Younger Age at Onset of T1D:Several European studies
(60 - 63)
and one from
Colorado
(64)
have suggested a trend toward an earlier age at diagnosis of T1D. Based
on current m
odel-based rates of increase the EURODIAB study predicted a doubling
of new cases of T1D in European children younger than 5 years between 2005 and
2020
(8)
.
The reason for this rapid increase in the very young is unknown. It is
possible that this younger group has a higher proportion of HLA susceptibility genes,
but it is also possible that there is an increased disease penetrance in this age-group
due to harmful changes in environmental risk factors. In addition to estimating trends
in the incidence of T1D by age-group, SEARCH will also be able to explore temporal
trends in onset age and the possible interaction with changes in distribution of HLA
susceptibility genes, thus advancing the knowledge of T1D etiology.
