Neurovascular Control of Renal Blood Flow During Exercise in Older African American Adults
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 入组人数
- 12
- 试验地点
- 1
- 主要终点
- Change in renal vascular resistance during acute exercise
研究概览
简要总结
The goal of this preliminary study is to learn if healthy older African American (AA) adults have a larger change in their kidney blood flow during exercise compared to White (W) adults. The main questions that this study aims to answer are:
- Do healthy older AA adults have a larger decrease in kidney blood flow during exercise compared to W adults?
- Do healthy older AA adults have a larger decrease in kidney blood flow during other types of stress compared to W adults?
During one visit in the research lab, participants will:
- Perform cycling exercise while lying down
- Undergo a cold hand test
- Perform a mental math test
Completing this preliminary study will help researchers to understand more about why many AA adults have heart and kidney problems, so future research can study ways to reduce the number of AA adults who have these health issues.
详细描述
Racial disparities exist in the development of high blood pressure and heart and kidney disease. Over the last 25 years, African American (AA) adults have had the greatest prevalence of high blood pressure compared to any other racial identity group in the United States. In 2015, ~100,000 AA adults died from heart disease, accounting for one-third of all deaths in this population. AA adults also have a 2-3-times higher lifetime risk for developing end-stage kidney disease compared to White (W) adults. Further, advanced age is one of the most significant risk factors for developing high blood pressure, heart disease, and kidney disease. In 2013-2014, ~29% of deaths of adults aged 65 years or older were caused by heart disease, the leading cause of death in this population.
Elevated sympathetic nervous system activity is associated with increased incidence of heart and kidney disease. Physical activity, such as exercise, acutely increases sympathetic nervous system activity, notably directed towards the kidneys, resulting in reflex narrowing of small blood vessels inside the kidneys. This response reduces blood flow to the kidneys to deliver greater blood flow to the active skeletal muscles. Most of the research studies in this area have involved participant groups who were wholly or predominantly of W racial identity, with smaller proportions of individuals of other racial identities. This underrepresentation of non-W participants, including AA adults, has occurred despite the known health disparities such as the greater incidence of high blood pressure and heart disease and kidney disease experienced by these populations.
A larger decrease in kidney blood flow during exercise has been observed in patients with heart failure and peripheral arterial disease compared to healthy adults. However, it is not known whether the decrease in kidney blood flow during exercise is larger in healthy older AA adults compared to other racial identity groups. Given the greater level of chronic psychological stress often experienced by AA adults due to systemic racism and social and environmental factors, the associated cumulative negative impact on cardiovascular health could underlie a physiological difference observed between AA and W adults. Therefore, it is hypothesized that healthy older AA adults will exhibit a larger decrease in kidney blood flow during exercise compared to W adults. This greater response in older AA adults could be a significant factor contributing to the higher rates of heart and kidney disease in this population given the negative effect that this larger response could have over time, highlighting the clinical significance of this area.
The goal of this project is to collect preliminary data regarding the kidney blood flow response to exercise in healthy older AA compared to W adults. This will be achieved through the innovative use of Doppler ultrasound to noninvasively measure kidney blood flow in real time during cycling exercise in 6 healthy older AA adults and 6 healthy older W adults. The preliminary data collected in this project will be used to strengthen future proposals to secure external funding to complete this project on a larger scale. Findings from a larger-scale project will have important implications for developing preventative strategies to reduce the elevated risk of developing heart and kidney disease in the AA population.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 55 Years 至 79 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Self-report as either African American or White racial identity
- •Born in United States
- •Both biological parents identify as same racial identity as participant
- •Recreationally active (participating in physical activity for at least 20 minutes per day, at least three times per week, but not training for competitive events)
- •Fluent in English
排除标准
- •Hispanic or Latino
- •Females who are pregnant or lactating
- •Cardiovascular or renal disease
- •Hypertension (blood pressure of more than or equal to 130/80 mmHg)
- •Obesity (body mass index of more than or equal to 30 kg/m2)
- •Smoker/Tobacco user
- •Acute medical conditions
- •Taking prescribed cardiovascular, antihypertensive, or renal medications
研究组 & 干预措施
African American Adults
African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Acute exercise (Other)
African American Adults
African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Cold pressor test (Other)
African American Adults
African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Mental stress test (Other)
White Adults
White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Acute exercise (Other)
White Adults
White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Cold pressor test (Other)
White Adults
White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
干预措施: Mental stress test (Other)
结局指标
主要结局
Change in renal vascular resistance during acute exercise
时间窗: Pre-acute exercise and during 5 minutes of steady-state exercise
For the acute exercise intervention, the percent change from pre-acute exercise to during steady-state exercise will be assessed.
Change in renal vascular resistance during cold pressor test
时间窗: Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test
For the cold pressor test intervention, the percent change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in renal vascular resistance during mental stress test
时间窗: Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test
For the mental stress test intervention, the percent change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
次要结局
- Change in renal blood flow velocity during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in mean arterial blood pressure during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in systolic blood pressure during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in diastolic blood pressure during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in heart rate during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in cardiac output during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in stroke volume during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in total peripheral resistance during acute exercise(Pre-acute exercise and during 5 minutes of steady-state exercise)
- Change in renal blood flow velocity during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in mean arterial blood pressure during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in systolic blood pressure during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in diastolic blood pressure during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in heart rate during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in cardiac output during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in stroke volume during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in total peripheral resistance during cold pressor test(Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test)
- Change in renal blood flow velocity during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in mean arterial blood pressure during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in systolic blood pressure during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in diastolic blood pressure during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in heart rate during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in cardiac output during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in stroke volume during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
- Change in total peripheral resistance during mental stress test(Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test)
研究者
Rachel Drew
Associate Professor
University of Massachusetts, Boston