The Natriuretic Peptide System in African-Americans.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 60
- 试验地点
- 2
- 主要终点
- The difference in circulating NT-proANP levels in response to low and high dietary salt.
研究概览
简要总结
This study aims to assess the natriuretic peptide response to dietary salt loading in African-American individuals compared with white individuals.
详细描述
High blood pressure, or hypertension, is a major cause of heart disease, heart failure, and stroke. Natriuretic peptides are cardiac derived hormones that may protect against hypertension. The classical actions of the natriuretic peptides include natriuresis, vasodilation, and inhibition of the renin-angiotensin-aldosterone system (RAAS), which support a key role for these hormones in blood pressure regulation.
Race based differences exist in the risk and severity of hypertension and cardiovascular disease, with African-American individuals typically being at greater risk compared with white individuals. Nearly half of African-American adults have hypertension, compared with one-third of whites. Additionally, salt-sensitivity denotes the impaired ability to handle a salt load with resulting increases in blood pressure. It is estimated that 75% of hypertensive African-Americans exhibit salt-sensitivity, compared with 35% of hypertensive whites. Why this predilection towards salt-sensitivity exists, particularly among African-American individuals, is not well understood. Thus, establishing the origins of salt retention in African Americans has biologic, preventative, and therapeutic importance, and may provide insight regarding racial differences in cardiovascular risk.
The natriuretic peptide system is the principal counter-regulatory mechanism to salt retention. However, little is known regarding racial differences in the natriuretic peptide system. Recently, it was discovered that African-Americans have lower natriuretic peptide levels compared with whites, raising the possibility that African-Americans individuals can have a relative "natriuretic peptide deficiency" with reduced natriuretic peptide responses to salt loading. However, the prior studies were based on epidemiologic data with individuals on random salt backgrounds. This highlights the need for more detailed physiologic studies, under controlled salt conditions and with standardized assessment of the natriuretic peptide and RAAS and tissue sodium stores.
The aim of this study is to assess the natriuretic peptide response to dietary salt loading in African-American individuals compared with white individuals. This study will test the primary hypothesis that compared with whites, African-American individuals have blunted natriuretic peptide responses to dietary salt loading.
Secondary hypotheses include:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Health Services Research
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 55 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •age between 18 and 55 years
- •BMI between 18 and <25 kg/m2
- •normotensive or pre-hypertensive
- •willing to adhere to study diets
排除标准
- •prevalent cardiovascular disease or use of medications for cardiovascular disease
- •Current or prior history of hypertension or use of blood pressure lowering medications
- •Current or prior history of diabetes mellitus or use of anti-diabetic medications
- •Prevalent renal disease (eGFR < 60 ml/min/1.73m2), abnormal serum sodium or potassium
- •Current or prior smoker
- •Current pregnancy
- •Current steroid use
- •Contraindications to MRI
结局指标
主要结局
The difference in circulating NT-proANP levels in response to low and high dietary salt.
时间窗: 4 years
次要结局
- Tissue sodium content(4 years)
- Blood pressure(4 years)
- Salt-sensitive hypertension(4 years)
- Urinary sodium excretion(4 years)
- Myocardial early relaxation velocities(4 years)
- Plasma renin(4 years)
- Serum aldosterone(4 years)
研究者
Deepak Gupta
Principal Investigator
Vanderbilt University