Cardiovascular Function and Postprandial Hypotension (PPH): Effect of an Oral Glucose Load on Cardiac Contractility, Cardiac Output, Diastolic Function and Endothelial Function - Relationship to Gastric Emptying
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 8
- 主要终点
- Change from baseline systolic blood pressure over time.
研究概览
简要总结
To determine whether the changes in blood pressure (BP) which occur following meals in normal people and patients who have substantial falls in BP after a meal postprandial hypotension (PPH)) are associated with changes in cardiac function. Eligible subjects who have been previously diagnosed with PPH will report to the Queen Elizabeth Hospital, on two occasions, following an overnight fast. Subjects will be cannulated and have a BP cuff placed around their upper arm. Following this, subjects will ingest either a drink containing 75 grams of glucose and 150mg of a C13 Acetate (which is metabolised and excreted in the breath, enabling noninvasive measurements of gastric emptying), made up to 300mL water, or on the other study day, 300mL water alone. The order of the study days will be randomised. Following the drink, for 3 hours, measurements will be taken at regular intervals of BP, heart rate, breath samples (on the study day with the Acetate only), blood samples (for measurement of blood glucose and gut hormones) and transthoracic echocardiography (TTE) (for assessment of end systolic and diastolic cardiac volume, cardiac output, cardiac contractility and diastolic function). After the 3 hours of measurements, the cannula will be removed and subjects will be offered lunch prior to leaving the department. Following lunch, on one study day, subjects will have their autonomic nerve function tested noninvasively, using an ECG.
详细描述
Subjects who meet the inclusion criteria will be required to attend the Queen Elizabeth Hospital, on two separate occasions, at 08:30h following an overnight fast (solids for 14 hours and liquids for 12 hours) and abstaining from smoking for 12 hours prior to the study day. The order of the study days will be randomized using the online Random Integer Set Generator program (RANDOM.ORG).
On each of the study days, subjects will be seated and have an intravenous cannula inserted into an antecubital vein in the arm for blood sampling and an automated blood pressure (BP) cuff (DINAMAP ProCare 100, GE Medical Systems, Milwaukee, WI, USA) placed around the opposite arm for measurements of BP (systolic and diastolic) and heart rate (HR).
After a 15-minute rest period, subjects will consume a drink consisting of either 75g glucose and 150 mg of 13C-acetate made up to 300 ml with water, or 300 ml water, within 3 minutes (t = -3 - 0 minutes).
BP and HR will be measured at 3 minute intervals during the 30-minute rest period prior to the drink (i.e. t = -30 - 0 minutes) and at 3 minute intervals from t = 0 - 180 minutes.
Blood samples (~ 18ml) will be taken prior (t = -3 minutes) to the drink and then at t = 30, 60, 90, 120 and 180 minutes for the subsequent measurement of blood glucose, serum insulin and incretin hormones. Samples will be stored at -70°C until analysed. Blood glucose will be determined immediately using a portable glucometer (Medisense Companion 2 meter, Medisense Inc, Waltham, USA).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 65 Years 至 85 Years（Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Control subjects: subjects from this group will be healthy, with normal BMI. PPH subjects: Patients who have been diagnosed with PPH (defined as a fall in systolic blood pressure (BP) of > 20mmHg within 2 hours of a meal).
排除标准
- •No history of severe respiratory, cardiovascular, hepatic and/or renal disease, diabetes, are not taking any medication with effects on blood pressure or gastrointestinal function, have not donated blood for the past 12 weeks or been involved in any research projects for the past 3 months.
结局指标
主要结局
Change from baseline systolic blood pressure over time.
时间窗: time= 0 - 120 min
time= 0 min is defined as the consumption of either the experimental or control drink, i.e. outcome will be assessed for 2 hours.
次要结局
- Change from baseline cardiac output as assessed by echocardiography, over time.(time= 0 - 120 min)
- Change from baseline stroke volume as assessed by echocardiography, over time.(time= 0 - 120 min)
- Change from baseline ejection fraction as assessed by echocardiography, over time.(time= 0 - 120 min)
研究者
Karen Jones
Professor
Royal Adelaide Hospital