Essential Hypertension Clinical Trials

Background: Childhood-onset essential hypertension (COEH) is high blood pressure that develops in children and teens. High blood pressure is a major risk factor for heart disease. COEH is more likely to be caused by changes in genes rather than by factors like stress or diet. Researchers want to learn more about how changes in genes relate to COEH. They hope to use that information to develop better treatments for children with high blood pressure. Objective: This natural history study will look for genes and gene changes that may lead to COEH. Eligibility: People aged 2 years and older with COEH or who had COEH when they were children. Healthy relatives of those with COEH are also needed. Design: Participants will have one clinic visit per year for up to 10 years. All participants will have a physical exam. They will provide samples of blood and urine. At their first visit, they will have a swab (like a Q-tip) rubbed between their gums and cheeks. They may agree to having a skin biopsy; a piece of skin about the size of a pencil eraser will be removed. Affected participants aged 2 to 17 years old will have additional tests: * They will have sensors placed on their skin to look at their blood vessels and see how blood is moving in their bodies. * They will lie or stand while a machine measures the amount of fat and muscle in their bodies. * They will have an ultrasound; a wand will be rubbed against their skin to take pictures of their kidneys. Other things are optional for all participants: * They may have photographs taken of their bodies. * They may have tests of their heart function. * They may have different types of imaging scans. Read Less

The prevalence of hypertension is greater in older women than men, while the blood pressure (BP) control rate is lower in older women in US. Uncontrolled hypertension is a major risk factor for cardiovascular morbidity/mortality. Despite standard therapy and adherence to optimal drug regimens, >50% of older hypertensive women still have inadequate BP control, and the control rate is further reduced with more aggressive BP targets recommended recently by the new Hypertension Guidelines. Thus, the effectiveness of drug treatment alone in the control of hypertension among older women is limited; hence, non-pharmacological approaches are also needed to help reduce BP in older hypertensive women. One adjuvant, non-pharmacological approach that offers promise in lowering BP is "heat therapy". Indeed, repeated whole-body heat exposure decreases BP in healthy humans. Whether this is also true after regional limb heating in hypertensive patients is unknown. The objectives of this research are to investigate the BP lowering effect of home-based lower leg heat therapy in older women with hypertension, and to examine the impact of this therapeutic modality on neural-vascular health in these patients. Aim 1 will test the hypothesis that chronic lower leg heat therapy combined with an antihypertensive drug is superior to drug treatment alone in lowering BP in older hypertensive women. We will randomly assign older hypertensive women to either an intervention group or a control group. Patients in the intervention group will perform 8 weeks of lower leg heat therapy via water immersion up to the knee in a circulated bath (water temperature 42°C, 4 times/week, 45 min/session), whereas patients in the control group will immerse their legs in a thermoneutral water bath (33°C) at the same frequency and duration. All patients will also receive a fixed dose of chlorthalidone (a diuretic, 25 mg orally daily). We will compare ambulatory BP, the BP control rate, and patient adherence and acceptability to treatment between the groups. Aim 2 will test the hypothesis that chronic lower leg heat therapy will improve nitric oxide bioavailability which can decrease sympathetic vasoconstriction and improve vascular function in older hypertensive women. We will use state-of-the-art techniques of microneurography, Doppler ultrasound, applanation tonometry, and cutaneous microdialysis to assess neural control, vasodilator function, and interstitial metabolites (i.e. nitrate and nitrite) indicative of basal nitric oxide bioavailability in all patients enrolled in Aim 1 before and after 8 weeks of heat therapy. Information obtained from this research project will guide evidence-based clinical practice. It is anticipated that our study may lead to revision of hypertension guidelines to incorporate home-based heat therapy as adjuvant to antihypertensive drug(s) for older women, as well as other patient populations. Read Less