Effects of Inspiratory Muscle Training on the Severity of Obstructive Sleep Apnea in Individuals After Stroke

The prevalence of Obstructive Sleep Apnea (OSA) is high in individuals after a stroke. There are few studies evaluating the effects of inspiratory muscle training (IMT) in individuals with OSA and the findings regarding the possible effect on Apneia/Hipopneia Index (AHI) reduction are still controversial.

This study will test the hypothesis that training of the inspiratory muscles is effective in improving severity of OSA, sleep quality and daytime sleepiness in individuals after stroke participating in a rehabilitation program.

Methods: For this prospective, sigle blinded, randomized clinical trial, people after stroke will be randomly allocated into either experimental or control groups. The experimental group will undertake training of the inspiratory muscles with the PowerBreath Medic Plus regulated at 75% of the subjects' maximal inspiratory pressure (MIP) values, five times/week over five weeks 5 sets of 5 repetitions with 1 set increasing each week. Both groups will participate in the rehabilitation program and will receive the same dose of physiotherapy, speech therapy and aerobic exercise sessions. At baseline and post intervention after the cessation of the interventions, researchers blinded to group allocations will collect all outcome measures.

Study outcomes: Primary outcome will be OSA severity measured using the Apnea/Hypopnea Index (AHI). Secondary outcomes will include inspiratory endurance and pressure, functional independence, sleep quality and daytime sleepiness

The prevalence of Obstructive Sleep Apnea (OSA) is high in individuals after a stroke. The gold standard treatment for OSA is the use of Positive Airway Pressure, but due to the low adherence to this resource, the multidisciplinary approach for the treatment of OSA is becoming the best therapeutic option. There are few studies evaluating the effects of inspiratory muscle training (IMT) in individuals with OSA and the findings regarding the possible effect on Apneia/Hipopneia Index (AHI) reduction are still controversial.

Aims:The primary objective of this study is to identify the effects of IMT on the severity of OSA in indivuals after stroke participating in a rehabilitation program. The secondary objectives are to identify effects of IMT on sleep quality and daytime sleepiness and analyze the correlation between severity of OSA and functional independence, inspiratory endurance and pressure.

Methods: For this prospective, sigle blinded, randomized clinical trial, people after stroke will be randomly allocated into either experimental or control groups. The experimental group will undertake training of the inspiratory muscles with the PowerBreath Medic Plus regulated at 75% of the subjects' maximal inspiratory pressure (MIP) values, five times/week over five weeks 5 sets of 5 repetitions with 1 set increasing each week. Both groups will participate in the rehabilitation program and will receive the same dose of physiotherapy, speech therapy and aerobic exercise sessions. At baseline and post intervention after the cessation of the interventions, researchers blinded to group allocations will collect all outcome measures.

Study outcomes: Primary outcome will be OSA severity measured using the Apnea/Hypopnea Index (AHI). Secondary outcomes will include inspiratory endurance and pressure, functional independence, sleep quality and daytime sleepiness

Eligibility Criteria:
Inclusion Criteria:

* Individuals after stroke of any etiology (ischemic or hemorrhagic), 18 to 80 years age, in a subacute or chronic phase (over 3 months to 5 years); with a diagnosis of OSA, defined as increased AHI (\>5/h) in a polysomnography exam.

Exclusion Criteria:

* Individuals with BMI \> 40, using Positive Airway Pressure during sleep, severe OSA (AHI \> 30), previous diagnosis of severe nasal obstructive disease; craniofacial malformations including signs of dentoskeletal deformities, history of pharyngeal surgery to treat apnea, palatine tonsil hypertrophy (grade III and IV); edentulous people or users of complete dental prostheses; presence of oral apraxia; facial paralysis that prevents lip occlusion; aphasia that compromises the understanding of verbal commands; smokers and former smokers with less than 6 months of smoking cessation, orthopedic changes that include distortions of the rib cage and lung parenchyma diseases and that present other associated neurological diseases.