Non-pharmacological Treatment for Essential Isolated Systolic Hypertension in Elderly

Study Overview
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Brief Summary
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The previous studies used the slow loaded breathing device for breathing training (Jones et al., 2010). It has been shown that slow loaded breathing training can reduce resting blood pressure and heart rate in essential hypertensive patients. However, this has not been studied in elderly with essential isolated systolic hypertensive patients. Not only highest prevalence of hypertension in Thailand was found in elderly but also physiological changes in the elderly are cause of interest in this special population. It has many advantages to use a slow loaded breathing training in elderly people. Firstly, it is low technology and easily implemented at home. Secondly, it can be practiced almost anytime and anywhere. Thirdly, the orthopedic complications of slow loaded breathing training are minimal. Finally, slow loaded breathing training may be enhancing cardiopulmonary function and other fitness traits, but it out of scope of this study. Moreover, slow loaded breathing exercise by itself should not result in any metabolic adaptation of skeletal muscles, such as the forearm, which had not been trained. If slow loaded breathing training modified some central component of the pressor reflex pathway in a way that single muscle training might work, as suggested above, then loaded breathing training would have a modulating effect on the pressor responses of muscles that had not been trained. We, therefore, aim to study the effect of slow loaded breathing training by using Breathmax on blood pressure at rest and exercise in elderly with essential isolated systolic hypertension and also investigate the autonomic function and others that may be involved with the changed blood pressure in elderly with essential isolated systolic hypertension. We hypothesized that slow loaded and unloaded breathing training could reduce resting and exercising blood pressure in elderly with essential isolated systolic hypertension.

Detailed Description
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All subjects will be trained for blood pressure and heart rate measurement at home by using a digital arm blood pressure monitoring for 2 weeks control periods before start breathing training. After 2 weeks, subjects in both breathing training groups will trained to inspire deeply against the resistance setting by using Breathmax at the loaded of 18 centimeter of water (cmH2O) and 0 cmH2O (no resistance) with breathing frequency control at 6 breaths/minute in loaded breathing (LB) and unloaded breathing (ULB) group, respectively. They will rest for 5 seconds after every 6 deep breathing. Breathing pattern will be controlled at duty cycle of 0.4 (inspiratory time = 4 sec and total respiratory time = 10 sec). The paced breathing will be practice using metronome at the laboratory until the subjects can do independently without metronome. The breathing was performed normally in control groups (C). The training program will be performed at home for 30 minutes/day, 7 days/week for 8 weeks. After 8 weeks of breathing training, the sustainability of breathing training effect will be assessed. Subjects in both breathing training groups (LB and ULB) will be stop breathing training with Breathmax and change to breathing normally. In contrast with the subjects in control group, they will be divided to 2 subgroups. The first subgroup performed loaded breathing training at the loaded of 18 cmH2O. The another subgroup performed unloaded breathing training at the loaded of 0 cmH2O. Breathing frequency will be control at 6 breaths/minute in both subgroups. The training program will be performed at home for 30 minutes/day, 7 days/week for 8 weeks. Data collection will be carried out for 4 times: (1) before control, (2) before training, (3) after training and (4) after stop training. All measurement will be done in the cardiovascular laboratory room, department of physical therapy, faculty of associated medical sciences. In addition, self measurement of blood pressure and heart rate will be conducted at home every morning after getting up at the same time throughout the study (from week 0 to 18).

Official Title
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Effects of Slow Loaded and Unloaded Breathing Training

Conditions
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Systolic Essential Hypertension

Intervention / Treatment
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* Other: Loaded breathing training
* Other: Unloaded breathing training
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Essential isolated systolic hypertension (stage I- II, based on recommendations of JNC-VII) Good communication Exclusion Criteria: Essential hypertension stage III or secondary hypertension History of respiratory disease, heart disease, renal disease, blindness, deafness and cerebrovascular disease.

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 85 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Placebo<br>The breathing was performed normally in this groups. | Other: Placebo<br>* 7 days/week, for 8 weeks<br>|
| Experimental: Loaded breathing training<br>subjects will trained to inspire deeply against the resistance setting by using BreathMAX® at the loaded of 18 cmH2O with breathing frequency control at 6 breaths/minute. Breathing pattern will be controlled at duty cycle of 0.4 (inspiratory time = 4 sec and total respiratory time = 10 sec). The training program will be performed at home for 30 minutes/day, 7 days/week for 8 weeks. | Other: Loaded breathing training<br>* 7 days/weeks, for 8 weeks<br>|
| Experimental: Unloaded breathing training<br>subjects will trained to inspire deeply (no resistance) with breathing frequency control at 6 breaths/minute. Breathing pattern will be controlled at duty cycle of 0.4 (inspiratory time = 4 sec and total respiratory time = 10 sec). The training program will be performed at home for 30 minutes/day, 7 days/week for 8 weeks. | Other: Unloaded breathing training<br>* 7 days/week, for 8 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting blood pressure |  | 4 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate |  | 4 months | 
| Pulse wave velocity |  | 4 months | 
| Exercise pressure response |  | 4 months | 
| Heart rate variability |  | 4 months | 
| cardiac output |  | 4 months | 
| Flow-mediated dilatation of brachial artery |  | 4 months | 
| Forearm limb blood flow |  | 4 months |