A New Definition of the Partial Remission Phase in Children and Adolescents with Type 1 Diabetes. Results from The Hvidoere Study Group
Abstract Number: 1784-P
Authors: SVEN PÖRKSEN, ANNE KAAS KASTANIEGAARD, PETER SWIFT, LARS HANSEN, HENRIK B. MORTENSEN, PHILIP HOUGAARD, Glostrup, Denmark, Leicester Royal Infirmery, United Kingdom, Odense, Denmark
Institutions: Glostrup, Denmark; Leicester Royal Infirmery, United Kingdom; Odense, Denmark
Results: The definition of the remission period in children and adolescents varies among studies in the literature making a uniform clinical and scientific interpretation of this period in type 1 diabetes pathogenesis difficult. The objective of the current longitudinal investigation is to find a simple definition, which reflects the underlying disease state (residual betacell function) rather than the insulin treatment and is based on routinely available data. The study design was multicentre longitudinal investigation in 18 paediatric departments representing 15 countries in Europe and Japan. 275 children and adolescents less than 16 yrs with newly diagnosed type 1 diabetes were enrolled between August 1999 and December 2000. HbA1c and stimulated C-peptide were analysed centrally. After 1, 6 and 12 months of diabetes a mixed meal tolerance test (MMTT) (Sustacal/Boost) was utilized to stimulate endogenous C-peptide release.
By multiple regression analysis with C-peptide as dependent variable and sex, age, HbA1c and daily insulin dose (U/kg) as independent variables, a negative association between stimulated C-peptide and HbA1c (-0.21, regression coefficient, P<0.001) and insulin dose (-0.87, regression coefficient, p<0.001) was shown. From the regression coefficients an insulin dose-adjusted HbA1C was suggested as: actual HbA1c (%)+ (4 x insulin dose (U/Kg/24h). A calculated insulin dose adjusted HbA1c below 9 corresponded to a predicted maximal C-peptide level above 300pmol/l and was used to define partial remission. The agreement between definitions of remission, HbA1c <7.5%, dose adjusted HbA1c <9% , insulin dose <0.5 U/kg/d was compared to stimulated C-peptide >300 pmol/l, which is the level corresponding to the C-peptide responders in the DCCT trial (200-500 pmol/l). The dose adjusted HbA1c model had a significantly higher agreement (p <0.001) with the C-peptide expression than the raw HbA1c. The new definition of remission is convenient and easy to use, because it does not require the Boost challenge test, and it is comparable with a stimulated C-peptide response of 300 pmol/l.