Cognitive Development in Congenital Hypothyroidism: Is Overtreatment a Greater Threat Than Undertreatment?

Abstract

Our study suggests that CHT overtreatment during the first 2 years leads to lowered cognitive outcomes at 11 years, whereas undertreatment, if not complicated by overtreatment, results in a normal cognitive development. Fast TSH normalization at initial treatment leads to above-normal development scores at a young age but does not affect IQ at age 11 years.