Incident dysglycemia and progression to type 1 diabetes among participants in the Diabetes Prevention Trial-Type 1.
OBJECTIVE
We studied the incidence of dysglycemia and its prediction of the development of type 1 diabetes in islet cell autoantibody (ICA)-positive individuals. In addition, we assessed whether dysglycemia was sustained.


METHODS
Participants (n = 515) in the Diabetes Prevention Trial-Type 1 (DPT-1) with normal glucose tolerance who underwent periodic oral glucose tolerance tests (OGTTs) were followed for incident dysglycemia (impaired fasting glucose, impaired glucose tolerance, and/or high glucose levels at intermediate time points of OGTTs). Incident dysglycemia at the 6-month visit was assessed for type 1 diabetes prediction.


RESULTS
Of 515 participants with a normal baseline OGTT, 310 (60%) had at least one episode of dysglycemia over a maximum follow-up of 7 years. Dysglycemia at the 6-month visit was highly predictive of the development of type 1 diabetes, both in those aged <13 years (P < 0.001) and those aged > or =13 years (P < 0.01). Those aged <13 years with dysglycemia at the 6-month visit had a high cumulative incidence (94% estimate by 5 years). Among those who developed type 1 diabetes after a dysglycemic OGTT and who had at least two OGTTs after the dysglycemic OGTT, 33 of 64 (52%) reverted back to a normal OGTT. However, 26 (79%) of the 33 then had another dysglycemic OGTT before diagnosis.


CONCLUSIONS
ICA-positive individuals with normal glucose tolerance had a high incidence of dysglycemia. Incident dysglycemia in those who are ICA positive is strongly predictive of type 1 diabetes. Children with incident dysglycemia have an especially high risk. Fluctuations in and out of the dysglycemic state are not uncommon before the onset of type 1 diabetes.
Sosenko
Jay M
JM
Division of Endocrinology, University of Miami, Miami, Florida, USA. jsosenko@med.miami.edu
Palmer
Jerry P
JP
Rafkin-Mervis
Lisa
L
Krischer
Jeffrey P
JP
Cuthbertson
David
D
Mahon
Jeffery
J
Greenbaum
Carla J
CJ
Cowie
Catherine C
CC
Skyler
Jay S
JS
D000293:Adolescent; D001786:Blood Glucose; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control*; D005260:Female; D018149:Glucose Intolerance / Q000097:blood; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models
D001786:Blood Glucose