Blood Pressure Target for Patients with Hypertension and Diabetes

September 27, 2010

Lowering blood pressure below 130 mm Hg does not improve cardiovascular outcomes in patients with hypertension, diabetes, and coronary artery disease.

Decreasing blood pressure to levels advocated by hypertension guidelines does not improve cardiovascular outcomes in patients with hypertension, diabetes, and coronary artery disease (CAD).

According to the authors of a study published in JAMA back in July , although some hypertension guidelines “advocate treating systolic blood pressure (BP) to less than 130 mm Hg for patients with diabetes mellitus,” (see for example the National Kidney Foundation KDOQI Clinical Practice Guidelines and Clinical Practice Recommendations for Diabetes and Chronic Kidney Disease), there is little data showing the benefits of treating systolic blood pressure to less than 130 mm Hg in patients with hypertension, diabetes, and CAD. Accordingly, Rhonda M. Cooper-DeHoff, PharmD, MS, University of Florida, Gainesville, and colleagues examined whether patients with hypertension, diabetes, and CAD who lowered their systolic blood pressure to less than 130 mm Hg would “have a reduced risk of cardiovascular events compared with those who managed to keep their systolic BP within the range of at least 130 mm Hg to less than 140 mm Hg.”

They examined data from 6,400 participants in the International Verapamil SR-Trandolapril Study (INVEST) who were “at least 50 years old and had diabetes and CAD.”

A news release from JAMA said that these patients received treatment “with either a calcium antagonist or beta-blocker followed by angiotensin-converting enzyme inhibitor, a diuretic, or both to achieve systolic BP of less than 130 and diastolic BP of less than 85 mm Hg.” The researchers organized patients into three categories based on level of BP control; the “tight control” group included patients who maintained systolic BP at less than 130 mm Hg, the “usual control” group kept their systolic BP between 130 mm Hg and 139 mm Hg, and the “uncontrolled” group maintained systolic BP of 140 mm Hg or higher.

The primary outcome of this study included the occurrence of all-cause death, nonfatal myocardial infarction (heart attack), or nonfatal stroke. The news release noted that “primary outcome occurred in 12.7 percent (286 patients) of those in the tight-control group, 12.6 percent (249 patients) of the usual-control group, and 19.8 percent (431 patients) of the uncontrolled groups.” The adjusted risk of all-cause mortality was “significantly greater in the tight-control group (22.8 percent) than in the usual-control group (21.8 percent).”

The authors of the study wrote that this observational study showed for the first time that “decreasing systolic BP to lower than 130 mm Hg in patients with diabetes and CAD was not associated with further reduction in morbidity beyond that associated with systolic BP lower than 140 mm Hg.” In fact, these results demonstrated that decreasing systolic BP to lower than 130 mm Hg in this patient population was associated with” an increase in risk of all-cause mortality” that persisted over the long term.”

The authors concluded that “at this time, there is no compelling evidence to indicate that lowering systolic BP below 130 mm Hg is beneficial for patients with diabetes; thus, emphasis should be placed on maintaining systolic BP between 130 and 139 mm Hg while focusing on weight loss, healthful eating, and other manifestations of cardiovascular morbidity to further reduce long-term cardiovascular risk.”