Intensive Blood Sugar Treatment Strategy in Clinical Trial of Diabetes and Cardiovascular Disease Changed

6 February 2008

The National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health has stopped one treatment within a large, ongoing North American clinical trial of diabetes and cardiovascular disease 18 months early due to safety concerns after review of available data. The study will continue, but it will be slightly modified.

The study is the ACCORD (Action to Control Cardiovascular Risk in Diabetes) study, which has enrolled 10,251 participants.

In the ACCORD study, adults with type 2 diabetes were recruited, especially people at higher risk for diabetes and stroke. These participants were divided into two groups and were treated in one of two ways (depending on which group they were in):

• lowering of blood glucose (sugar) below current recommendations, by intensive methods
  
• lowering of blood glucose (sugar) below current recommendations by a less-intensive method
  

After four years, the participants in the intensive method for lowering blood glucose levels had a slightly higher rate of death than the less-intensive group. The slightly higher death rate concerned the Data and Safety Monitoring Board (DSMB), who advised the research study lead, Elizabeth G. Nabel, M.D to stop the group receiving the higher intensity strategy for lowering blood glucose levels. This means that there is now only one group of participants, those receiving the less-intensive strategy to lower their blood glucose levels.

Of the participants, 257 in the intensive group died, while 203 in the standard treatment group died in the four years of treatment. The study researchers advise that the death rates of both groups (about 3 per 1,000) are lower than in other, similar studies.

The Data and Safety Monitoring Board (DSMB) are an independent advisory group of experts in diabetes, cardiovascular disease, epidemiology, patient care, biostatistics, medical ethics, and clinical trial design that has been monitoring ACCORD since it began.

“A thorough review of the data shows that the medical treatment strategy of intensively reducing blood sugar below current clinical guidelines causes harm in these especially high-risk patients with type 2 diabetes,” said Elizabeth G. Nabel, M.D., director, NHLBI. “Though we have stopped this part of the trial, we will continue to care for these participants, who now will receive the less-intensive standard treatment. In addition, we will continue to monitor the health of all participants, seek the underlying causes for this finding, and carry on with other important research within ACCORD.”



Resources
The National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health. For Safety, NHLBI Changes Intensive Blood Sugar Treatment Strategy in Clinical Trial of Diabetes and Cardiovascular Disease. Accessed 9 February 2008