Language and Neurocognitive Impairments Associated with Hypothyroidism

Abstract

Introduction: Accumulating clinical evidence has indicated that hypothyroidism was associated with neurocognitive and linguistic impairments; however, these impairments were not reported in Arabic individuals. The aims of the present study were (1) to investigate the patterns of linguistic and neurocognitive impairments associated with hypothyroidism in native speakers of Jordanian Arabic and (2) to examine the accuracy of TFT in confirming a clinical diagnosis of hypothyroidism. Methods: A cross-sectional design with random recruitment of participants from targeted hypothyroid (HT) and euthyroid (ET) groups was conducted. Clinical evaluation of hypothyroidism was obtained via a structured questionnaire followed by TFT. Evaluation measures included digit span, confrontation naming, color naming, auditory and visual memory, and visual recognition tasks. The HT group comprised 36 participants including 8 males and 28 females with a ratio of 1:3.5. Their age ranged between 5.11 and 10.7 years (M = 7.7, SD = ±1.4). The ET group included an equal number of participants in terms of age and gender, their age ranged between 5.9 and 10.8 years (M = 7.6, SD = ±1.5). Results: Results revealed significant differences between the two experimental groups in all of the linguistic and neurocognitive tasks. The HT showed 10- and 26-s delayed responses on a timed color naming and visual recognition tasks compared to the ET group, whereas the ET group showed larger scores compared to the HT on the digit span, confrontation naming, auditory memory, and visual memory tasks. Differences were 2.2, 4, 1.7, and 3 points, respectively. Conclusion: Hypothyroidism influences linguistic and neurocognitive functions mainly naming ability, working memory, and auditory and visual processes needed for learning. Clinicians ought to be attentive to these impacts when designing screening and therapy protocols for children with hypothyroidism. Furthermore, TSH showed higher prediction of hypothyroidism and may be used in favor of FT3 and FT4.