Ettinger B, Citron J T, Livermore B, Dolman L I
Department of Medicine, Kaiser Permanente Medical Centers, San Francisco, California 94115.
J Urol. 1988 Apr;139(4):679-84. doi: 10.1016/s0022-5347(17)42599-7.
We examined the effectiveness of chlorthalidone or magnesium hydroxide in the prevention of recurrent calcium oxalate kidney calculi. In a double-blind random allocation design daily dosages of 25 or 50 mg. chlorthalidone, 650 or 1,300 mg. magnesium hydroxide, or an identical placebo were administered. All groups showed significantly decreased calculous events compared to the pretreatment rates. During the trial 56.1 per cent fewer calculi than predicted developed in the placebo group (p less than 0.01), whereas the groups receiving low and high dosage magnesium hydroxide showed 73.9 and 62.3 per cent fewer calculi, respectively (p less than 0.001 and less than 0.01, respectively). Chlorthalidone treatment resulted in a 90.1 per cent decrease from predicted rates and both dosages yielded similar results. When the treatments were compared chlorthalidone was significantly better than the placebo or magnesium hydroxide (p less than 0.01). The large decreases in calculous events seen when placebo or ineffective therapy was given underscore the positive treatment bias that occurs when historical controls are used and they demonstrate the need for proper experimental design.
我们研究了氯噻酮或氢氧化镁在预防复发性草酸钙肾结石方面的有效性。采用双盲随机分配设计，给予每日剂量为25或50毫克的氯噻酮、650或1300毫克的氢氧化镁，或相同的安慰剂。与治疗前的发生率相比，所有组的结石事件均显著减少。在试验期间，安慰剂组的结石形成比预测的少56.1%（p<0.01），而接受低剂量和高剂量氢氧化镁的组分别比预测的少73.9%和62.3%（p分别<0.001和<0.01）。氯噻酮治疗使结石形成比预测率降低了90.1%，两种剂量的效果相似。当对这些治疗进行比较时，氯噻酮明显优于安慰剂或氢氧化镁（p<0.01）。给予安慰剂或无效治疗时结石事件大幅减少，这突出了使用历史对照时出现的阳性治疗偏倚，也表明了进行适当实验设计的必要性。
