Effects of Bariatric Surgery on Inspiratory Metaboreflex in Obese Subjects

Study Overview
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Brief Summary
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The hypothesis of this study is that reductions in body weight could improve inspiratory muscle function attenuating the inspiratory metaboreflex in metabolically healthy obese individuals and obese individuals with metabolic syndrome.

Detailed Description
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Introduction: Peripheral metaboreflex activation appears to be exacerbated in obese individuals with metabolic syndrome. Interestingly, bariatric surgery attenuates the peripheral metaboreflex. Obese individuals have impaired inspiratory muscle function, which can be reversed by the reduction in body weight. Therefore, bariatric surgery could attenuate inspiratory metaboreflex in metabolically healthy obese individuals and obese individuals with metabolic syndrome. Objectives: To investigate the effects of bariatric surgery on inspiratory metaboreflex in metabolically healthy obese individuals and in obese patients with metabolic syndrome. Patients and Methods: A sample comprising of 15 obese subjects with metabolic syndrome, 15 obese subjects without metabolic syndrome and 15 healthy nonobese individuals. These subjects will be submitted to pulmonary function, respiratory muscle strength, inspiratory muscle resistance, exercise tolerance, quality of life, autonomic cardiovascular control and the inspiratory metaboreflex evaluation. The evaluations performed in obese patients with and without metabolic syndrome pre-surgery will be repeated 6 months after bariatric surgery.

Official Title
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Effects of Bariatric Surgery on Inspiratory Metaboreflex in Metabolically Healthy Obese and Obese Subjects With Metabolic Syndrome

Conditions
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Obesity, Metabolic Syndrome

Intervention / Treatment
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* Other: Bariatric surgery
* Other: Control


Participation Criteria
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Eligibility Criteria
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Obese with Metabolic Syndrome Inclusion Criteria: Body mass index (BMI)> 35 kg / m² Diagnosis of metabolic syndrome Exclusion Criteria: Acute health problems in the last month (viral or bacterial infections, accidents, allergic reactions) Diseases of the nervous system or conditions that affect the understanding or participation in the study Pregnancy Type I diabetes mellitus Arterial hypertension Dyslipidemias Coronary artery disease Left ventricular dysfunction Any condition interfering with locomotion Bronchial asthma Chronic obstructive pulmonary disease Chronic neuropathies Use of drugs such as corticosteroids or bronchodilators Smokers. Obese without Metabolic Syndrome Inclusion Criteria: Body mass index (BMI)> 35 kg / m² Exclusion Criteria: Metabolic Syndrome Acute health problems in the last month (viral or bacterial infections, accidents, allergic reactions) Diseases of the nervous system or conditions that affect the understanding or participation in the study Pregnancy Type I diabetes mellitus Arterial hypertension Dyslipidemias Coronary artery disease Left ventricular dysfunction Any condition interfering with locomotion Bronchial asthma Chronic obstructive pulmonary disease Chronic neuropathies Use of drugs such as corticosteroids or bronchodilators Smokers. Healthy nonobese subjects Inclusion Criteria: BMI <25 kg / m² Exclusion Criteria: Non-smokers Any diagnosed disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Obese with metabolic syndrome<br>bariatric surgery | Other: Bariatric surgery<br>* evaluations pre and post bariatric surgery.<br>|
| Obese without metabolic syndrome<br>bariatric surgery | Other: Bariatric surgery<br>* evaluations pre and post bariatric surgery.<br>|
| Healthy<br>Control | Other: Control<br>* without intervention, it will be performed only evaluations<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inspiratory metaboreflex | It will be induced through a linear inspiratory resistance of 60% of maximal inspiratory pressure | 6 monhs | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pulmonary function | It will be assessed by spirometry | 6 months | 
| Respiratory muscle strength | It will be determined by manovacuometry. | 6 months | 
| Inspiratory muscle resistance | It will be evaluated through a protocol with progressive increase in inspiratory resistance. | 6 months | 
| Autonomic cardiovascular control | It will be determined by spectral analysis | 6 months | 
| Exercise tolerance | It will be determined by the 6-minute walk test. | 6 months | 
| Quality of life | It will be determined through the SF36 questionnaire. | 6 months |