Shibao Cyndya, Gamboa Alfredo, Diedrich Andre, Dossett Cynthia, Choi Leena, Farley Ginnie, Biaggioni Italo
Department of Medicine, Division of Clinical Pharmacology and the Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, TN 37212, USA.
Hypertension. 2007 Jul;50(1):54-61. doi: 10.1161/HYPERTENSIONAHA.107.091355. Epub 2007 May 21.
Postprandial hypotension is an important clinical condition that predisposes to syncope, falls, angina, and cerebrovascular events. The magnitude of the fall in blood pressure after meals depends on enteric glucose availability. We hypothesized that acarbose, an alpha-glucosidase inhibitor that decreases glucose absorption in the small intestine, would attenuate postprandial hypotension. Acarbose or placebo was given 20 minutes before a standardized meal in 13 patients with postprandial hypotension in the setting of autonomic failure (age: 65+/-2.64 years; body mass index: 25+/-1.08 kg/m(2); supine plasma norepinephrine: 110+/-26.6 pg/mL). Four patients were studied in a single-blind protocol and 9 patients in a double-blind, randomized, crossover fashion. Patients were studied supine, and blood pressure, heart rate, and neuroendocrine parameters were obtained at baseline and for 90 minutes after meal intake. After adjusting for potential confounders, acarbose significantly attenuated the postprandial fall in systolic and diastolic blood pressures by 17 mm Hg (95% CI: 7 to 28; P=0.003) and 9 mm Hg (95% CI: 5 to 14; P=0.001), respectively. Furthermore, acarbose effectively reduced plasma levels of insulin, a known vasodilator, by 11 microU/mL (95% CI: 5 to 18; P=0.001) compared with placebo. After adjusting for insulin levels, the attenuation of postprandial hypotension by acarbose remained significant, indicating that additional mechanisms contribute to this effect. In conclusion, 100 mg of acarbose successfully improved postprandial hypotension in patients with severe autonomic failure. This effect is not explained solely by a reduction in insulin levels.
餐后低血压是一种重要的临床病症，易引发晕厥、跌倒、心绞痛和脑血管事件。餐后血压下降的幅度取决于肠道内葡萄糖的可利用性。我们推测，阿卡波糖这种可减少小肠葡萄糖吸收的α-葡萄糖苷酶抑制剂，会减轻餐后低血压。在13例自主神经功能衰竭导致餐后低血压的患者（年龄：65±2.64岁；体重指数：25±1.08kg/m²；仰卧位血浆去甲肾上腺素：110±26.6pg/mL）中，在标准化进餐前20分钟给予阿卡波糖或安慰剂。4例患者采用单盲方案进行研究，9例患者采用双盲、随机、交叉方式进行研究。患者仰卧位接受研究，在基线以及进餐摄入后90分钟获取血压、心率和神经内分泌参数。在对潜在混杂因素进行校正后，阿卡波糖使收缩压和舒张压的餐后下降幅度分别显著减轻17mmHg（95%CI：7至28；P=0.003）和9mmHg（95%CI：5至14；P=0.001）。此外，与安慰剂相比，阿卡波糖使已知的血管扩张剂胰岛素的血浆水平有效降低了11μU/mL（95%CI：5至18；P=0.001）。在对胰岛素水平进行校正后，阿卡波糖对餐后低血压的减轻作用仍然显著，这表明还有其他机制促成了这种效应。总之，100mg阿卡波糖成功改善了严重自主神经功能衰竭患者的餐后低血压。这种效应并非仅由胰岛素水平降低所解释。
