It used to be very simple, 25-years ago when diabetes was either classified as adult (type 2-non-insulin dependant) or juvenile (type1-insulin dependant). Generally, the kids got insulin and the adults were initially treated with lifestyle modification and several types of oral medications. As the disease progressed in people with type 2 diabetes, insulin was often initiated. The classification of diabetes is now very detailed with multiple types (see previous blogs). As such, medications once only used in adults with type 2 diabetes have now migrated to pediatric diabetes for use in those children and adolescents with type 2 and now for many with type 1.
Examples of oral medications include the use of sulfonylureas (glyburide), which was used in type 2 diabetes and is now the medication of choice in Permanent Neonatal Diabetes. Metformin (Glucophage), primarily used as an insulin sensitizer in type 2 diabetes, is now often utilized in the same fashion for type 1 diabetes to decrease insulin resistance. Use of Metformin is appropriate for adolescents with Polycystic Ovary Syndrome who either have type 1 or type 2 diabetes to decrease insulin resistance and improve ovulation. As a result of the decreased insulin resistance, insulin dosages often decrease with associated weight loss. Now, as a result of a new study, it appears that a GLP-1 receptor agonist, Victoza, an injection used primarily in type 2 diabetes, improves blood glucose further in those with well-controlled type 1 diabetes.
What is a GLP-1 receptor agonist? These medications belong to a relatively new class that mimics the natural GLP-1 peptide, which is normally released into the intestine after eating. The function of the GLP-1 peptide is to increase insulin secretion from the pancreatic beta cells when the blood sugar spikes and to slow glucose absorption from the digestive system. Glucagon, a counter-regulatory hormone, also is decreased. (Recall that Glucagon breaks down stored glycogen in the liver to increase blood sugar during a hypoglycemic episode.) All of these functions serve to lower blood sugar.
The findings presented by Dr. Paresh Dandona during the June 2011 Endocrine Society meetings were significant in view of the fact that these medications have not been implemented in people with type 1 diabetes due to the fact that no insulin is available secondary to pancreatic destruction of islet cells. In this small pilot study, 14 adults with well controlled diabetes on the insulin pump were given Victoza once daily for 1 week vs. 24 weeks. Continuous glucose monitoring prior to the study revealed very tight control of blood sugars; however, unpredictable fluctuations did occur. After Victoza was added to insulin pump therapy, CGMS documented decreases in blood sugar fluctuation and after 7 days, the average dosage of bolus insulin decreased by 30 percent, along with a decreased total daily dose of 32 percent. Patients who received Victoza treatment in the 24-week arm of the study had an additional decrease in insulin dosages and lost an average of 10 pounds secondary to decreased appetite and caloric reduction. The hb A1c level decreased from 6.5 to 6.1 percent (not statistically significant based on the small number of study participants).
Dr. Dandona concluded that "people with well-controlled type 1 diabetes had better sugar control, used less insulin, and lost an average of 10 pounds in 6 months when taking Victoza. Those who continued treatment for a full year continued these improvements especially decreased fluctuations of blood sugar." (Sources: WebMD, Endocrine Society News)
There are significant caveats to the benefits of this small study:
- The medication is given by injection (already adding to the insulin given by injection or insulin pump)
- Abdominal pain, nausea and vomiting (may resolve after several weeks)
- Study included only 14 subjects, and many more will need to be included to obtain statistical significance. Thus, a larger study will need to be performed.
- The medication is "off-label" for type 1 diabetes (but we use many medications in pediatrics that are "off label")
- The study was conducted in adults only
I look forward to further research in this area and will keep you posted.
Published On: June 14, 2011