Evaluating the Relationship Between Inflammation, Genetics, and Stress in the Development of High Blood Pressure

Study Overview
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Brief Summary
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High blood pressure affects nearly one third of all individuals in the United States. If left untreated, it can lead to stroke, heart failure, heart attack, kidney failure, or blindness. For many people, the exact cause of high blood pressure is unknown, but it is believed that both genetic and environmental factors contribute to the development of the condition. The purpose of this study is to examine the importance of genetics, inflammation, and stress on the development of high blood pressure.

Detailed Description
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High blood pressure is a complex condition that can be caused by many factors, including obesity, diet, genetics, or stress. Maintaining a healthy balance of sodium in the body is important for adequate blood pressure control. Some individuals experience sustained high blood pressure during periods of extended stress, combined with the inability to excrete enough sodium through urine to re-establish normal blood pressure levels. This type of stress-induced high blood pressure is related to interleukin-6 (IL-6), a protein that stimulates inflammation and immune responses. To determine the interaction between stress, inflammation, and genetics, this study will examine the role of IL-6 in regulating sodium levels and blood pressure in individuals undergoing stress. This information will be useful in determining new ways to evaluate risk factors for high blood pressure. This study will examine previously collected DNA samples from young adults who participated in prior genetic studies. There will be no study visits for participants. IL-6, IL-6R, glycoprotein 130 (gp130), and C-reactive protein (CRP) genes will be analyzed in all samples; changes in plasma levels of IL-6 and CRP in response to stress will be examined in selected samples. The parents of participants will be asked to provide cheek swabs for additional DNA analysis.

Official Title
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Inflammatory Factors, Genes and Stress Induced Pressure Natriuresis in Youth

Conditions
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Hypertension

Intervention / Treatment
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* Behavioral: Induced Stress
* Procedure: Buccal Swab


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participated in two previous NIH funded studies HL073260, HL077230 Biological parents willing to participate in the study African American or European origins Exclusion Criteria: Non-biological parents

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 19 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Children<br>Children age 15-19, self reported as African American of European Origin, healthy non-smoker, with normal blood pressure, exposed to an activity to that results in induced stress | Behavioral: Induced Stress<br>* Participation in an active coping task by playing a video game against another participant.<br>|
| Parents<br>Collection of buccal swab Parent of participants in the Children Arm | Procedure: Buccal Swab<br>* One Buccal swab collected from each parent<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Urinary Sodium Excretion (UNaV) | The value of Stress induced UNaV as determined by delta UNaV = stress UNaV - baseline UNaV. | Baseline and 4 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Effect of Change in Stress Induced IL-6 on Systolic Blood Pressure | Stress induced systolic blood pressure (SBP) data generated from two previous studies was collected. In the previous studies, systolic blood pressures were measured before and after completing a video game challenge. Stress induced SBP is defined as delta SBP = stress SBP - baseline SBP. | baseline and 4 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Blood Pressure, High, Stress, Inflammation