Pathophysiology of postprandial hypotension in the elderly - role of "gastric" and "small intestinal" mechanisms

老年人餐后低血压的病理生理学——“胃”和“小肠”机制的作用

• 批准号: nhmrc : 453650
• 负责人: Prof Christine Feinle-Bisset
• 金额: $ 31.42万
• 依托单位: The University of Adelaide
• 依托单位国家: 澳大利亚
• 项目类别: NHMRC Project Grants
• 财政年份: 2007
• 资助国家: 澳大利亚
• 起止时间: 2007-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/pathophysiology-postprandial-hypotension-intestinal-mechanisms/95379
• 关键词: Pathophysiology; postprandial; hypotension; elderly; role

A fall in blood pressure after a meal (known as postprandial hypotension) is an important clinical problem, particularly in the elderly, occurring in ~50% of nursing home residents and ~30% of healthy older subjects. Postprandial hypotension is associated with a substantial increase in the incidence of falls, stroke, as well as mortality. The mechanisms responsible for the fall in blood pressure after a meal are not well understood, although changes in gastrointestinal blood flow and the release of gut hormones, have been implicated. While ingestion of carbohydrate, particularly glucose, has been reported to decrease blood pressure most potently, there is inadequate and conflicting information about the effects of other nutrients such as fat and protein. Current therapies are less than optimal. Studies by our research group have established that the fall in blood pressure in response to meals is related to the rate at which nutrients enter the small intestine ie the fall in blood pressure is greater when the stomach empties more quickly. In contrast, gastric distension reduces the fall in blood pressure. Hence, treatment could be directed at facilitating gastric distension and-or slowing the rate of nutrient delivery into the small intestine. Our previous studies have not included any assessment of changes in blood flow to the gut after meals, or of the interaction between gastric distension and small intestinal mechanisms, and have involved healthy older subjects and patients with type 2 (non-insulin dependent) diabetes rather than individuals with known postprandial hypotension. We now have the capacity to measure blood flow in the gut with ultrasound. The studies proposed in the current application represent a logical development from our previous work and have important implications for the management of postprandial hypotension.

餐后血压下降（称为餐后低血压）是一个重要的临床问题，尤其是老年人，约 50% 的疗养院居民和约 30% 的健康老年受试者发生这种情况。餐后低血压与跌倒、中风和死亡率的发生率大幅增加有关。尽管胃肠道血流的变化和肠道激素的释放与餐后血压下降的机制有关，但尚不清楚。虽然据报道摄入碳水化合物，特别是葡萄糖，可以最有效地降低血压，但关于脂肪和蛋白质等其他营养素的影响的信息不充分且相互矛盾。目前的治疗方法并非最佳。我们研究小组的研究已经证实，进餐后血压的下降与营养物质进入小肠的速度有关，即当胃排空得越快时，血压的下降幅度就越大。相反，胃扩张会降低血压下降。因此，治疗可以旨在促进胃扩张和/或减慢营养物质输送到小肠的速度。我们之前的研究并未包括对餐后肠道血流变化或胃扩张与小肠机制之间相互作用的任何评估，并且涉及健康老年受试者和 2 型（非胰岛素依赖型）糖尿病患者，而不是已知餐后低血压的个体。我们现在有能力用超声波测量肠道内的血流量。本申请中提出的研究代表了我们之前工作的逻辑发展，对餐后低血压的治疗具有重要意义。