Washington, April 1 : A new study which compared two types of drugs to treat type 2 diabetes, has found that pioglitazone is better than glimepiride at slowing the rate of progression of atherosclerosis, a process in which plaque build-up in the coronary arteries.
Atherosclerosis in patients with diabetes is particularly aggressive, characterized by higher cardiovascular event rates and determining the optimal treatment for coronary artery disease for patients with diabetes has important public health implications, according to the researchers at Cleveland Clinic.
For the study, Steven E. Nissen, M.D., of the Cleveland Clinic, and colleagues conducted the PERISCOPE trial to directly compare the effectiveness of two alternative approaches for treating hyperglycemia, an insulin-providing strategy (glimepiride) vs. an insulin-sensitizing strategy (pioglitazone), in reducing progression of atherosclerosis in 543 patients with type 2 diabetes and coronary disease.
The patients underwent coronary intravascular ultrasonography to measure progression of atherosclerosis and were randomised to receive glimepiride or pioglitazone for 18 months.
The researchers measured atherosclerosis progression by the change in percent atheroma volume (PAV; a measurement of plaque build-up in an artery) with repeat intravascular ultrasonography examination in 360 patients at study completion.
It was found that the primary efficacy measure, change in PAV, increased 0.73 percent in the glimepiride group and decreased 0.16 percent in the pioglitazone group.
An alternative analysis imputing values for patients who did not have follow-up ultrasound procedures and based on baseline characteristics showed an increase in PAV of 0.64 percent for glimepiride and a decrease of 0.06 percent for pioglitazone.
The researchers found that a secondary efficacy measure, change in maximum atheroma thickness increased in the glimepiride group and decreased in the pioglitazone group.
"The observation of a significant benefit for pioglitazone treatment represents, to our knowledge, the first demonstration of the ability of any hypoglycemic agent to slow the progression of coronary atherosclerosis in patients with diabetes.
"These finding may have important implications for defining the optimal strategy for management of patients with type 2 diabetes and coronary atherosclerosis," the researchers said.
The study is published in the April 2 issue of JAMA.