People with type 1 diabetes may face a number of complications, including narrowed arteries. If patients gain better control of blood sugar levels, they may reduce their risk of these complications.
Transplanting pancreatic islet cells may improve narrowed arteries in patients with type 1 diabetes, according to recent research.
Islet cells are partly made of beta cells - the cells in the pancreas that produce insulin. In type 1 diabetes, these cells become damaged, which means the body does not get the insulin it needs to control levels of sugar in the blood.
The hardening and narrowing of the arteries - also called atherosclerosis - is a common complication of diabetes. Atherosclerosis occurs when fat, cholesterol and other substances build up to form plaque. The plaque buildup causes the arteries to narrow, making it harder for blood to flow through them. This puts patients at risk of clots that can lead to heart attack and stroke.
One marker of atherosclerosis is the thickness of the carotid arteries - the vessels that carry blood to the head, neck and brain.
Kristie K. Danielson, PhD, of the University of Illinois at Chicago, and colleagues found pancreatic islet transplantation reduced carotid artery thickness in patients with type 1 diabetes.
The decrease in carotid artery thickness was associated with a decrease in levels of HbA1c (blood sugar levels over time).
According to the study's authors, these findings suggest islet transplantation may improve diabetes-related atherosclerosis by improving blood sugar control in patients with type 1 diabetes.
Pancreatic islet transplantation is a procedure in which islets are taken from the pancreas of a deceased organ donor and then implanted in another person.
Once a diabetes patient has these new islets, the beta cells in the islets start to make insulin - a natural hormone that helps the body use sugar for energy.
From their study of 15 patients with type 1 diabetes, Dr. Danielson and colleagues found carotid intima-media thickness (a marker of atherosclerosis) decreased by about 0.058 mm 12 months after patients underwent islet transplantation.
The decrease continued from 12 to 50 months after islet transplantation.
Even though the thickness of the carotid artery is associated with atherosclerosis, thickening of the artery is not necessarily caused by atherosclerosis. However, once the carotid artery reaches a certain thickness, patients may almost certainly have atherosclerosis.
This study did not show that islet transplantation prevented atherosclerosis. Furthermore, the study did not show that islet transplantation directly caused the decrease in carotid artery thickness. Still, patients who underwent islet transplantation had improved HbA1c and better control of diabetes, which is known to reduce the risk of diabetes-related complications, including cardiovascular problems like atherosclerosis.
More research on larger groups of patients is needed to see if islet transplantation actually relieves atherosclerosis in patients with type 1 diabetes.
The study was published November 19 in Diabetes Care, a journal of the American Diabetes Association.