Leite L P, Johnston B T, Just R J, Castell D O
Department of Medicine, Graduate Hospital, Philadelphia, Pennsylvania, USA.
Am J Gastroenterol. 1996 Aug;91(8):1527-31.
To identify patients with gastroesophageal reflux disease (GERD) who, despite omeprazole 20 mg b.i.d., demonstrate continued abnormal gastric acid secretion.
Eighty-eight patients with GERD completed ambulatory gastric and esophageal pH monitoring for persistent symptoms on omeprazole 20 mg b.i.d.. Seventeen (19%) demonstrated abnormal gastric acid secretion (percentage time gastric pH < 4 > 50%). The 17 omeprazole failures (OF) were compared with: 1) 19 randomly selected patients with GERD (also studied on omeprazole 20 mg b.i.d. and 2) 19 normal volunteers studied on both placebo and omeprazole 20 mg b.i.d.. Total time intragastric pH < 4, 24-hr gastric pH frequency distribution, and 15-min median pH values for the 6-h period after the evening omeprazole dose were compared.
Both the 24-hr frequency distribution for gastric pH and the 15-min median gastric pH profile for patients with GERD and volunteers on omeprazole 20 mg b.i.d. were almost identical. By contrast, gastric pH studies from the OF group receiving omeprazole 20 mg b.i.d. most closely resembled those of the normal subjects receiving placebo, with respect to these variables. Gastric pH monitoring in seven of the 17 OF patients while on omeprazole 80 mg/day demonstrated a significant decrease in the median percentage time gastric pH remained below 4 (32.8% on 80 mg/day vs 74.3% on 40 mg/day; p < 0.02).
There are individuals whose intragastric acidity persists despite conventional doses of omeprazole. Although the underlying mechanism remains unclear, the majority (six of seven) (87%) demonstrated improved gastric acid control when placed on high dose omeprazole, indicating that this is often a dose-dependent phenomenon.
识别尽管服用20毫克奥美拉唑每日两次但仍表现出持续胃酸分泌异常的胃食管反流病（GERD）患者。
88例GERD患者在服用20毫克奥美拉唑每日两次的情况下，因症状持续而完成了动态胃和食管pH监测。17例（19%）表现出胃酸分泌异常（胃pH值<4的时间百分比>50%）。将这17例奥美拉唑治疗失败（OF）的患者与以下两组进行比较：1）19例随机选择的GERD患者（也服用20毫克奥美拉唑每日两次进行研究）和2）19例正常志愿者，分别服用安慰剂和20毫克奥美拉唑每日两次进行研究。比较胃内pH值<4的总时间、24小时胃pH频率分布以及晚上服用奥美拉唑剂量后6小时期间的15分钟中位pH值。
GERD患者和服用20毫克奥美拉唑每日两次的志愿者的24小时胃pH频率分布以及15分钟中位胃pH曲线几乎相同。相比之下，就这些变量而言，接受20毫克奥美拉唑每日两次的OF组的胃pH研究与接受安慰剂的正常受试者最为相似。17例OF患者中有7例在服用80毫克/天奥美拉唑时进行胃pH监测，结果显示胃pH值保持在4以下的中位时间百分比显著下降（80毫克/天为32.8%，40毫克/天为74.3%；p<0.02）。
尽管服用常规剂量的奥美拉唑，仍有部分个体胃内酸度持续存在。虽然潜在机制尚不清楚，但大多数（七分之六）（87%）患者在服用高剂量奥美拉唑时胃酸控制得到改善，表明这通常是一种剂量依赖性现象。
