Celiac disease shares many genetic factors with T1Diabetes
NIDDK study continues to look at
possible factors that lead to the development of the diseases in children.
New results and information surrounding
potential "triggers" of the autoimmune process leading to type 1
diabetes (T1D) and how they interact with genetic factors in children at-risk
for developing the disease were highlighted in the "Update from the TEDDY
Study" symposium today at the American Diabetes Association's® (ADA's)
80th Virtual Scientific Sessions. Similar evidence for celiac disease is also
being accumulated through the large international study program. The data The
Environmental Determinants of Diabetes in the Young (TEDDY) study has collected
prospectively since 2004 will be utilized in new clinical trials to prevent
these autoimmune diseases that jointly affect more than 3% of the general
population.
TEDDY is an international multi-center trial researching the potential causes T1D in children. The study is funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). T1D occurs when the beta cells of the pancreas that normally make insulin are destroyed by the body's own immune system. When the beta cells are destroyed, the body cannot make insulin and maintain normal blood sugar levels.
Children who have T1D have certain types of genes, but not all children who have those genes develop diabetes. Something from the environment "triggers" the immune destruction of the beta cells. TEDDY is aiming to discover viruses and nutritional factors that interact with genes to "trigger" immune destruction of the beta cells, marked by the appearance of islet autoantibodies. The study enrolls infants identified as "at-risk" for developing T1D and follows them for 15 years to look for the appearance of various beta-cell autoantibodies and diabetes. TEDDY has also studied biomarkers that can predict faster or slower progression to diabetes after the autoimmune destruction has begun.
"An interesting finding from TEDDY has been how early the autoimmune destruction of insulin-producing cells begins – often in the initial two years of life," said study TEDDY co-chair Marian Rewers, MD, PhD, a professor of pediatrics and medicine and executive director of the Barbara Davis Center for Diabetes at the University of Colorado School of Medicine. "There appear to be two subtypes of T1D that differ by genetic factors and immune phenotypes. Metabolomic biomarkers may offer clues to the subtypes and whether a child develops T1D. Interestingly, HbA1c has very different predictive characteristics for progression to clinical diabetes in children with islet autoantibodies, compared to adults with risk factors for type 1 diabetes."
Additional key updates from the study group
include:
Persistent presence of enterovirus B species
in a child's stool predicts development of islet autoimmunity, especially the
earlier subtype characterized by the presence of autoantibodies to insulin.
There are
also subtle differences in the composition and function of gut microbiome in
children who develop islet autoantibodies, compared to controls. Early use of
probiotics may decrease the risk, while use of antibiotics was not related to
islet or celiac autoimmunity.
TEDDY has
also found potentially beneficial effects of vitamin D, vitamin C, or a diet
rich in polyunsaturated fatty acids, though these observations need to be
confirmed in randomized clinical trials.
Celiac
disease, another autoimmune condition, shares many genetic factors with T1D,
noted Dr. Rewers. TEDDY investigators follow study participants for both T1D
and celiac disease in an attempt to determine why some children with high-risk
genes develop T1D or celiac disease, while most remain disease-free. This
information will be used to try to prevent both diabetes and celiac disease in
children. Recently reported TEDDY research showed an association between gluten
consumption in the early years of childhood and an increased risk of celiac
disease among genetically predisposed children.
"While T1D and celiac disease share a lot
of genetic
characteristics, there are intriguing differences in the ways these
diseases develop and progress," added Dr. Rewers. "TEDDY is
contributing exciting clues for design of future trials to prevent
both T1D and
celiac disease."
T