Mild iodine deficiency during fetal/neonatal life and neuropsychological impairment in Tuscany.

The neuropsychological performance of schoolchildren living in areas with present and past iodine deficiency in Tuscany was investigated. Children were submitted to: a) block design subtest of the Wechsler Intelligence Scale for Children-Revised (WISC-R) and a modified version of the WISC-R coding subtest which evaluate the general neuropsychological and cognitive performance, independently from familial cultural background; b) simple reaction time (RT) session which evaluates the efficiency of the whole information processing and nervous transmission mechanisms. Neuropsychological performance was tested in 107 children living in Borgo a Mozzano, an area of mild iodine deficiency (IDA) with a median urinary iodine excretion (UIE) of 64 micrograms/L (mean +/- SD: 80.1 +/- 57). One hundred and six sex and age-matched children living in Marina di Pisa, an iodine sufficient coastal village of Tuscany (ISA) with a median UIE of 142 micrograms/L (mean +/- SD: 173 +/- 95) were used as controls. Tests for neuropsychological performance were performed in 57 children living in the village of Vagli, an area with past iodine deficiency (PIDA): 30 children born before iodine prophylaxis (Group 1), when the median UIE was 32 micrograms/L (mean +/- SD: 47 +/- 22), 27 children born after the institution of iodine prophylaxis (Group 2), when the median UIE was 109 micrograms/L (mean +/- SD: 130 +/- 73). Sex and age-matched ISA-children were used as controls for each group. RTs were significantly delayed (p < 0.05) in IDA than in ISA children, while block design and coding subtests showed no significant difference.(ABSTRACT TRUNCATED AT 250 WORDS)