Highlights From the American Diabetes Association’s Scientific Sessions
By Janice Holm, MPH, RD, CHES
More than 12,000 healthcare professionals gathered in New Orleans from June 5 to 9 for the American Diabetes Association’s 69th Annual Scientific Sessions. These sessions attract diabetes professionals from around the world, as cutting-edge research, treatments, and education strategies are revealed and discussed each year. The following are highlights from this year’s meeting.
RECORD Clinical Trial Results
Rosiglitazone is an insulin sensitizer used for lowering glucose either alone or in conjunction with metformin and/or a sulfonylurea in people with type 2 diabetes. The RECORD (Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycaemia in Diabetes) trial was a 5½-year study conducted in 338 centers in 23 countries throughout Europe, Australia, and New Zealand. This trial examined the long-term impact of rosiglitazone on cardiovascular outcomes and blood glucose control compared with metformin or sulfonylurea drugs.
Philip D. Home, DM, DPhil, who presented the results, said, “Provided known contraindications and cautions are observed, physicians should be comfortable prescribing rosiglitazone for their diabetes patients.” This statement comes after the 2008 meta-analysis by Steven Nissen, MD, was published warning of increased cardiac risks in patients using rosiglitazone. Nissen’s meta-analysis spurred much controversy and incidentally changed the course of diabetes treatment, as many physicians and entire medical facilities chose to stop prescribing rosiglitazone to patients. RECORD is the first trial since the meta-analysis to indicate overall cardiovascular safety with rosiglitazone.
In fact, rosiglitazone was shown to be superior in controlling blood glucose levels compared with metformin and sulfonylurea therapies. After five years, rosiglitazone patients had hemoglobin A1c levels 0.29% lower than those on sulfonylureas and 0.26% lower than those on metformin. Rosiglitazone is not recommended for use in patients with congestive heart failure, nor is it recommended in very elderly women due to the increased risk of bone fracture should they fall.
BARI 2D Clinical Trial Results
BARI 2D (Bypass Angioplasty Revascularization Investigation in Type 2 Diabetes), a multicenter trial led by the University of Pittsburgh Graduate School of Public Health, studied whether angioplasty or bypass surgery in patients with type 2 diabetes is better than initial treatment with pharmacotherapy alone. Investigators also compared two approaches to controlling blood sugar: insulin-sensitizing vs. insulin-providing medications. The results show that prompt bypass surgery or angioplasty does not lower mortality risk compared with drug therapy in type 2 diabetes patients with stable heart disease.
VADT (VA Diabetes Trial) and ACCORD Trial Updates
Researchers halted the intensive arm (target hemoglobin A1c less than 6%) of the ACCORD (Action to Control Cardiovascular Risk in Diabetes) study last year after discovering that the group was experiencing a higher death rate than the group receiving conventional treatment. This spurred much discussion at last year’s scientific sessions, as researchers speculated about why the intensive group may have experienced an increased mortality rate.
New research revealed at this year’s sessions shows that hypoglycemic events do not explain the excess deaths seen in the intensive control group. In fact, the researchers found that the risk of death actually increased for every hemoglobin A1c percentage point over 6%. Researchers are conducting further analyses to identify the potential cause of the increased mortality.
The VADT did not report excessive deaths from intensive control last year; however, the trial also did not find any statistically significant benefits of intensive glucose control. Upon further analysis, which was presented at the sessions this June, William C. Duckworth, MD, of the VA Medical Center in Phoenix reported that individualization is the key. Duckworth suggested that one important consideration for determining glycemic targets for an individual patient is his or her duration of diabetes. A reduction in cardiovascular events and mortality rates was seen with intensive glucose control if initiated between four and 15 years after diagnosis. Beyond 15 years, researchers began to see a U-shaped curve. Cardiovascular risk and death were somewhat elevated in those who started intensive therapy 15 years after diagnosis, and they were doubled among those starting after 20 years’ duration. Duckworth recommended considering the duration of diabetes in treatment decisions.
Using Hemoglobin A1c to Diagnose Diabetes
An international expert committee assembled by the American Diabetes Association, International Diabetes Federation, and European Association for the Study of Diabetes announced its recommendation for the use of the A1c assay to diagnose diabetes. The three diabetes organizations have not yet officially endorsed the recommendation.
Currently, two tests are used to diagnose diabetes: the fasting plasma glucose and, less commonly, the oral glucose tolerance test. The committee’s report recommends diabetes instead be diagnosed when A1c is greater than 6.5% and that those with A1c levels below the threshold for diabetes but over 6% receive preventive interventions. The committee examined the relationship between long-term glycemia and complications and concluded that the A1c test may serve as a better marker of diabetes and should be used as a diagnostic test. The committee’s report is published in a recent issue of Diabetes Care.
— Janice Holm, MPH, RD, CHES, is an outpatient dietitian at the VA Healthcare System in Long Beach, Calif., and an adjunct faculty member at California State University, Fullerton and Fullerton College.