Inspiratory Muscle Strength Training for Sleep-related Breathing Disorders

Not Applicable

Completed

• Conditions: Obstructive Sleep Apnea
• Interventions: Other: Inspiratory muscle strength training; Other: Placebo

• Registration Number: NCT02709941
• Lead Sponsor: University of Arizona

Brief Summary

The purpose of the current study is to investigate the effects of a novel breathing training, called inspiratory muscle strength training (IMST), on sleep patterns, breathing and blood pressure for patients diagnosed with mild, moderate and severe sleep apnea.

Detailed Description

Aims of the study:

1. To determine the influence of IMST on resting blood pressure and baroreceptor sensitivity.

2. To determine the effect of IMST on sympathetic nervous system by measuring plasma cathecholamines and nerve recording (MSNA).

Population:

30 subjects aged 30-75 years, who have previously been diagnosed with obstructive sleep apnea, as defined by the National Institutes of Health (National Heart Lung, and Blood Institute) will be included in this study.

Study Protocol:

* Pre-training assessment and overnight sleep study

* 5-10 minutes each day breathing training (IMST) at home using a hand-held device for 6 weeks

* Once weekly laboratory visit

* Post-training assessment and overnight sleep study

Pre- and post-training assessment include blood pressure measurement, body weight, neck circumference, cardiorespiratory monitoring, nerve recording, blood draw and sleep surveys.

Study Timeline

• Study Start: 2016-03
• Study First Submitted: 2016-03-02
• Study First Submitted QC: 2016-03-10
• Study First Posted: 2016-03-16
• Primary Completion: 2017-10
• Study Completion: 2017-10
• Status Verified: 2017-11
• Last Update Submitted: 2017-11-27
• Last Update Posted: 2017-11-29

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 25

Inclusion Criteria

• Age 30-75 years
• Diagnosed with Obstructive Sleep Apnea with Apnea Hypopnea Index (AHI) > 15
• Neck circumference > 16 cm

Exclusion Criteria

• Body mass index (BMI) > 40kg/m2
• Implanted pacemaker
• On anticoagulant medication
• On hypnotic medication
• On immunosuppressive medication
• Acute or recent (3 months prior to study) infection
• History of hypothyroidism
• History of stroke or neuromuscular disease
• Moderate to severe heart failure
• Severe ischemic heart disease
• Severe obstructive and restrictive lung disease
• Cor pulmonale
• Cognitive disorders
• Obstructive nasal disease or history of spontaneous pneumothorax or rib fracture
• History of neurological, respiratory, head /neck, or thoracic surgery

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
IMST Training Group	Inspiratory muscle strength training	Subjects in inspiratory muscle strength training group will complete 30 breaths against a resistance set at 75% of Maximal Inspiratory Pressure (PI Max) everyday for period of 6 weeks.
Placebo Training Group	Placebo	Subjects in placebo training group will complete 30 breaths against a resistance set at 15% of Maximal Inspiratory Pressure (PI Max) everyday for period of 6 weeks.

Primary Outcome Measures

Name	Time	Method
Systolic and diastolic blood pressures (mmHg)	Weekly blood pressure measures obtained each week for 6 weeks	Blood pressure measured with blood pressure cuff and syphygmomanometer via standard auscultation technique.

Secondary Outcome Measures

Name	Time	Method
Apnea hypopnea index	Prior to and upon completion of the 6-weeks respiratory strength training.	Documentation of the total number of apneas and hypopneas experienced by the individuals per hour of sleep and expressed as the apnea-hypopnea index or AHI which has the following ranges; \<5 normal; 5-15 mild, 15-30 moderate and \>30 severe AHI.
Sleep Quality Survey (PSQI)	Prior to and upon completion of the 6-weeks training.	This is a rating scale of overall sleep quality ranging from 0-21 with values \<5 rated as indicative of normal or good sleep quality and a score of 21 indicative of most severe sleep disturbance.
Plasma cathecholamines (epinephrine, norepinephrine and dopamine)	Blood draw taken prior to and upon completion of the 6-weeks respiratory strength training.	Plasma catecholamines are determined via morning blood draw taken after 20 minutes supine rest. Reference ranges for plasma catecholamines are as follows: plasma epinephrine is 10-200 pg/ml; plasma norepinephrine 80-250 pg/ml and plasma dopamine 0-20 pg/ml.

Trial Locations

Locations (1)

Department of Physiology at the University of Arizona; 🇺🇸 Tucson, Arizona, United States