A JAMA THEME ISSUE
Edited by Catherine D. DeAngelis, MD, MPH, David S. Cooper, MD, and Phil B. Fontanarosa, MD, MBA
In the Detection of Ischemia in Asymptomatic Diabetics study, the investigators assessed whether routine screening for coronary artery disease with adenosine-stress radionuclide myocardial perfusion imaging (MPI) identifies patients with type 2 diabetes who are at high risk of cardiac events and whether such identification influences patients' cardiac outcomes. Over a mean (SD) follow-up of 4.8 (0.9) years, Young and colleagues found that cardiac event rates were low and not significantly reduced by MPI screening of asymptomatic patients.
Both hyperglycemia and hypoglycemia increase the risk of mortality among patients with acute myocardial infarction (MI). Whether episodic hypoglycemia from glucose-lowering therapy is harmful to patients with acute MI remains unresolved. Kosiborod and colleagues analyzed data from a retrospective cohort of patients with acute MI who were hyperglycemic when admitted to the hospital and found that the mortality risk associated with hypoglycemia was limited to patients who developed hypoglycemia spontaneously. Insulin-related hypoglycemia was not associated with a higher mortality risk.
An association between severe hypoglycemia and impaired cognitive function has been reported among children and young adults with type 1 diabetes. Whether hypoglycemia severe enough to require hospitalization is associated with dementia risk among older patients with type 2 diabetes is not known. In an analysis of longitudinal data from patients with type 2 diabetes and a mean age of 65 years, Whitmer and colleagues found that a history of 1 or more severe hypoglycemic episodes was associated with an increased risk of dementia.
Previously, Couri and colleagues reported that 15 patients with newly diagnosed type 1 diabetes who underwent autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT) achieved insulin independence. In this issue, the authors report results from an expanded cohort of 23 patients who underwent HSCT. During a mean 29.8 month follow-up (range, 7-58 months), the authors found that 20 patients became insulin-free, 12 of whom remained insulin independent with good glycemic control for a mean of 31 months. To investigate whether insulin independence is due to preservation of beta-cell mass rather than dietary and exercise changes associated with intensive medical care following transplantation, the authors analyzed C-peptide levels—an indirect measure of viable beta-cell function—and found that C-peptide levels increased significantly following HSCT transplantation.
Human pancreatic islets are a critical resource in investigations of the biology and treatment of diabetes. Kaddis and colleagues reviewed data collected by the national Islet Resource Consortium and report their findings relating to the supply and demand for pancreatic islets, the funding and scientific impact of islet studies, and the operation of an islet distribution program. The authors discuss the clinical utility of human islets and alternatives to human islet preparations for research applications.
“Does failure to check an HBA1c level mean I am a worse physician?” From “The Tyranny of the Measuring Cup.”
Scientists hope islet cell transplantation or an artificial pancreas may one day improve treatment of diabetes.
Can diabetes be cured?
Bariatric surgery and diabetes
Public health response to diabetes
Glucose control in type 2 diabetes
Progress in diabetes research: what's next?
How would you manage a 51-year-old woman with an acute onset of facial pressure, rhinorrhea, and tooth pain? Go to www.jama.com to read the case and submit your response, which may be selected for online publication. Submission deadline is April 29.
For your patients: Information about diabetes.
This Week in JAMA . JAMA. 2009;301(15):1507. doi:10.1001/jama.281.16.1465