Neurocognitive functions and some electroencephalographic changes in preadolescent children with different degrees of primary hypothyroidism and mild iodine deficiency

Abstract

Neurologic and electrophysiologic changes in children with mild hypothyreosis andeuthyroidgoiteratthebackgroundofmildIDarenotwellunderstoodand euthyroid goiter at the background of mild ID are not well understood atpresent.Ourgoalwastoevaluateofsomecognitivedisturbancesandal-at present. Our goal was to evaluate of some cognitive disturbances and al-terationofsomeEEGparametersinpreadolescentchildrenatearlystagesofteration of some EEG parameters in preadolescent children at early stages of thedevelopmentofprimaryhypothyreosisandeuthyroidgoiter.55somaticallythe development of primary hypothyreosis and euthyroid goiter. 55 somatically healthypreadolescentchildren,aged8-12yearswiththe1healthy preadolescent children, aged 8-12 years with the 1ststdegreeofdiffuse degree of diffuse goiterunderwentclinicalandneurologicalinvestigationofcognitivefunctions:goiter underwent clinical and neurological investigation of cognitive functions: ”copycopy”,, ”timetocopytime to copy”and and ”recognitionrecognition”usingReyComplexFigureTestand using Rey Complex Figure Test and recognitiontrialaswellasRochesterfatigueDiarytest;MotorFatigueindex,recognition trial as well as Rochester fatigue Diary test; Motor Fatigue index, PASAT–3(secondversion)andlassitudewasevaluated.Digital21channeledPASAT – 3 (second version) and lassitude was evaluated. Digital 21 channeled EEGstudywasalsoperformed.Studygroupswererandomizedto:childrenEEG study was also performed. Study groups were randomized to: children withovertmildhypothyreosis;childrenwithsubclinicalhypothyreosis;euthyroidwith overt mild hypothyreosis; children with subclinical hypothyreosis; euthyroid children;healthycontrols.MedianaofUIE64wasinthelower3children; healthy controls. Mediana of UIE 64 was in the lower 3rdrdintherange in the range formildID.Childrenofthestudygroupmoreoftenhadnon-specificneurolog-for mild ID. Children of the study group more often had non-specifi c neurolog-icsymptoms.Allindicesofneurocognitivedysfunctionweremorefrequentinic symptoms. All indices of neurocognitive dysfunction were more frequent in patients with overt hypothyreosis (P<0,001) and in lesser extent were present in subclinicalhypothyreosisandeuthyroidgoiter,comparedtocontrols.Thiswassubclinical hypothyreosis and euthyroid goiter, compared to controls. This was accompaniedbythechangesofEEGparameters.Thepathologicvisualversionaccompanied by the changes of EEG parameters. The pathologic visual version ofEEGhad90%ofchildrenwithoverthypothyreosis.Inturnedoutthatinof EEG had 90% of children with overt hypothyreosis. In turned out that in prepubertalchildrenisaccompaniedbycognitivedisordersrepresentedbyMildprepubertal children is accompanied by cognitive disorders represented by Mild CognitiveImpairment;amongneurologicsubclinicalsignsofmanifestationofCognitive Impairment; among neurologic subclinical signs of manifestation of IDtheFatiguetestisofgreatsensitivity;evenmildIDischaracterizedbyspe-ID the Fatigue test is of great sensitivity; even mild ID is characterized by spe-cificchangesofthefrequencyandamplitudeofphysiologicspectrumofEEGcifi c changes of the frequency and amplitude of physiologic spectrum of EEG activity,mainlyofaA;pathologicconsequencesofIDaremanifestedbothinactivity, mainly of aA; pathologic consequences of ID are manifested both in overtandsubclinicalhypothyroidismandinlesserextentinpatientswitheuthy-overt and subclinical hypothyroidism and in lesser extent in patients with euthyroid goiter.