Use of EndoPAT for Measurements of Endothelial Dysfunction in HIV Infected Children and Healthy Controls

Study Overview
=================
Brief Summary
-----------------
Our objective is to determine whether HIV infected youth have higher level of endothelial dysfunction, as measured by Peripheral Arterial Tonometry, when compared to age matched healthy controls. The investigators also aim to gather preliminary data on whether endothelial Peripheral Arterial Tonometry (endoPAT) measurements of endothelial dysfunction are independently associated with HIV and antiretroviral factors, and with markers of inflammation and traditional cardiovascular disease risk.

Detailed Description
-----------------
Study Objectives and Hypothesis Our objective is to determine whether HIV infected youth have higher level of endothelial dysfunction, as measured by Peripheral Arterial Tonometry, when compared to age matched healthy controls. We also aim to gather preliminary data on whether endoPAT measurements of endothelial dysfunction are independently associated with HIV and antiretroviral factors, and with markers of inflammation and traditional cardiovascular disease risk. Specific Aim 1: To compare endothelial function, as measured by endoPAT, between HIV-infected youth and matched healthy controls. Hypothesis: HIV infected youths will have impaired endothelial function compared to age matched healthy controls. Specific Aim 2: To determine risk factors of endothelial dysfunction by evaluating: 1) risk factors specific to HIV such as disease stage, cluster of differentiation 4 (CD4) count, HIV viral load, specific ART regimen, perinatally acquired versus behaviorally acquired infection; 2) markers of cardiovascular disease risk such as smoking, lipid levels, insulin resistance; 3) markers of inflammation and immune activation Hypothesis: Endothelial dysfunction will correlate with advanced HIV disease stage, use of protease inhibitors and worse traditional cardiovascular disease risk factors including lipids, insulin resistance, and smoking. Specific Aim 3: To assess whether endothelial function changes over a period of 24 weeks in HIV infected youths and controls. Hypothesis: Endothelial dysfunction will progress over time in HIV-infected children but not in healthy controls. Study Design This is a 24-week observational cohort study to gather preliminary data on the prevalence and risk factors for endothelial dysfunction in HIV-infected youths. Children enrolled will be between the ages of 8 and 30 years and either congenitally or behaviorally infected with HIV, on continuous ART for at least 6 months and with HIV-1 RNA <1,000 copies/mL. We will also enroll an age- and gender-matched group of healthy controls. A total of 50 HIV-infected children/young adults and 50 matched controls will be enrolled. Evaluations will be performed at two time points: baseline and week 24. At both visits, evaluations will be similar. We will collect demographic data and medical history including date of birth, sex, gender, CD4 cell count nadir, past and current ART and non-ART medication history, HIV stage based on the CDC guidelines, HIV diagnosis date and method of HIV acquisition, alcohol, smoking and drug habits, as well as family history of cardiovascular disease or diabetes. We will record clinical measurements including blood pressure, physical examination abnormalities, waist and hip circumferences and tanner stage. Subjects will undergo laboratory measurements of lipids levels and markers of insulin resistance in a fasting state (>8 hrs fast except for water and medications), as well as inflammation and immune activation markers (hsCRP, Interleukin 6 or IL-6, sCD14). HIV RNA and CD4 cell count will be collected from clinical records. Plasma and serum will be stored for possible future measurements of other inflammation and cardiovascular markers. We will perform endothelial function measurements by PAT as recommended by the manufacturer. Controls will be recruited from the community using Institutional Review Board (IRB)-approved flyers, as uninfected siblings or relatives of the HIV-infected patients, or from physician referrals.

Official Title
-----------------
Use of EndoPAT for Measurements of Endothelial Dysfunction in HIV Infected Children and Healthy Controls

Conditions
-----------------
HIV, Endothelial Dysfunction

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: For HIV+ group: age 8-30 years of age HIV infection On continuous ART for at least 6 months HIV-1 RNA < 1,000 copies/mL performed in the past 5 months For healthy controls: age and gender matched 1:1 to HIV-positive subjects absence of known HIV or other medical conditions that may affect systemic inflammation Not receiving or prescribed any regular chronic medications. Exclusion Criteria: - Active illness or regular medication Diabetes Known coronary artery disease Pregnancy and or lactation

Ages Eligible for Study
-----------------
Minimum Age: 8 Years
Maximum Age: 30 Years

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

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

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

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| HIV positive<br>people with HIV diagnosis | |
| Control (HIV negative)<br>people without HIV | |

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| endothelial function, as measured by endoPAT, between HIV-infected youth and matched healthy controls | Endothelial function will be measured using peripheral arterial tonometry. The device will record finger arterial pulsatile volume changes. The recordings will be performed with the patient in supine position with both hands at the same level. A blood pressure cuff will be placed on the upper arm (non-dominant); the probes will be placed on the finger of each hand (same finger on both hands) and continuing recording of blood volume responses from both hands will be initiated. After a period of stabilization, the blood pressure cuff on the study arm will be inflated to 60 mm Hg above systolic pressure for 5 min. The cuff will be deflated to induce reactive hyperemia and assess PAT. A reactive hyperemia index will be generated and is the post to pre occlusion PAT signal ratio in the occluded side normalized to the control side and corrected for baseline vascular tone. A normal index is >1.67 and abnormal is ≤ 1.67. | one year | 
| risk factors of endothelial dysfunction | To determine risk factors of endothelial dysfunction by evaluating: 1) risk factors specific to HIV such as disease stage, CD4 count, HIV viral load, specific ART regimen, perinatally acquired versus behaviorally acquired infection; 2) markers of cardiovascular disease risk such as smoking, lipid levels, insulin resistance; 3) markers of inflammation and immune activation | one year | 
| endothelial function changes over a period of 24 weeks in HIV infected youths and controls. |  | 1 year |