Are the Recommended Blood Pressure Goals in High‐Risk Patients Based on Outcome Data or Opinion?

Abstract

Treatment of hypertension to specific blood pressure (BP) goals is controversial, and the exact goal BP for different clinical populations at high risk for cardiovascular disease (CVD) is hotly debated. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) specifically recommended a goal BP of 130 ⁄80 mm Hg for patients with chronic kidney disease (CKD) or diabetes mellitus (DM). The national kidney foundation (Kidney Disease Outcomes Quality Initiative [KDOQI]) guidelines also recommend a goal BP of 130 ⁄80 mm Hg in patients with CKD and DM and a goal BP of 125 ⁄75 mm Hg in CKD patients with proteinuria >1000 mg ⁄d. More recent, the American Heart Association (AHA) and the European Society of Hypertension ⁄European Society of Cardiology recommended a goal BP of 130 ⁄80 mm Hg in all patients with coronary artery disease (CAD) or CAD risk equivalents, including patients with carotid artery disease, peripheral arterial disease, abdominal aortic aneurysm, and patients with high risk for CVD with a Framingham 10-year risk score >10%. In addition, the AHA also recommended a BP 120 ⁄80 mm Hg in patients with CAD and left ventricular dysfunction. The rationale behind these recommendations in patients with CKD is that these patients are considered to be the ‘‘highest-risk’’ group for CVD. Although patients with CKD have a many-fold increased risk of CVD, there has not been a controlled trial demonstrating superior CVD prevention by lowering BP to the recommended 130 ⁄80 mm Hg goal. So where does this recommendation come from? A recent meta-analysis was conducted to assess whether lower BP targets ( 135 ⁄85) are associated with reduction in mortality and morbidity as compared with standard BP targets of 140–160 ⁄ 90–100 mm Hg. Interestingly, no trials comparing different systolic BP (SBP) targets were found. Seven trials (22,089 patients) comparing different diastolic BP (DBP) targets were included. Primary outcomes were myocardial infarction, stroke, congestive heart failure, major cardiovascular (CV) events, and endstage renal disease. Secondary outcomes were achieved mean SBP and DBP and withdrawals due to adverse effects. Despite a greater achieved reduction in SBP and DBP, the ‘‘lower targets’’ did not improve mortality, myocardial infarction, stroke, congestive heart failure, or end-stage renal disease. Specifically a sensitivity analysis in diabetic patients and in patients with CKD also did not show a reduction in any of the mortality and morbidity outcomes with lower targets as compared with standard targets. Treating patients to lower BP targets does not reduce mortality or morbidity. The Action to Control Cardiovascular Risk in Diabetes (ACCORD) study of 4733 diabetics with hypertension echoes the findings of this meta-analysis. Despite a difference of 14 mm Hg in SBP, the primary end points (non-fatal myocardial infarction, nonfatal stroke, or CV death) were not improved by more aggressive BP reduction after nearly 5 years of follow-up. Stroke risk was, however, significantly lower in the intensive BP group (P=.01). Critics of this study have pointed out that although From the Department of Medicine, Hypertension Program, University of Pennsylvania School of Medicine, Philadelphia, PA Address for correspondence: Debbie L. Cohen, MD, Renal Division, University of Pennsylvania School of Medicine, 210 White Building, Philadelphia, PA 19104 E-mail: cohendl@mail.med.upenn.edu