The Auditory Threshold in a School-Age Population is Related to Iodine Intake and Thyroid Function

Abstract

The aim of this study was to determine the relationship between auditory capacity and urinary iodine, taking into account thyroid volume and function, in a population of school-age children. Audiometry was carried out in 150 children (ages 6-14 years), together with measurements of thyroid volume, thyrotropin (TSH), free T3, free T4, thyroglobulin, antiperoxidase and anti-TSH receptor antibodies, as well as iodine in a casual urine sample. Children with a TSH >5 microU/mL were excluded from the study. In the children with palpable goiter, there was an inverse relation between the auditory threshold at all frequencies and ioduria. Children with thyroglobulin values >10 ng/mL had a higher auditory threshold at all frequencies. In the children with palpable goiter and ioduria <100 microg/L, the levels of thyroglobulin and ioduria and the age accounted for 75% of the decibel (dB) variance at 2000 (Hertz), with similar results at other frequencies. The children with a thyroid sized at the >95th percentile had an odds ratio of 3.86 (95% confidence interval: 2.59-5.10) of having a threshold >20 dB. The results warn that iodine prophylaxis is needed to prevent not only goiter but also other iodine-deficiency disorders, such as involvement of the auditory threshold in school-age children.

The Role of Nutrition in Children's Neurocognitive Development, From Pregnancy Through Childhood

“…These results are consistent with the idea that specific spelling disability is a residual problem for individuals who have slow verbal and auditory processing speed and auditory short-term memory difficulties (38). Severe ID is known to result in deaf-mutism and mild ID in reductions in hearing thresholds (39,40) that can be improved by supplementation (41,42). Given that spelling is not remediated by exposure to an iodine-fortified environment in our cohort, we propose that a central auditory processing disorder influencing working memory, rather than a hearing threshold deficit, may be at work.…”

Iodine intake and prevalence of thyroid autoimmunity and autoimmune thyroiditis in children and adolescents aged between 1 and 16 years

“…The studies on children and adolescents in Andalusia, our region, published up to now have shown high goitre prevalence (between 19 and 37%), which is associated with an insufficient intake of this trace element, whereas median UIE were low within acceptable levels, between 109 and 130 mg/l (14,15,16). However, recent papers studying other Spanish regions showed an optimal iodine intake with median UIE between 150 and 200 mg/l in children older than 6 (17,18), as well as in children younger than 6 and infants (19,20), although iodized salt had not become widespread in any of the regions.…”

Improvement in iodine status of pregnant Australian women 3years after introduction of a mandatory iodine fortification programme

“…Iodine is an essential trace element for human growth and development. Inadequate iodine intake during pregnancy is of particular concern as it can result in miscarriages, still births, cretinism, and other major impairments of the fetus (Glinoer, 2007;Simpson et al, 2011;Soriguer et al, 2000;Zimmermann et al, 2008).…”