The Type 1 Diabetes Prediction and Prevention (DIPP) Study in Finland is a population-based long-term clinical follow-up study established since 1994 in three university hospitals in Finland to understand the pathogenesis of type 1 diabetes (T1D), predict the disease, and find preventive treatment.

Briefly, cord blood samples are collected and HLA-DR-DQ genotypes are determined from newborn babies. Families with a newborn baby carrying a DR-DQ genotype associated with increased risk for T1D are invited to participate in regular follow-up at the age of 3, 6, 9, 12, 18 and 24 months, and thereafter once a year until the age of 15 years or until T1D is diagnosed. Clinical details including maternal diet during pregnancy and lactation and child's diet starting from the age of 3 months are recorded, blood samples are collected, and serum autoantibodies associated with development of T1D are measured. Children who develop beta-cell specific autoimmunity are followed more intensively with measurements of glucose metabolism parameters such as glycated haemoglobin A1c (HbA1c), oral glucose tolerance tests (OGTT) and intravenous glucose tolerance tests (IVGTT). In the DIPP Study more than 1000 children have developed multiple islet autoantibodies and more than 450 of these have progressed to clinical T1D. It has been estimated that 5% of children in the follow-up will develop T1D and 60% of future T1D cases will be reached by the current screening and follow-up strategy.

Inclusion Criteria:

• Newborn babies with HLA-conferred genetic susceptibility to type 1 diabetes born in three University Hospitals in Finland

Exclusion Criteria:

• Newborn babies without HLA-conferred genetic susceptibility to type 1 diabetes

Since November 1994 the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Study has screened 206,707 newborns for HLA-conferred genetic susceptibility for T1D (Figure 1., data as of March 2015). A total of 16,193 children have started clinical follow-up with regular study visits and systematic collection of longitudinal blood and stool samples. Altogether more than 1000 children have seroconverted to positivity for multiple islet autoantibodies (ICA included). A total of 461 children and adolescents have progressed to clinical T1D with DIPP follow-up from birth until diagnosis. Currently there are 7158 children between 3 months and 15 years of age taking part in the DIPP Study follow-up.