Evaluation of Systemic Microvascular Endothelial Function in Metabolically Healthy Obesity

Study Overview
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Brief Summary
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Obesity is known to be a risk factor for cardiovascular disease (CVD), type 2 diabetes mellitus, gastrointestinal tract disease, respiratory problems (such as obstructive sleep apnea), joint and muscle problems, reproductive disorders, depression and cancer. However, recently a new classification has emerged about obesity, the metabolically healthy obesity (MHO). According to the definition of the term, MHO represents obesity that occurs segregated from the metabolic syndrome criteria defined by the International Diabetes Federation (IDF). However, as there is still disagreement about the definition of MHO, the cardiovascular risk of these individuals is also uncertain. This phenotype may present as an intermediate risk between metabolically healthy normal-weight individuals and metabolically unhealthy obese individuals (MUO) or as a transition stage of the disease; when evolving to MUO, represents a higher risk of developing CVDs. The hypothesis of the present study is that obese individuals classified as metabolically healthy have worse vascular endothelial function when compared to non-obese individuals, demonstrating increased cardiovascular risk even in this subgroup considered low risk. The detection of endothelial dysfunction in metabolically healthy obese may help in the prevention, treatment and follow-up of these individuals, aiming to reduce the development and morbidity and mortality of CVD. In the present study, the investigators will use a laser-based method for evaluating non-invasive, operator-independent systemic microvascular function that detects microvascular flow in the skin for the evaluation of systemic vascular endothelial function.

Official Title
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Evaluation of Systemic Microvascular Endothelial Function in Metabolically Healthy Obesity

Conditions
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Obesity, Dyslipidemias

Intervention / Treatment
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* Diagnostic Test: Evaluation of systemic skin microvascular endothelial function


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • obese individuals (BMI ≥ 30.0 kg / m2) meeting the criteria for metabolically healthy obesity Exclusion Criteria: Pregnancy or lactation. Endocrine disorders except diabetes, cardiovascular disease except systemic arterial hypertension, autoimmune diseases, malignant neoplasms.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: healthy volunteers<br>metabolically healthy eutrophic individuals (BMI ≥18.5 and <25 kg / m2) without any IDF criteria for metabolic syndrome | Diagnostic Test: Evaluation of systemic skin microvascular endothelial function<br>* Laser-based method for evaluating non-invasive, operator-independent systemic microvascular function that detects microvascular flow in the skin for the evaluation of systemic vascular endothelial function.<br>|
| Experimental: metabolically healthy obesity<br>obese individuals (BMI ≥ 30.0 kg / m2) meeting the criteria for metabolically healthy obesity | Diagnostic Test: Evaluation of systemic skin microvascular endothelial function<br>* Laser-based method for evaluating non-invasive, operator-independent systemic microvascular function that detects microvascular flow in the skin for the evaluation of systemic vascular endothelial function.<br>|
| Experimental: metabolically unhealthy obesity<br>volunteers diagnosed with metabolically unhealthy obesity | Diagnostic Test: Evaluation of systemic skin microvascular endothelial function<br>* Laser-based method for evaluating non-invasive, operator-independent systemic microvascular function that detects microvascular flow in the skin for the evaluation of systemic vascular endothelial function.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Baseline and post-iontophoresis of acetylcholine endothelium-dependent skin microvascular reactivity | Evaluation of systemic microvascular reactivity induced by endothelium-dependent agents. Microvascular reactivity will be evaluated using a non-invasive and operator -independent methodology, named laser speckle contrast imaging, coupled with skin iontophoresis of vasodilator agents. Cutaneous microvascular flow will be measured in arbitrary perfusion units, divided by mean arterial pressure, to yield cutaneous vascular conductance. | Microvascular reactivity will be evaluated after a 20-minute rest in the supine position in a temperature-controlled room. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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laser speckle contrast imaging