Around-the-clock monitors benefit type-1 diabetes patients
Night-and-day glucose tracking helps type-1 diabetes patients stay healthy and safe, according to a clinical trial of a new class of glucose meter - a pager-sized device that continuously measures sugar levels through a small, fine wire worn under the skin.
The meter can be programmed to warn patients if their levels of glucose, the body's predominant sugar, rise too high or drop too low. It could help them fend off treacherous drops in blood glucose levels and decrease their risk of developing long-term complications, such as blindness and kidney failure.
The study, which tracked 322 type-1 diabetes patients at 10 medical centers, including 40 patients at the medical school and Lucile Packard Children's Hospital, is the first randomized clinical trial to show that this monitoring enables people with diabetes to take better care of themselves.'This technology allows patients to see exactly what's going on with their diabetes all the time,' said Bruce Buckingham, MD, professor of pediatric endocrinology at the medical school and leader of the Stanford/Packard portion of the study.
Traditional, finger-prick blood glucose meters give a few snapshots per day of a patient's diabetes management. In contrast, the new meters produce a 24-hour glucose 'movie,' recording glucose trends around meals, during exercise and throughout sleep.
The study, published online Sept. 8 by the New England Journal of Medicine, tracked child, adolescent and adult type-1 diabetes patients for six months. The subjects started with average sugar levels above or at the American Diabetes Association target for diabetes management. At checkups, doctors monitored the patients' blood levels of glycated hemoglobin, an indicator of long-term glucose control. (Low levels have been associated with a reduced risk of long-term complications.) The study's control subjects used only finger-prick blood glucose meters, in which a small drop of blood from the finger is applied to the meter to track glucose levels.
Adult patients age 25 and older were best at using the new meters and experienced the greatest improvement in glucose control. After six months, 83 percent of the adult subjects were wearing their monitors at least six days per week. Seventeen percent of these patients had glycated hemoglobin levels that met ADA treatment recommendations, as compared with 4 percent of the control group. Although their sugar levels were lower, patients performing continuous glucose monitoring did not have any greater risk than the control group of the extreme-low glucose levels that could cause seizures or loss of consciousness.
Children and adolescents were less consistent about using the new meters than adults, with 50 percent of children and 30 percent of adolescents wearing them six days per week after six months.
'One of the major things that determined patients' outcomes was whether they wore the continuous meters and used the data,' said Buckingham, who is also a pediatric endocrinologist at Packard Children's. On average, the children and adolescents using the sensor had similar glycated hemoglobin levels to those using only finger-prick sugar testing. However, individual pediatric and adolescent patients who wore the continuous meters consistently had better-than-average sugar control, he said. The study results may indicate that younger type-1 diabetes patients need to be offered the new sensors on a trial basis to test whether they wear them at least six days a week and use the additional data to manage their disease, he added.
Jennifer Block, RN, certified diabetes educator at Packard Children's, helped run the study at Stanford, along with Darrell Wilson, MD, professor of pediatrics and Packard's chief of pediatric endocrinology, and Packard nurse-practioner Kari Benassi, RN.
The Juvenile Diabetes Research Foundation funded the trial. Buckingham has received funding from Abbott Diabetes Care Inc., Medtronic MiniMed Inc. and Novo Nordisk Inc, and served on a medical advisory board for Lifescan, Inc. Wilson has received equipment and software from Abbott and Medtronic MiniMed, and research support from Medtronic MiniMed. Abbott makes continuous glucose monitors and finger-prick blood glucose meters; Lifescan makes finger-prick blood glucose meters; Medtronic MiniMed makes continuous glucose monitors, and Novo Nordisk makes insulin and insulin-delivery devices.
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