Type 1 Diabetes Research Updates
The November issue of Diabetes Care has type 1 diabetes research updates ranging from behavioral research to islet cell transplants. I would like to take this opportunity to summarize several of the different studies as presented in this latest issue to provide some of the multidirectional approaches of research in type 1 diabetes. (Diabetes Care, November 2011, 34 (11).)
First, some good epidemiologic news for those who are diagnosed with type 1 diabetes!
- In a study by Larsson et. al, "Reduced Prevalence of Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes in Young Children Participating in Longitudinal Follow-Up" (2347-2352), the objective was to determine whether knowledge of genetic risk and close follow-up for the development of islet autoantibodies through participation in The Environmental Determinants of Diabetes in the Young (TEDDY) study results in lower prevalence of DKA at diabetes onset in children less than 2 years of age and less than 5 years of age compared with population based studies. The conclusion was that, yes, indeed (and statistically significant), participation in the TEDDY study was associated with reduced risk of DKA at diagnosis in T1DM in young children.
Why is this important? DKA at diagnosis has been demonstrated, through the research of Glaser and others, to effect cognition and memory longitudinally.
2. Additional good news has been reported for microvascular complications in
Adolescents with type 1 diabetes. In her paper, "Continued Reduction in the prevalence of Retinopathy in Adolescents with Type 1 Diabetes" (2368-2373), Dr Downie examined trends in microvascular complications in adolescents with diabetes between 1990-2009 in Sydney, Australia. Retinopathy declined as did microalbuminura (statistically significant). Multiple daily injections and insulin pump therapy use increased, median Hb A1c decreased, and severe hypoglycemia was unchanged. Retinopathy was associated with diabetes duration, hb A1c, systolic blood pressure, socioeconomic disadvantage, and 1-2 injections per day.
Why is this important? The decease in retinopathy lends further support for the present guidelines in recommending the present glycemic targets in children and adolescents, as well as the use of multiple daily injections and insulin pump therapy.
- And for those waiting for the artificial pancreas, Berenstal, Tamborlane et al. published "Sensor-Augmented Pump Therapy for A1c Reduction (Star 3) Study: Results from the 6-month Continuation Phase" (2403-2405). The conclusions were as follows: switching from optimized MDI to Sensor Augmented insulin pump therapy allowed for rapid and safe A1c reductions and persist for at least 18 months.
Why is this important? These data provide more supporting evidence for the marriage of the insulin pump to the continuous glucose sensor and assists with motivating the FDA to eventually approve the technology.
- What about islet cell transplants? In the paper "Long-Term Metabolic and Immunological Follow-up of Nonimmunosuppressed Patients with Type 1 Diabetes Treated With Microencapsulated Islet Allographs" (2406-2409), Basta et.al., assessed long-term metabolic and immunologic follow-up of microencapsulated human islet allographs (transplanted intraperitoneally) in 4 nonimmunosuppressed patients with T1DM. All patients produced C-peptide, both in basal and after stimulation up to 3 years of post transplant follow-up. Daily mean blood glucose, as well as HbA1c levels significantly improved after transplant, with insulin dosages decreasing in all patients and being discontinued temporarily in only ¼ transplanted patients. GAD 65 antibodies all tested NEGATIVE at 3 years after transplant. Of most importance, the grafts did NOT elicit any immune reaction even with multiple transplants. The authors conclude that the encapsulation resulted in "bioinvisibility" of the grafted islets.
Why is this important? NO immunosuppression required with microencapsulated islet cell allographs and production of c-peptide indicating insulin formation! However, this has been achieved in only four patients and larger trials will need to be conducted.
- Finally, we have a behavioral research trial that looks at "Associations between Media Consumption Habits, Physical Activity, Socioeconomic Status, and Glycemic Control in Children, Adolescents and Young Adults with T1DM" (2356-2359). Dr. Galler et.al proceeded to evaluate 296 children, adolescents, and young adults with type 1 diabetes and obtained statistical information and hb A1c levels. They analyzed risk factors by multiple regression analysis.
What did they find? Diabetes duration, socioeconomic status, and daily media consumption time, but not physical activity, were significant risk factors for glycemic control in youth with T1DM. Of note, adolescents who reported watching more television had increased unhealthy food consumption as well as more insulin omissions.
Why is this important? Physical activity is a key factor in glycemic management. Increased time playing video games, watching TV, etc., translates to less time for physical activity. (Active participation games such as Wii are the notable exceptions.)