HYDROCHLOROTHIAZIDE AND CHLORTHALIDONE ON BLOOD PRESSURES

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。来自降压降脂预防心脏病发作试验（ALLHAT）的最新证据表明，与血管紧张素转换酶抑制剂和钙通道阻滞剂等新型降压药相比，噻嗪类利尿剂的初始治疗可显著降低卒中和冠心病事件的发生率。氯噻酮是ALLHAT中使用的噻嗪类利尿剂，传统上是许多具有里程碑意义的高血压临床试验中使用的利尿剂。然而，氢氯噻嗪（HCTZ）是在美国临床实践中典型使用的噻嗪类利尿剂。虽然大多数临床医生认为HCTZ和氯噻酮在临床上是可互换的，但缺乏将这些药物直接相互比较的数据。这是一项为期8周的开放标签交叉试验，比较HCTZ与氯噻酮在办公室血压和动态血压方面的降压效果。患有原发性高血压并符合纳入标准的男性和女性将从爱荷华大学家庭护理中心的两个初级保健实践中招募。在2-4周的洗脱期后，患者将返回办公室进行每周一次的血压测量，然后患者将进行基线动态血压监测，并随机分配到HCTZ 25mg /d或氯噻酮12.5 mg/d。患者将每两周返回办公室进行血压测量，和/或实验室测量，和/或剂量滴定（氯噻酮和HCTZ的最大剂量分别为25mg和50mg）。第8周再次进行动态血压监测。在完成第一组研究后，患者将再次经历第二个2-4周的洗脱期，并进入与第一组相同但使用相反药物的研究的另一组。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Recent evidence from the Antihypertensive and Lipid-Lowering to Prevent Heart Attack Trial (ALLHAT) suggests initial therapy with a thiazide-type diuretic confers significantly higher reductions in stroke and coronary heart disease events compared to newer antihypertensive agents such as angiotensin-converting enzyme inhibitors and calcium channel blockers. Chlorthalidone, the thiazide-type diuretic utilized in ALLHAT, has traditionally been the diuretic utilized in many of the landmark clinical trials in hypertension. However, hydrochlorothiazide (HCTZ) is the thiazide diuretic typically used in clinical practice in the United States. Although most clinicians assume HCTZ and chlorthalidone are clinically interchangeable, there is a lack of data comparing these agents directly to one another. This is an 8-week, open-label, crossover trial comparing the antihypertensive effects of HCTZ versus chlorthalidone on both office-based and ambulatory blood pressures. Men and women with essential hypertension and meeting inclusion criteria will be recruited from two primary care practices at the University of Iowa Family Care Center. After a 2-4 week washout period during which time patients will return for weekly office blood pressure measurements, patients will then undergo a baseline ambulatory blood pressure monitoring session and be randomized to either HCTZ 25 mg/d or chlorthalidone 12.5 mg/d. Patients will return biweekly for office blood pressure measurements, and/or laboratory measurements, and/or dosage titration (to a max dose of 25 mg for chlorthalidone and 50 mg of HCTZ). Ambulatory blood pressure monitoring will be repeated at week 8. Following completion of the first arm of the study, patients will again undergo a second 2-4 week washout period and proceed into the opposite arm of the study which is identical to the first arm but with the opposite medication.