title: Effects of Maternal Iodine Nutrition and Thyroid Status on Cognitive Development in Offspring: A Pilot Study.
abstract: OBJECTIVE
  Maternal iodine nutrition and thyroid status may influence neurocognitive development in offspring. This study investigated the effects on the intelligence quotient (IQ) of children born to mothers with different levels of iodine supplementation, with or without the administration of levothyroxine (LT4), prior to and during pregnancy.
  
  
  METHODS
  This pilot, prospective, observational study included four study groups, each comprising 15 mother-child pairs, identified on the basis of maternal histories of iodized salt consumption and LT4 treatment prior to and during pregnancy. The groups were labeled as follows: iodine (I), no iodine (no-I), iodine + LT4 (I + T4), and no iodine + LT4 (no-I + T4). IQ tests were administered to children at 6-12 years of age with the Wechsler Intelligence Scale for Children-3rd Edition (WISC-III), with full-scale IQ (FSIQ), verbal IQ (VIQ), and performance IQ (PIQ) being evaluated.
  
  
  RESULTS
  Children of I and I + T4 mothers had similar verbal, performance, and FSIQs, which were 14, 10, and 13 points higher, respectively, than children born to no-I and no-I + T4 mothers. A positive association was found between VIQ and maternal urinary iodine (β = 1.023 [confidence interval (CI) 1.003-1.043]; p = 0.028), but not with maternal free thyroxine concentrations at any stage of pregnancy. Overall, the prevalence of borderline or defective cognitive function was more than threefold higher in the children of mothers not using iodized salt than of those mothers using it (76.9% vs. 23.1%, odds ratio 7.667 [CI 2.365-24.856], χ2 = 12.65; p = 0.0001).
  
  
  CONCLUSIONS
  Neuro-intellectual outcomes in children appear to be more dependent on their mothers' nutritional iodine status than on maternal thyroid function. These results support the growing body of evidence that prenatal, mild-to-moderate iodine deficiency adversely affects cognitive development later in life, with a seemingly greater impact on verbal abilities.
authors.affiliation: 1 Department of Clinical and Experimental Medicine, University of Messina , Messina, Italy .
authors.forename: Mariacarla
authors.initials: M
authors.lastname: Moleti
authors.affiliation: 1 Department of Clinical and Experimental Medicine, University of Messina , Messina, Italy .
authors.forename: Francesco
authors.initials: F
authors.lastname: Trimarchi
authors.affiliation: 2 Department of Pediatric, Gynecological, and Biomedical Sciences, University of Messina , Messina, Italy .
authors.forename: Gaetano
authors.initials: G
authors.lastname: Tortorella
authors.affiliation: 2 Department of Pediatric, Gynecological, and Biomedical Sciences, University of Messina , Messina, Italy .
authors.forename: Alice
authors.initials: A
authors.lastname: Candia Longo
authors.affiliation: 1 Department of Clinical and Experimental Medicine, University of Messina , Messina, Italy .
authors.forename: Grazia
authors.initials: G
authors.lastname: Giorgianni
authors.affiliation: 1 Department of Clinical and Experimental Medicine, University of Messina , Messina, Italy .
authors.forename: Giacomo
authors.initials: G
authors.lastname: Sturniolo
authors.affiliation: 3 Department of Economic Sciences, University of Messina , Messina, Italy .
authors.forename: Angela
authors.initials: A
authors.lastname: Alibrandi
authors.affiliation: 1 Department of Clinical and Experimental Medicine, University of Messina , Messina, Italy .
authors.forename: Francesco
authors.initials: F
authors.lastname: Vermiglio
mesh_terms: D000328:Adult; D002648:Child; D003071:Cognition; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007361:Intelligence Tests; D007455:Iodine / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use*; D039382:Maternal Nutritional Physiological Phenomena; D010865:Pilot Projects; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D015203:Reproducibility of Results; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage; D013961:Thyroid Gland / Q000502:physiology*; D013972:Thyrotropin; D013974:Thyroxine / Q000008:administration & dosage* / Q000097:blood; D055815:Young Adult
chemical_list: D017673:Sodium Chloride, Dietary; D013972:Thyrotropin; D007455:Iodine; D013974:Thyroxine