Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 453

Blood pressure can decrease markedly after meals in the elderly, and this represents an important but often under‐recognised clinical problem predisposing to syncope and falls.⁵⁹ Older people with type 2 diabetes are at particular risk, probably because of the associated autonomic neuropathy. Postprandial hypotension can, in the broadest sense, be regarded as a gastrointestinal disorder since the postprandial decline in blood pressure is related to the regulation of splanchnic blood flow and the release of gastrointestinal peptide hormones and can be attenuated by administration of the somatostatin analogue, octreotide. Amongst the macronutrients, both carbohydrate and fat contribute to the fall in blood pressure. After oral or small‐intestinal administration of glucose, the magnitude of the fall in blood pressure is related to the rate at which glucose enters the small intestine. Dietary and pharmacologic approaches which slow gastric emptying (e.g. GLP‐1 receptor agonists such as lixisenatide⁶⁰) and small‐intestinal carbohydrate absorption (e.g. acarbose) may prove to be effective in the treatment of postprandial hypotension, while distending the stomach (e.g. by drinking a glass of water) can attenuate the postprandial fall in blood pressure. There is limited evidence for the use of caffeine, a combination of denopamine (a beta 1 agonist) with midodrine (an alpha 1 agonist), and withdrawal of diuretic therapy for the prevention of postprandial hypotension.⁵⁹