Cardiovascular Responses to Exercise in People Living With HIV/AIDS: Effects of Exercise Training

Study Overview
=================
Brief Summary
-----------------
Patients living with HIV (PLWHIV) have compromised muscle metaboreflex, which can cause exercise intolerance. This randomized controlled clinical trial will verify the effects of regular exercise on autonomic and hemodynamic responses to muscle ergoreflex activation in these patients. PLWHIV without regular physical exercise will be randomly assigned into an exercise training or a control group. The exercise training group will undergo regular physical exercise during 12 weeks (60-min session performed 3 times/wk with moderate intensity), while the control group will keep inactive. Another group consisted of inactive HIV-uninfected group will be included. The primary endpoints will be blood pressure and autonomic markers in response to the Stroop Color-Word Test and the activation of muscle ergoreflex, by means of the post-exercise circulatory arrest (PECA), which will be performed with and without the topical application of a capsaicin-based analgesic balm. Secondary endpoints will include heart rate, peripheral vascular resistance, stroke volume, cardiac output, blood lactate concentration, anthropometrics, and handgrip strength. The active and inactive PLWHIV groups will be evaluated before and after the exercise training, while the healthy group only at baseline.

Detailed Description
-----------------
HIV-infection is associated to a reduced maximal cardiac output and blunted pressor reflex response to static handgrip exercise, which are suggestive of impaired ergoreflex activation. An abnormal ergoreflex activation may lead to exercise intolerance and increases in cardiovascular risk. Despite the importance of therapeutic strategies in reducing the cardiovascular risk among patients living with HIV, exercise-related effects on ergoreflex sensitivity in these population have not been previously investigated.

Official Title
-----------------
Autonomic and Hemodynamic Responses to Muscular Ergoreflex Activation in People Living With HIV/AIDS: Effects of Exercise Training.

Conditions
-----------------
HIV Infections

Intervention / Treatment
-----------------
* Behavioral: Exercise training


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria for people living with HIV: diagnosis of HIv infection for at least 5 years; use of combined antiretroviral therapy for at least 3 years; asymptomatic and free from opportunistic diseases at enrollment. Exclusion Criteria: regular physical exercise; malnutrition; presence of coronary artery disease, ischemic diseases, pulmonary disease, diabetes, Chagas disease, tuberculosis, heart failure, hypertension; using pacemakers and/or antidepressant, antiarrhythmic or antihypertensive medication, especially beta-blockers.

Ages Eligible for Study
-----------------
Minimum Age: 30 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: HIV+active group will perform exercise training, while HIV+inactive and HIV- groups will not undergo intervention.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active HIV-infected patients<br>Exercise training | Behavioral: Exercise training<br>* Exercise training performed during 12 weeks, 3 sessions per week of 60 minutes of strength and aerobic exercises.<br>|
| No Intervention: Inactive HIV-infected patients<br>No intervention. | |
| No Intervention: Healthy subjects<br>No intervention. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline Blood Pressure at 3 months | Blood pressure will be assessed by a digital sphygmomanometer. | Baseline and 3 months of follow-up | 
| Change from Baseline Heart Rate Variability at 3 months | Heart rate variability will be assessed by a heart rate monitor. | Baseline and 3 months of follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline Heart Rate at 3 months | Heart rate will be evaluated beat-to-beat by means of a heart rate monitor. | Baseline and 3 months of follow-up | 
| Change from Baseline Peripheral Vascular Resistance at 3 months | Peripheral Vascular Resistance will be evaluated by photpletismography. | Baseline and 3 months of follow-up | 
| Change from Baseline Stroke Volume at 3 months | Stroke Volume will be evaluated by photoplethysmography. | Baseline and 3 months of follow-up | 
| Change from Baseline Cardiac Output at 3 months | Cardiac Output will be evaluated by photoplethysmography. | Baseline and 3 months of follow-up | 
| Change from Baseline Blood Lactate at 3 months | Blood Lactate will be determined by the YSL 2700 analyzer. | Baseline and 3 months of follow-up. | 
| Change from Baseline Anthropometric markers at 3 months | Anthropometric markers will be determined by a digital scale and wall-mounted stadiometer. | Baseline and 3 months of follow-up. | 
| Change from Baseline handgrip maximal voluntary contraction at 3 months | Handgrip maximal voluntary contraction will be assessed using a hydraulic handgrip dynamometer. | Baseline and 3 months of follow-up. |