Project 173038

Type 1 diabetes (T1D) is one of the most chronic diseases diagnosed in children, teenagers and young adults. It is a lifelong disease where the body produces little or no insulin. Children with diabetes use multiple daily insulin injections to control the disease along with following rigorous diets and restricted sugar consumption which disrupts their daily life and causes psychological, social and educational difficulties. Several studies suggest that specific exposures at critical periods in early life such as with Bacillus Calmette-Guérin (BCG) could affect how a child's immune system develops. The epidemiological evidence on the effect of BCG vaccination with regard to T1D is however sparse and inconsistent. A BCG vaccination campaign was held in Québec between 1949 and 1974 targeting newborns and school-age children. The vaccination records are kept in a registry at INRS-Institut Armand-Frappier. Our study will make use of this provincial registry to investigate the prospective effect of BCG vaccination on the development of T1D by performing record linkage of the BCG vaccination dataset with existing medical and socio-demographic databases from the Canadian province of Québec. This study will add to the current research of the potential health effects of immune stimulation in early age and will contribute to the knowledge on mechanisms and factors related to T1D.