Intensive Blood Pressure and Combination Lipid Therapies Do Not Reduce Combined Cardiovascular Events in Adults with Diabetes
Lowering blood pressure to below recommended levels and treating blood lipids with combination drug therapy failed to significantly reduce cardiovascular disease (CVD) events in adults with type 2 diabetes, according to new results from the landmark Action to Control Cardiovascular Risk in Diabetes (ACCORD) clinical trial.
The ACCORD trial is one of the largest studies ever conducted in adults with type 2 diabetes with an especially high risk of CVD events, such as heart attack, stroke, or death from CVD. The multicenter clinical trial tested three strategies to lower the risk of major CVD events: intensive control of blood glucose, also called blood sugar; intensive control of blood pressure; and treatment of multiple blood lipids. The study's primary sponsor was the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH). The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) also provided support for the study.
ACCORD researchers from 77 medical centers in the United States and Canada studied more than 10,000 participants between the ages of 40 and 79 who had type 2 diabetes for an average of 10 years. The participants also had pre-existing CVD, evidence of subclinical CVD, or at least two CVD risk factors. All the participants were enrolled in the ACCORD blood glucose treatment clinical trial and maintained good control of blood glucose levels during the study. In addition, participants were enrolled in either the blood pressure trial or the lipid trial and were treated and followed for an average of about 5 years.
Results of the ACCORD blood glucose clinical trial were reported in 2008. That trial found that intensively lowering blood glucose to near-normal levels brought a higher risk of death for participants than standard blood glucose control. For more information, see "New Analysis of Data from the ACCORD Blood Glucose Trial."
The results of the blood pressure and lipid trials appeared in the March 14, 2010, online edition of The New England Journal of Medicine.
In the blood pressure trial, researchers randomly assigned more than 4,700 participants with elevated blood pressure to a target systolic blood pressure of either below 140 millimeters of mercury (mmHg)-the standard group-or a normal level of below 120 mmHg-the intensive group. A variety of medications were used to reach blood pressure goals. The study found that lowering blood pressure to normal levels does not significantly reduce the risk of CVD events overall, although it may reduce the risk of stroke. More intensive blood pressure control was associated with a higher risk of serious adverse events.
In the lipid trial, researchers compared the cardiovascular effects of a statin (simvastatin) with combination therapy of a statin and a fibrate (fenofibrate) in more than 5,500 par-ticipants. Both statins and fibrates are used to treat abnormal levels of blood lipids. Statins lower low-density lipoprotein (LDL), or "bad," cholesterol and are proven to lower CVD risk in people with diabetes. Fibrates primarily lower fats in the blood known as triglycerides and raise high-density lipoprotein (HDL), or "good," cholesterol. High triglycerides and low HDL levels are common in people with diabetes.
Combination therapy appeared to be safe, but it did not lower the risk of heart attack, stroke, or death from CVD more than statins alone. Henry Ginsberg, M.D., of Columbia University, lead author of the lipid trial, said, "Although our analysis suggests that certain patients may benefit from combination therapy, this study provides important information that should spare many people with diabetes unneeded therapy with fibrates."
"ACCORD provides important evidence to help guide treatment recommendations for adults with type 2 diabetes who have had a heart attack or stroke or who are otherwise at especially high risk for cardiovascular disease," said NHLBI Acting Director Susan B. Shurin, M.D.
More information about research projects funded by the NIH can be found by using the Research Portfolio Online Reporting Tools (RePORT) Expenditures and Results (RePORTER) tool located at www.projectreporter.nih.gov/reporter.cfm.
The NIDDK has easy-to-read booklets and fact sheets about diabetes. For more information or to obtain copies, visit www.diabetes.niddk.nih.gov.
NIH Publication No. 10-4562
Page last updated: December 5, 2011