OBJECTIVE—To assess whether the detection of enterovirus
RNA in blood predicts the development of clinical type 1 diabetes
in a prospective birth cohort study. Further, to study the role of
enteroviruses in both the initiation of the process and the
progression to type 1 diabetes.
RESEARCH DESIGN AND METHODS—This was a nested
case-control study where all case children (N 38) have
progressed to clinical type 1 diabetes. Nondiabetic control children
(N 140) were pairwise matched for sex, date of birth,
hospital district, and HLA-DQ–conferred genetic susceptibility to
type 1 diabetes. Serum samples, drawn at 3- to 12-month intervals,
were screened for enterovirus RNA using RT-PCR.
RESULTS—Enterovirus RNA–positive samples were more frequent
among the case subjects than among the control subjects.
A total of 5.1% of the samples (17 of 333) in the case group were
enterovirus RNA–positive compared with 1.9% of the samples (19
of 993) in the control group (P 0.01). The strongest risk for
type 1 diabetes was related to enterovirus RNA positivity during
the 6-month period preceding the first autoantibody-positive
sample (odds ratio 7.7 [95% CI 1.9 –31.5]). This risk effect was
stronger in boys than in girls.
CONCLUSIONS—The present study supports the hypothesis
that enteroviruses play a role in the pathogenesis of type 1
diabetes, especially in the initiation of the -cell damaging
process. The enterovirus-associated risk for type 1 diabetes may
be stronger in boys than in girls.