Refereed journal article or data article (A1)
HbA(1c) Predicts Time to Diagnosis of Type 1 Diabetes in Children at Risk
List of Authors: Helminen O, Aspholm S, Pokka T, Hautakangas MR, Haatanen N, Lempainen J, Ilonen J, Simell O, Knip M, Veijola R
Publisher: AMER DIABETES ASSOC
Publication year: 2015
Journal: Diabetes
Journal name in source: DIABETES
Journal acronym: DIABETES
Volume number: 64
Issue number: 5
Start page: 1719
End page: 1727
Number of pages: 9
ISSN: 0012-1797
eISSN: 1939-327X
DOI: http://dx.doi.org/10.2337/db14-0497
Prediction of type 1 diabetes is based on the detection of multiple islet autoantibodies in subjects who are at increased genetic risk. Prediction of the timing of diagnosis is challenging, however. We assessed the utility of HbA(1c) levels in predicting the clinical disease in genetically predisposed children with multiple autoantibodies. Cord blood samples from 168,055 newborn infants were screened for class II HLA genotypes in Finland, and 14,876 children with increased genetic risk for type 1 diabetes were invited to participate in regular follow-ups, including screening for diabetes-associated autoantibodies. When two or more autoantibodies were detected, HbA(1c) levels were analyzed at each visit. During follow-up, multiple (two or more) autoantibodies developed in 466 children; type 1 diabetes was diagnosed in 201 of these children (43%, progressors), while 265 children remained disease free (nonprogressors) by December 2011. A 10% increase in HbA(1c) levels in samples obtained 3-12 months apart predicted the diagnosis of clinical disease (hazard ratio [HR] 5.7 [95% CI 4.1-7.9]) after a median time of 1.1 years (interquartile range [IQR] 0.6-3.1 years) from the observed rise of HbA(1c). If the HbA(1c) level was 5.9% (41 mmol/mol) in two consecutive samples, the median time to diagnosis was 0.9 years (IQR 0.3-1.5, HR 11.9 [95% CI 8.8-16.0]). In conclusion, HbA(1c) is a useful biochemical marker when predicting the time to diagnosis of type 1 diabetes in children with multiple autoantibodies.