Cedar Grove, NJ, USA) was used. During training, patients 
were in a sitting position with a nose-clip and were instructed to place their lips 
around the mouthpiece, inhale with enough force to open the valve, exhale 
through the mouthpiece, and then continue inhaling and exhaling without removing 
the device from their mouths. Patients could take intermittent periods of rest if they 
felt uncomfortable. They were encouraged to perform inspiratory muscle training for 
30 minutes per day, at least five days a week, for eight weeks. If the training sessions 
could not be completed due to increased resistance, the last part of the session was 
performed with the previous resistance setting. 
Patients in the control group did not receive any training programme. Both groups 
were monitored by telephone call once or twice aweek until the end of the study. 
The medication profiles were also recorded. No medication was altered during the 
study period. 
The Institutional Review Board of Chang Gung Memorial Hospital, Kaohsiung Medical 
Center approved the study protocol and all patients provided informed consent. 
 
Statistical analysis 
Baseline characteristics were compared using the Student’s t-test for continuous 
variables and Fisher’s exact test for categorical variables. 
Results are presented as absolute number (percentage) or mean (standard deviation) 
and adjusted for age by linear regression analysis. 
The difference for each variable was compared with two-way repeated measures 
analysis of variance between the two groups and within each group. Paired sample 
T-tests were used for comparison within each group. A two-tailed P-value of less 
than 0.05 was considered significant. All statistical analyses were performed using 
the SPSS 14.0 software package (SPSS Inc., Chicago, IL, USA).