Effects of Slow Breathing on Blood Pressure and Autonomic Function

Study Overview
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Brief Summary
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Hypertension is a chronic disease that affects about 23% of the brazilian population. The treatment of hypertension by pharmacological intervention is efficacious, but has side effects and significant costs. Techniques that reduce the respiratory rate are shown as a effective non-pharmacological treatment in controlling blood pressure. Evidence has shown that a slow and deep breathing rate, around 10 breaths per minute or less, significantly reduces blood pressure. However, the physiological mechanisms involved in blood pressure decrease due to decreased respiratory rate are not yet known. Therefore the goals of this study will evaluate the chronic effect of breathing exercise guided on office and 24 hours blood pressure and analyse the chronic effect of breathing exercise guided over the autonomic function in hypertensive patients in stages 1 and 2.

Official Title
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Effects of Slow Breathing on Blood Pressure and Autonomic Function in Hypertensive Patients

Conditions
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Hypertension

Intervention / Treatment
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* Device: Device-guided breathing (Resperate - InterCure, Israel)
* Other: Listen music


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hypertensive patients with or without use of antihypertensive drug therapy with office systolic blood pressure between 140 and 179 mmHg and / or office diastolic between 90 and 109mmHg). Adults over 18 years. Both genders. Exclusion Criteria: Use of medications that alter sympathetic nerve activity (beta blockers and / or sympatholytics). Use of three or more classes of antihypertensive drugs Secondary Hypertension Chronic Respiratory Disease Diabetes Mellitus. Chronic Kidney Disease with Clearance Creatinine <60 ml/min Congestive heart failure Coronary disease Pregnant BMI > 30 kg/m2

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Listen music<br>After randomization, the patients allocated in this arm will be instructed to listen to calm music for 15 minutes per day during 8 weeks | Other: Listen music<br>* After randomization, the patients allocated in this arm will be instructed to listen to calm music for 15 minutes per day during 8 weeks<br>|
| Active Comparator: Device-guided breathing<br>After randomization, the patients allocated in this arm will be instructed to use a device-guided breathing, for 15 minutes per day during 8 weeks, with the aim to reduce the respiratory frequency to less than 10 breaths/min | Device: Device-guided breathing (Resperate - InterCure, Israel)<br>* After randomization, the patients allocated in this arm will be instructed to use a device-guided breathing, for 15 minutes per day during 8 weeks, with the aim to reduce the respiratory frequency to less than 10 breaths/min<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood pressure reduction | The blood pressure reduction in mmHg will be verified by office blood pressure measurement and ambulatory blood pressure monitoring (ABPM) | 8 weeks after the randomization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| autonomic regulation | The autonomic function will be verified in the beginning and after 8 weeks from randomization as follows: muscle sympathetic nervous activity (MSNA) by microneurography technique (burst/min), plasma catecholamines levels (pg/ml) and heart rate variability by power spectral analysis (ms). | 8 weeks after randomization | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hypertension, device-guided breathing, autonomic function, Resperate