CHICAGO, 10 june 2009-- Strict lowering of blood sugar may not have been the cause of excess deaths in a major study of patients with type 2 diabetes, U.S. researchers said on Tuesday.
The trial, known as ACCORD, studied the effects of intensive strategies to help diabetics get near-normal blood sugar levels, but was stopped in February 2008 because there were 20 percent more deaths among people who got intensive treatment compared with those who got standard treatment.
One theory about the deaths is that they may have been caused by hypoglycemia or seriously low blood glucose levels.
But an analysis of deaths in the study suggests that was not the case. In fact, among those who had an episode of severe hypoglycemia, the risk of dying was lower among patients in an arm of the study who had been treated more aggressively.
"At this point we do not believe severe hypoglycemia ... is responsible for the increased risk of death seen among intensive arm participants," Dr. Denise Bonds, one of the ACCORD investigators, told reporters at the American Diabetes Association meeting in New Orleans.
Results of the ACCORD trial challenged conventional thinking that helping diabetics reach blood sugar levels considered normal for healthy people would help them avoid some of the more deadly complications of their disease.
Now, researchers are looking to other factors, such as drug combinations or age, as potential reasons for the deaths. Many patients in the ACCORD study were treated with GlaxoSmithKline's rosiglitazone or Avandia as well as older drugs such as metformin.
"We're going in the direction of trying to identify groups of patients for whom different strategies and different goals for treatment will be most appropriate," said Dr. Matthew Riddle of Oregon Health & Science University, who helped lead the ACCORD study.
TIMING OF TREATMENT A FACTOR
In a second trial of intensive glucose control called VADT, which studied older veterans with type 2 diabetes, timing of treatment appeared to play a role in determining which patients benefited.
Results of that study, published in December 2008 in the New England Journal of Medicine, found intensive treatment overall did not help, and even raised heart risks.
A new analysis of that study found that people who were started on an intensive treatment strategy to lower their blood sugar within the first 15 years of diagnosis did have fewer heart risks, including death from heart disease.
But those who went on intensive treatment 16 to 20 years after diagnosis had no benefit, Dr. William Duckworth of VA Medical Center in Phoenix and the University of Arizona told the briefing.
And for people who had had diabetes for more than 21 years, the risk of a major heart event such as a heart attack more than doubled. "The simple take-home message I believe we have for this is treat early, and treat carefully," Duckworth said.
Researchers are continuing to analyze both studies, but Duckworth said individualized treatment appears to be the best approach for helping diabetics reduce their heart risks.
At least 170 million people worldwide are estimated to have diabetes, a number that is predicted to at least double by 2030. Most have type 2 diabetes.