The ACCORD Blood Pressure Study: What Target for High-Risk Diabetic Patients?

The ACCORD Blood Pressure Study: What Target for High-Risk Diabetic Patients?
Achieving systolic blood pressure levels lower than 140 mm Hg does not prevent adverse cardiovascular events.
In epidemiological studies, lower blood pressure (BP) is associated with lower cardiovascular risk. But, in high-risk patients, would achieving blood pressure targets lower than those recommended in guidelines reduce risk further? Researchers evaluated whether a blood pressure target of <120 mm Hg in patients with type 2 diabetes would lower risk for adverse cardiovascular events.
A total of 4733 high-risk diabetic patients (mean age, 62; 48% women; glycosylated hemoglobin, 7.5%; systolic blood pressure [SBP], 130–180 mm Hg) who were taking 3 antihypertensive medications and had no proteinuria were enrolled. Patients were assigned to intensive BP control (target SBP, <120 mm Hg) or standard BP control (target SBP, <140 mm Hg). Mean follow-up was 4.7 years. Mean systolic and diastolic BP levels at baseline were 139 mm Hg and 76 mm Hg, respectively. At 1 year, average SBP levels were 119 mm Hg in the intensive-care group and 134 mm Hg in the standard-care group. The lower BP in the intensive-care group was achieved by prescribing more drugs in every antihypertensive class; the mean number of medications at 1 year was 3.4 in the intensive group and 2.1 in the standard-care group.
At 5 years, the rate of adverse cardiovascular events was 1.9% per year in the intensive-care group and in 2.1% per year in the standard-care group (hazard ratio, 0.88; P=0.2). Death rates were similar in the two groups. No secondary analysis was strongly positive, except that stroke incidence was significantly lower in the intensive-care group than in the standard-care group (0.32% vs. 0.53%). The intensive-care group had a higher rate of serious adverse events, with more decrements in renal function and more episodes of syncope, bradycardia, hyperkalemia, and hypotension. Overall, 3.3% of the intensive-care group had adverse events attributed to the medications, compared with 1.3% of the standard-care group.
Comment: This study indicates that intensive blood pressure control (to levels lower than those currently recommended by guidelines) should not be used in high-risk diabetic patients. The findings leave open the question about what the optimal BP target is for these patients. The overall event rate was low in both groups, showing what can be achieved with good contemporary treatment strategies.
— Harlan M. Krumholz, MD, SM
Published in Journal Watch Cardiology March 14, 2010
Citation(s):
The ACCORD Study Group. Effects of intensive blood-pressure control in type 2 diabetes mellitus. N Engl J Med 2010 Mar 14; [e-pub ahead of print]. (http://dx.doi.org/10.1056/NEJMoa1001286)