New England Journal of Medicine Volume 350:1398-1404 April 1,
2004 Number 14
Childhood Vaccination and Type 1 Diabetes
Anders Hviid, M.Sc., Michael Stellfeld, M.D., Jan Wohlfahrt,
M.Sc., and Mads Melbye, M.D., Ph.D.
Background A link between childhood vaccinations and
the development of type 1 diabetes has been proposed.
Methods We evaluated a cohort comprising all children
born in Denmark from January 1, 1990, through December 31, 2000,
for whom detailed information on vaccinations and type 1 diabetes
was available. Using Poisson regression models, we estimated
rate ratios according to vaccination status, including the trend
associated with the number of doses, among all children and
in a subgroup of children who had siblings with type 1 diabetes.
Given recent claims of clustering of cases of diabetes two to
four years after vaccination, we also estimated rate ratios
during the period after vaccination.
Results Type 1 diabetes was diagnosed in 681 children
during 4,720,517 person-years of follow-up. The rate ratio for
type 1 diabetes among children who received at least one dose
of vaccine, as compared with unvaccinated children, was 0.91
(95 percent confidence interval, 0.74 to 1.12) for Haemophilus
influenzae type b vaccine; 1.02 (95 percent confidence interval,
0.75 to 1.37) for diphtheria, tetanus, and inactivated poliovirus
vaccine; 0.96 (95 percent confidence interval, 0.71 to 1.30)
for diphtheria, tetanus, acellular pertussis, and inactivated
poliovirus vaccine; 1.06 (95 percent confidence interval, 0.80
to 1.40) for whole-cell pertussis vaccine; 1.14 (95 percent
confidence interval, 0.90 to 1.45) for measles, mumps, and rubella
vaccine; and 1.08 (95 percent confidence interval, 0.74 to 1.57)
for oral poliovirus vaccine. The development of type 1 diabetes
in genetically predisposed children (defined as those who had
siblings with type 1 diabetes) was not significantly associated
with vaccination. Furthermore, there was no evidence of any
clustering of cases two to four years after vaccination with
Conclusions These results do not support a causal relation
between childhood vaccination and type 1 diabetes.
From the Danish Epidemiology Science Centre, Department of Epidemiology
Research (A.H., J.W., M.M.), and the Medical Department (M.S.),
Statens Serum Institut, Copenhagen, Denmark.
Address reprint requests to Mr. Hviid at the Danish Epidemiology
Science Centre, Department of Epidemiology Research, Statens
Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark,
or at firstname.lastname@example.org.