Study: Type 1s Positive for at Least One Additional Organ-specific Auto-antibody at Diagnosis
Today I want to discuss several unrelated tidbits about diabetes. The first cool snippet refers to a diabetes related application that can be downloaded via iTunes. It is referred to as "MealSnap." According to the iTunes Store description, the application will provide caloric information based on a picture taken by the iPhone. The picture is then matched to a database of approximately 500,000 food items and an almost instantaneous readout is transmitted to your iPhone depicting the number of calories. Apparently, you also may use the application to keep a log of your meals to help manage your dietary records. The application costs $2.99 and is in the "health and fitness" section. I did research on some of the user comments and most were favorable. However, one particular comment was both concerning and amusing. Apparently, the user took a photo of one Oreo cookie and obtained the calorie count. Then, he/she took a shot of two Oreo cookies and the calorie count was one less than the count for one cookie! Other users are entranced by its accuracy. Check it out!
Another tidbit is about a recent paper published in Diabetes Care online March 23, 2011, ahead of print: "One Third of Patients have Evidence for an Additional Autoimmune Disease at Type 1 Diagnosis." The authors, Triolo, Armstrong, McFann, Yu, Rewers, Klingensmith, Eisenbarth, and Barker, from the University of Colorado's Barbara Davis Center for Childhood Diabetes, provided an interesting analysis of the associated autoimmune diseases linked to chromosome 6 in the HLA area. The goal of the study was to "define the prevalence of nonislet, organ-specific autoantibodies at diagnosis of type 1 diabetes and to determine the prevalence of comorbid autoimmune diseases." Thus, 491 children who were diagnosed with type 1 diabetes (antibodies used to confirm diagnosis were: GAD antibody, islet cell antibody, insulin autoantibody, and zinc transporter 8 antibody) at the Barbara Davis Center for Childhood Diabetes were screened for thyroid disease (Hashimoto's or Graves) with thyroid peroxidase antibodies, celiac disease with tissue transglutaminase IgA antibodies, and Addison's disease with 21-hydroxylase autoantibodies.
What were the results? Of the 491 children diagnosed with type 1 diabetes:
- 408 were Non-Hispanic white (82.7%)
- 262 were males (53.4%)
- Mean age of type 1 diabetes diagnosis: 9.6 +/- 4.4 years
- Average HbA1c at diagnosis: 11.6 +/- 2.6%
- 160 children had at least 1 positive nonislet organ-specific antibody (32.6%)
- 122 were positive for thyroid peroxidase antibodies (24.8%)
- Of the 122 with positive thyroid peroxidase ab, 15 had autoimmune thyroid disease (12.3%)
- 5 were positive for 21 hydroxylase autoantibodies (1%)
- Of the 5 with positive 21 hydroxylase autoantibodies, 1 had Addison's disease
- 57 were positive for serum tissue transglutaminase antibodies (11.6%)
- Of the 57 with positive tissue transglutaminase antibodies, 14 had celiac disease (24.6%)
- Of the 14 diagnosed with celiac disease, 6 were diagnosed by endoscopy with biopsy and 8 were diagnosed by 2 consecutive positive serum tissue transglutaminase results and report of symptoms or gluten free diet, or both.
- Of the 161 children with at least one nonislet, organ-specific autoantibody, 30 (18.6%) were diagnosed with an additional autoimmune disease within an average of 46+/- 43 days of initial presentation of type 1 diabetes.
TAKE HOME MESSAGE: The study, although limited in terms of numbers of subjects, has demonstrated that approximately 33% of patients with type 1 diabetes are positive for at least one additional organ-specific autoantibody at diagnosis of type 1 diabetes and 19% had clinical disease. Additional studies will be needed to determine the length of time after diagnosis for the emergence of additional organ-specific autoantibodies and for the development of clinical disease after becoming antibody positive. In addition, this study underscores the importance of screening for these additional organ-specific antibodies at or near the time of diagnosis of type 1 diabetes.