Inspiratory Muscle Training and Neuromuscular Electrical Stimulation in Chronic Obstructive Pulmonary Disease

Study Overview
=================
Brief Summary
-----------------
Chronic obstructive pulmonary disease (COPD) is a significant current public health problem, characterized by the presence of limited airflow. However, COPD has important manifestations beyond the lungs, the so-called systemic effects. These included dysfunction of peripheral and respiratory muscles. The growing amount of evidence has shown that patients with COPD also present important deficits in postural balance and consequently, increased risk of falling. As an essential part of the management of COPD, pulmonary rehabilitation (PR) alleviates dyspnea and fatigue, improves exercise tolerance and health-related quality of life, and reduces hospital admissions and mortality for COPD patients. Exercise is the key component of PR, which is composed of exercise assessment and training therapy. Currently, two modalities of therapy have been suggested as complementary to pulmonary rehabilitation: inspiratory muscular training (IMT) and neuromuscular electrical stimulation (NMES). Based on the premise that peripheral and respiratory muscle dysfunction can negatively impact postural control of patients with COPD, and given the importance of balance as a modifiable risk factor for falls, it is important to investigate whether the use of these therapeutic modalities (IMT and/or NMES) is capable of improving the short-term effects of pulmonary rehabilitation and also promoting improved balance.

Official Title
-----------------
Effects of Inspiratory Muscle Training and Neuromuscular Electrical Stimulation in Patients With Chronic Obstructive Pulmonary Disease

Conditions
-----------------
Chronic Obstructive Pulmonary Disease

Intervention / Treatment
-----------------
* Device: Multimodal training
* Device: IMT + Pulmonary Rehabilitation
* Device: NMES + Pulmonary Rehabilitation
* Device: Pulmonary Rehabilitation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Clinical diagnosis of COPD, in stages II, III and IV, according to criteria of the Global Initiative for COPD (GOLD); Clinically stable, i.e., absence of infections or exacerbations in the last 3 months; Medical team allows patient to exercise Availability of attending the rehabilitation program. Exclusion Criteria: Unstable primary pathologies (cardiovascular, renal, metabolic, psychiatric); Hemodynamic instability; Nutritional supplementation on the 4 weeks preceding the study; Severe hearing or visual impairment recorded on patient chart or self-referred; Obesity (BMI > 30 kg/m2); Neurological or musculoskeletal condition that severely limits mobility and postural control, thus making it impossible to carry out the assessments; Electronic devices, such as heart pacemakers and implantable cardioverter defibrillator; Skin injuries and infection where electrodes would be placed; Prior participation in pulmonary rehabilitation programs 3 months previous to the study; Vertigo; Active smoker and/or alcoholic; Neurological impairment or cerebellar lesions; Deficit in cognitive function; Severe vitamin D deficiency; Physically active.

Ages Eligible for Study
-----------------
Minimum Age: 55 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Multimodal training<br>IMT + NMES + Pulmonary Rehabilitation IMT will be performed using a device with linear load pressure (POWERbreathe Medic Plus ®, SP, BR). NMES will be applied using an calibrated electrical stimulator (Neurodyn High Volt, IBRAMED, São Paulo/São Paulo, Brazil). Pulmonary Rehabilitation: The physical training part of pulmonary rehabilitation will consist of aerobic and resistance exercise. | Device: Multimodal training<br>* IMT will be performed using the POWERbreathe® Medic Plus inspiratory training device for five sets of 10 repetitions each, with a one-minute interval between each set. The initial load set will be 30% of maximal inspiratory pressure (MIP), during the first two weeks to allow for an adjustment period. The IMT wil be performed two times per week for 8 weeks. NMES will be applied using an calibrated electrical stimulator (Neurodyn High Volt, IBRAMED, São Paulo/São Paulo, Brazil). The following parameters will be used: 50 Hz frequency, pulse duration of 400 µs, work cycle of 5 seconds ON and 15 seconds OFF (first month) adjusted for 10 seconds ON and 30 seconds OFF (second month) and maximum intensity tolerated during 2 times per week for 8 weeks. Pulmonary Rehabilitation The pulmonary rehabilitation will consist of aerobic and resistance exercise during 8 weeks.<br>|
| Experimental: IMT + Pulmonary Rehabilitation<br>IMT will be performed using a device with linear load pressure (POWERbreathe Medic Plus ®, SP, BR). Pulmonary Rehabilitation: The physical training part of pulmonary rehabilitation will consist of aerobic and resistance exercise. | Device: IMT + Pulmonary Rehabilitation<br>* IMT will be performed using the POWERbreathe® Medic Plus (POWERbreathe Medic Plus ®, SP, BR) inspiratory training device for five sets of 10 repetitions each, with a one-minute interval between each set. The initial load set will be 30% of maximal inspiratory pressure (MIP), during the first two weeks to allow for an adjustment period. After that, load increases occurred as follows: 35% of MIP in week 3, 40% of MIP in week 4, 45% of MIP in week 5, 50% of MIP at week 6, 55% of MIP in week 7, and 60% of MIP in weeks 8. Pulmonary Rehabilitation The pulmonary rehabilitation will consist of aerobic and resistance exercise during 8 weeks.<br>|
| Experimental: NMES + Pulmonary Rehabilitation<br>NMES will be applied using an calibrated electrical stimulator (Neurodyn High Volt, IBRAMED, São Paulo/São Paulo, Brazil). Pulmonary Rehabilitation: The physical training part of pulmonary rehabilitation will consist of aerobic and resistance exercise. | Device: NMES + Pulmonary Rehabilitation<br>* NMES will be applied using an calibrated electrical stimulator (Neurodyn High Volt, IBRAMED, São Paulo/São Paulo, Brazil). The following parameters will be used: 50 Hz frequency, pulse duration of 400 µs, work cycle of 5 seconds ON and 15 seconds OFF (first month) adjusted for 10 seconds ON and 30 seconds OFF (second month) and maximum intensity tolerated during 2 times per week for 8 weeks. Pulmonary Rehabilitation The pulmonary rehabilitation will consist of aerobic and resistance exercise during 8 weeks.<br>|
| Placebo Comparator: Pulmonary Rehabilitation<br>Pulmonary Rehabilitation: The physical training part of pulmonary rehabilitation will consist of aerobic and resistance exercise. | Device: Pulmonary Rehabilitation<br>* Pulmonary Rehabilitation The pulmonary rehabilitation will consist of aerobic and resistance exercise during 8 weeks.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Static postural balance | Static postural balance will be assessed on a portable force platform (AccuSway Plus, AMTI®, MA, USA) using the center of pressure displacement amplitude in the anteroposterior direction (COP) (cm). | Post-intervention (change after 8 weeks of training) | 
| Static postural balance | Static postural balance will be assessed on a portable force platform (AccuSway Plus, AMTI®, MA, USA) using the area of ellipse (AE) (cm2). | Post-intervention (change after 8 weeks of training) | 
| Static postural balance | Static postural balance will be assessed on a portable force platform (AccuSway Plus, AMTI®, MA, USA) using the velocity of displacement of center of pressure (COPvel) (cm/s). | Post-intervention (change after 8 weeks of training) | 
| Static postural balance | Static postural balance will be assessed on a portable force platform (AccuSway Plus, AMTI®, MA, USA) using the center of area of pressure and area of ellipse (AE) (cm2). | Post-intervention (change after 8 weeks of training) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Static postural balance | Static postural balance (%) will assessed through Foam-Laser dynamic posturography. | Post-intervention (change after 8 weeks of training) | 
| Static and dynamic postural balance | Static and dynamic postural balance will assessed using the Berg Balance Scale (score points). Scores range from 0 to 56, with higher scores indicating better balance. | Post-intervention (change after 8 weeks of training) | 
| Static and dynamic postural balance | Static and dynamic postural balance will assessed using the Balance Evaluation Systems Test (score points). The total score of the test (108 points) will be calculated with a percentage score (0-100%) and higher scores indicate better balance performance. | Post-intervention (change after 8 weeks of training) | 
| Dynamic postural balance | Dynamic postural balance will assessed using the Timed Up and Go (seconds). A faster time indicate a better functional performance and a score of ≥12 seconds used as a cut-point. | Post-intervention (change after 8 weeks of training) | 
| Balance confidence questionnaire | Balance confidence questionnaire will measured through the Activities Specific Balance Confidence Scale (total score points). The questionnaire contains 16 items scored on a range from 0% to 100% (0 indicating no confidence and 100 indicating full confidence). | Post-intervention (change after 8 weeks of training) | 
| Balance confidence questionnaire | Balance confidence questionnaire will measured through Falls Efficacy Scale-International (total score points). The total score ranges from 16 to 64 points. Higher values indicate less fall-related self-efficacy (and more concern about falling). | Post-intervention (change after 8 weeks of training) | 
| Peripheral muscle strength | Handgrip strength and quadriceps muscle strength will be assessed by dynamometry, respectively, Kgf and Newtons. | Post-intervention (change after 8 weeks of training) | 
| Respiratory muscle strength and inspiratory muscle endurance | Respiratory muscle strength (cmH2O) and inspiratory muscle endurance (cmH2O) will measured through digital pressure manometry and incremental and constant test, respectively | Post-intervention (change after 8 weeks of training) | 
| Quadriceps femoris and diaphragm thickness | Quadriceps femoris and diaphragm thickness will measured by ultrasonography | Post-intervention (change after 8 weeks of training) | 
| Submaximal level of functional capacity | Submaximal level of functional capacity will measured by 6-minute walk test | Post-intervention (change after 8 weeks of training) | 
| Health-related quality of life at 8 week | Health-related quality of life will measured by Saint George's Respiratory Questionnaire. Overall scores range from 0 (no effect on quality of life) to a maximum score of 100 (maximum perceived distress). | Post-intervention (change after 8 weeks of training) | 
| Oxidant profile | The oxidant profile will be assessed by Dichlorofluorescein Diacetate - DCF-DA (picomoles / mL). | Post-intervention (change after 8 weeks of training) | 
| Oxidant profile | The oxidant profile will be assessed by Thiobarbituric Acid Reactive Substances -TBARS (nmol de MDA/mL). | Post-intervention (change after 8 weeks of training) | 
| Oxidant profile | The oxidant profile will be assessed by Advanced Oxidation Protein Products - AOPPs (µmol/L). | Post-intervention (change after 8 weeks of training) | 
| Oxidant profile | The oxidant profile will be assessed by Total Oxidant Status - TOS (mmol Trolox Equiv/L). | Post-intervention (change after 8 weeks of training) | 
| Antioxidant profile | The antioxidant profile will be assessed by Ferric Reducing Antioxidant Power - FRAP- (µmol/L) | Post-intervention (change after 8 weeks of training) | 
| Antioxidant profile | The antioxidant profile will be assessed by Total Antioxidant Capacity- CAT (mmol Trolox Equiv/L). | Post-intervention (change after 8 weeks of training) | 
| Muscle damage | Muscle damage will assessed through creatine phosphokinase (total CPK) (U/L). | Post-intervention (change after 8 weeks of training) | 
| Muscle damage | Muscle damage will assessed through lactate dehydrogenase (LDH) (U/L). | Post-intervention (change after 8 weeks of training) | 
| Muscle damage | Muscle damage will assessed through lactate parameter (mg/dL). | Post-intervention (change after 8 weeks of training) | 
| DNA damage | DNA damage will assessed by means of the Comet and micronucleus assay | Post-intervention (change after 8 weeks of training) | 
| Endothelial function | Endothelial function will assessed through nitrite/nitrate oxide (NOx) (µmol/L) | Post-intervention (change after 8 weeks of training) | 
| Peripheral muscle resistance of the lower limbs | Peripheral muscle resistance of the lower limbs will assessed through 30-second Sit-to-Stand tests (repetitions) | Post-intervention (change after 8 weeks of training) |