Step-care more effective than Canadian guidelines in treating hypertension

　　奥兰多，2007年11月4日，根据2007AHA科学年会上公布的一项突破性的试验结果，一项简化阶段性治疗方法比指南指导下的治疗方式更能有效的降低高血压患者的血压水平。

　　STITCH试验（The Simplified Treatment Intervention to Control Hypertension）入选了加拿大Ontario 地区西南部的45个家庭医疗2,104例高血压患者。为了提高达到目标降压水平患者的百分比，研究者要观察这种治疗方式是否时能够比国家指南更简便的最佳降低血压方法。

　　“现存降压指导方针的复杂性也许是有效治疗的壁垒，”Ross D. Feldman谈到，“为了验证这个问题，我们进行了一项随机分组试验，各家庭医疗随机分为简化阶段性治疗组（STITCH-care）和指南治疗组。”

　　STITCH治疗包括四个步骤：1）初始期的ACEI/利尿剂或者血管紧张素受体阻滞剂/利尿剂联合治疗；2）增加联合治疗的剂量至最高耐受剂量；3）增加一种钙离子通道阻滞剂提高最高耐受剂量；4）增加一种非一线抗高血压药物。

　　在治疗指南中，内科医师学习了加拿大高血压教育项目的治疗指南，内科医生可以根据患者所患高血压的类型和患者其他疾病情况，从12种治疗方案中选择初期治疗的方案（非常类似于美国国家联合委员会指南给出的选择）。

　　血压达到目标水平的患者比例在STITCH-care组显著高于指南治疗组（65% vs. 53%），平均收缩压降低了23mmHg，显著高于指南治疗组的18mmHg。另外，舒张压在STITCH-care组和指南治疗组中分别降低了10mmHg、8mmHg，同样存在显著的统计学差异。

　　Feldman 说：“STITCH-care组的分配使血压达标率提高了至少20% ，我们相信采用简化的原则治疗高血压是可行的，可被家庭医生接受，并可提高血压控制率，‘阶段性’治疗的回归可能是治疗高血压的重要途径并且可参考用于一些慢性疾病的治疗。”

　　尽管指南看起来能够提供更加个体化的治疗，但是对于繁忙的内科医生来说，确定并记清众多患者的诸多治疗方案并非易事，容易张冠李戴。

Step-care more effective than Canadian guidelines in treating hypertension

ORLANDO, Nov.4 – A simplified, step-care protocol for treating high blood pressure was more effective than guidelines-based practice in helping people reduce their blood pressure, according to late- breaking clinical trial results presented at the American Heart Association’s Scientific Sessions 2007.

The Simplified Treatment Intervention to Control Hypertension (STITCH) trial included 2,104 patients with high blood pressure (hypertension) at 45 family practices in southwestern Ontario, Canada.  In order to increase the percentage of hypertensive people who reduce their blood pressure to “goal” levels, researchers wanted to see if there was a simpler way to direct treatment for hypertension than by following national guidelines for optimal management of blood pressure.

“The complexity of existing guidelines for managing hypertension could be a barrier to effective therapy,” said Ross D. Feldman, M.D., R.W. Gunton Professor of Therapeutics at the University of Western Ontario in London, Canada.“To examine this question, we conducted a cluster randomization trial.  Family practices were randomly assigned to implement a simplified step-care algorithm (STITCH-care) or guidelines-based care for managing hypertension.”

The STITCH algorithm consisted of four steps: 1) Initiate therapy with ACE-inhibitor/diuretic or angiotensin receptor blocker/diuretic combination; 2) Increase the dosage of this combination therapy to the highest tolerated dose; 3) Add a calcium channel blocker and increase to the highest tolerated dose; 4) Add one of the non-first line antihypertensive agents.

In the guidelines-care physicians learned about the national guidelines of the Canadian Hypertension Education Program, which has 12 options for initial therapy that physicians can choose from depending on the type of hypertension and the patient’s co-existing medical conditions (very similar to options in the U.S. Joint National Committee guidelines).

The proportion of patients who reduced blood pressure to the target level was significantly higher in the STITCH-care group (65 percent) compared with the guidelines-care group (53percent).  Average systolic blood pressure (the top number in a blood pressure measurement) was reduced by 23 mmHg in the STITCH-care arm, significantly more than the 18mmHg in the guidelines-care arm.In addition, diastolic blood pressure (the bottom number) was reduced by 10 mmHg in the STITCH-care patients and 8mmHg in the guidelines-care group, a difference that was also statistically significant.

“Assignment to the STITCH-care arm increased the chance of reaching the optimal blood pressure target by over 20 percent,” Feldman said.“We believe that use of a simplified algorithm to treat hypertension is implementable, accepted by family physicians and results in improved blood pressure control rates.This return to ‘step-care’ may be an important way forward for the treatment of hypertension and may be a paradigm for managing a range of chronic diseases.”

While these guidelines would seem to offer a more patient-centric approach, tailoring care to each individual, it’s possible the number of options is confusing to busy physicians with limited time to spend with each patient.

Support for this study was provided by Pfizer.