Diabetes Care, Vol 16, Issue 1 45-50, Copyright © 1993 by American Diabetes Association
Can islet cell antibodies predict IDDM in the general population?
PJ Bingley, E Bonifacio, M Shattock, HA Gillmor, PA Sawtell, DB Dunger, RD Scott, GF Bottazzo and EA Gale
Department of Diabetes and Metabolism, St. Bartholomew's Hospital, London, United Kingdom.
OBJECTIVE--To evaluate the likely prognostic significance of ICAs in
children with no family history of IDDM. RESEARCH DESIGN AND METHODS--We
examined the prevalence of ICAs in 2925 English schoolchildren aged 9-13 yr
and in 274 age-matched siblings of children with diabetes from the same
region, and we compared the estimated risk of progression to diabetes
within 10 yr in the two groups. RESULTS--ICAs were present at levels >
or = 4 JDF U in 2.8% of schoolchildren and 6.6% of siblings and at > or
= 20 JDF U in 0.8% of schoolchildren and 2.2% of siblings. Although ICAs
are only 2-3 times more prevalent in siblings than schoolchildren, the
estimated cumulative risk that siblings will progress to diabetes by age 21
is 13 times greater (2.8 vs. 0.21%). CONCLUSIONS--ICAs are unexpectedly
prevalent in English schoolchildren, but only a small minority, with this
evidence of immune activation directed against islet cells, will progress
to diabetes. Although ICAs alone have limited predictive value in the
general population, combining two or more predictive tests in series could
achieve a level of prediction equivalent to that now obtained in
first-degree relatives.