Effects of Combined Inspiratory Muscle Training and Positive Expiratory Pressure Therapy on Pulmonary Function, Respiratory Muscle Strength, Exercise Capacity and Dyspnea in Stable Group E COPD Patients
Effects of Combined Inspiratory Muscle Training and Positive Expiratory Pressure Therapy on Pulmonary Function, Respiratory Muscle Strength, Exercise Capacity and Dyspnea in Stable Group E COPD Patients
Background:
Inspiratory muscle training combined with positive expiratory pressure (IMT/PEP) may improve outcomes in chronic obstructive pulmonary disease (COPD), but evidence in exacerbation-prone (Group E) disease is limited. This study is designed to evaluate the effects of IMT/PEP on pulmonary function, respiratory muscle strength, exercise capacity, and dyspnea in stable Group E COPD.
Methods :
This prospective randomized controlled trial will enroll 62 patients with stable Group E COPD between June 2023 and September 2024. Participants will be randomized to receive IMT/PEP plus standard care or standard care alone. Pulmonary function tests, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), six-minute walk test (6MWT), oxygen saturation (SO₂), and dyspnea scales (mMRC, CAT, MBS, VAS) will be assessed at baseline, 1 month, and 3 months.
Inclusion Criteria:
Age ≥ 40 years
Diagnosis of Group E COPD according to GOLD 2023 criteria
Post-bronchodilator FEV₁/FVC < 0.70 and FEV₁ < 50% predicted
mMRC score ≥ 2 or CAT score ≥ 10
History of ≥2 exacerbations or ≥1 hospitalization in the past year
Stable clinical condition (no exacerbation in the past 2 weeks)
Ability and willingness to perform IMT/PEP therapy
Provided written informed consent
Exclusion Criteria:
Acute exacerbation of COPD at time of enrollment
Contraindications to pulmonary function testing or 6-minute walk test (e.g., recent myocardial infarction, unstable angina)
Inability to perform inspiratory or expiratory maneuvers reliably (e.g., due to cognitive or neuromuscular disorders)
Significant orofacial muscle weakness unresponsive to modified mouthpiece
Participation in another interventional study within the past 3 months
Nonadherence to COPD treatment plan
Any condition deemed by investigators to interfere with study participation