Newborn study suggests that increase in congenital hypothyroidism is entirely artifactual

A new study that was prompted by recent reports of an increase in cases of congenital hypothyroidism in the United States, and aimed at assessing the incidence of this condition among Quebec newborns, suggests that the increase is entirely artifactual. CH is characterized by inadequate thyroid hormone production and is the most common cause of preventable intellectual disability. The results were published in the Journal of Clinical Endocrinology and Metabolism by Dr. Johnny Delado-y, a pediatric endocrinologist and researcher in metabolic and genetic diseases at CHU Sainte-Justine Research Center and an assistant professor of pediatrics and biochemistry at University of Montreal.

The increase in the number of cases identified may be an artifact due to changes in screening methods and results in the treatment of some children who may, in fact, not benefit from treatment. "Overly sensitive screening methods that identify mild cases of CH represent an obvious shift in neonatal screening from its original purpose, which was to identify severe cases in which the benefits from treatment would be clearly documented", Delado-y said. "This might explain why, in the United States, more than a third of children labelled as having CH on the basis of neonatal screening no longer receive treatment after four years of age."