Effects of Inspiratory Muscle Training on Blood Pressure Levels in Hypertensive Individuals

Not Applicable

• Conditions: Hypertension
• Interventions: Other: Sham IMT; Other: Inspiratory muscle training (IMT)

• Registration Number: NCT02275377
• Lead Sponsor: Hospital de Clinicas de Porto Alegre

Brief Summary

This research aims to evaluate the effects of inspiratory muscle training (IMT) on blood pressure, in inspiratory muscle mechanoreflex, autonomic cardiovascular control in subjects with hypertension.

Detailed Description

Patients with hypertension will be selected through the Outpatient Hypertension of the Hospital of Clinics de Porto Alegre, for convenience. Subsequently, patients will be subjected to test respiratory muscle strength (manometer), respiratory muscle resistance, cardiopulmonary exercise testing (maximum), evaluation of cardiac reflex sensitivity and autonomic control test and induction of inspiratory muscle mechanoreflex with occlusion plethysmography at baseline before the start of the training protocol. Patients will randomize inspiratory muscle training for 30 minutes a day, 7 days a week, for 8 weeks with muscle training device (PowerBreathe). There will be a weekly monitoring in the Clinical Research Center of the institution where the maximal inspiratory pressure (MIP) and respiratory training techniques will be reassessed and readjusted (40% of MIP). The control group will be submitted to respiratory training techniques with muscle training device (PowerBreathe) without load. After this period, all initial tests will be reassessed. A healthy control group study with 10 normotensive individuals will be included.

Study Timeline

• Study First Submitted: 2014-09-30
• Study Start: 2014-10
• Study First Submitted QC: 2014-10-23
• Study First Posted: 2014-10-27
• Status Verified: 2015-05
• Last Update Submitted: 2015-05-18
• Last Update Posted: 2015-05-19
• Primary Completion: 2015-10
• Study Completion: 2015-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

Participants will be selected from the medical records in search of Basic Health Unit and Hypertension Clinic - Hospital of Clinics of Porto Alegre (HCPA), Porto Alegre - RS:

• Diagnosis of essential hypertension with systolic blood pressure ≥140 mmHg and / or diastolic blood pressure ≥ 90 mmHg without treatment or use of antihypertensive;

• Only taking diuretics (monotherapy) or none;

• Body mass index ≤ 29.9 kg / m²;

• Not engaged in physical activity;

• Inspiratory muscle strength ≥ 70% of predicted.

  • Inclusion of normotensive individuals with systolic blood pressure <130 mmHg and/or diastolic blood pressure <85 mmHg by ambulatory blood pressure monitoring (ABPM).

Exclusion Criteria

• Blood pressure ≥ 160/100 mmHg
• Pregnant and lactating women;
• Deep vein thrombosis; current or previous.
• Diabetes mellitus;
• Orthopedic impairments, musculoskeletal, neurological and / or cognitive impairment, or even other diseases that compromise participation in the proposed protocol;
• Acute myocardial infarction within the last 6 months;
• Hearth failure;
• Angina pectoris;
• Pulmonary impairment from any source;
• Current smoking.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Sham IMT	Sham IMT	Participants will be submitted to inspiratory muscle training with the same equipment as the intervention group, but without a load generating resistance.
Inspiratory muscle training (IMT)	Inspiratory muscle training (IMT)	Participants will be submitted to a linear pressure resistance (PowerBreathe) with an inspiratory load of 40% of maximal inspiratory pressure (adjusted weekly), seven days a week, session duration of 30 minutes for 8 weeks.

Primary Outcome Measures

Name	Time	Method
Levels of blood pressure (mmHg)	8 weeks	Ambulatory blood pressure monitoring (ABPM).

Secondary Outcome Measures

Name	Time	Method
Inspiratory muscle mechanoreflex	8 weeks	Venous occlusion plethysmography measure during inspiratory muscle training exercise at 60% and 2% of maximal inspiratory muscle strength.
Cardiopulmonary Capacity	8 weeks	High-intensity exercise test (maximum) assessed by ergometry with noninvasive hemodynamic monitoring (electrocardiogram, exhaled gas analyzer, heart rate, respiratory rate and blood pressure).
Autonomic cardiovascular control	8 weeks	Heart rate and blood pressure monitoring in the time domain (spectral analysis).

Trial Locations

Locations (1)

Leila Moreira; 🇧🇷 Porto Alegre, Rio Grande do Sul, Brazil