The Research On The Functional Areas Of Brain In Abnormal Thyroid Hormone Patients With Neuropsychiatric Symptoms

Thyroid hormone (TH) plays a significant role in the growth, development andmetabolism of central nervous system. The importance of thyroid hormone on the fetus andinfant during development of the nervous system has already been recognized, but themetabolism and the impact on brain of it are still of controversies. And it is still unclearwhether the pathophysiology of thyroid dysfunction is associated with neuropsychiatricdisorders.With the increased thyroid hormone level in blood circulation, hyperthyroidismpatients often have symptoms as neuroticism, insomnia, distracted, horizontally fine tremorof both hands, brash, think too much.etc. With the decreased level of thyroid hormonelevel in blood circulation, patients with hypothyroidism patients often have symptoms asretardation, apathy, hypersomnia, memory loss, insensitive, slow motion.etc. Converselyneuropsychiatric disorders affect the diagnosis and treatment of diseases, and eventuallyresulting in vicious cycle. Therefore, this study takes adult hyperthyroidism andhypothyroidism patients as research subjects. Through functional neuroimaging perspective,we observe the brain function areas with neuropsychiatric disorders which is caused byabnormal thyroid hormone levels and provide preliminary experimental evidence todetermine the condition, prognosis, and inspiration of its pathophysiology.Part I. Research on the Functional Areas of Brain in hyperthyroidism Patientswith Neuropsychiatric SymptomsObjectives:Investigating the spontaneous brain function characteristics in resting state andexploring the relationships among emotional disorders, spontaneous brain resting activities,biochemical and biological characteristics, observing whether there is specific brainfunctional areas at abnormal thyroid hormone level. Eventually providing evidence forclinical diagnosis and treatment for hyperthyroidism. Methods:The first study chooses51initial treatment patients with untreated primaryhyperthyroidism as case group,51cases health volunteers as control group in the same period,using the Hamilton Depression Rating Scale (Hamilton Depression Scale, HAMD), HamiltonAnxiety Scale (Hamilton anxiety Scale, HAMA) to assess the degree of anxiety. Usingresting-state functional magnetic resonance imaging (resting-state fMRI, rfMRI) and localconsistency (regional homogeneity, ReHo) method to observe the differences of resting statefunctional magnetic resonance images between two groups. And brain functional area withvarious differences has been found. Then the ReHo value and anxiety in brain functional areawith differences, depression score and thyroid hormone value were used to do correlationanalysis. Moreover two-sample t test was conducted to observe ReHo value in case andcontrol groups. Represent count datas like gender, educational level, etc are used. Using thenumber of cases (percentage).Represent normally distributed continuous variables like ReHovalues, Body Mass Index(BMI), age, etc. Using mean standard deviation (x±SD)description, represent non-normally distributed variables like FT3, FT4, emotional scalevariables, etc. Using median (interquartile range), analyzing ReHo values in different degreeof anxiety depression using by different variance analysis; comparing two groups with leastsignificant difference.(LSD)(P <0.05meaning the statistically significant difference).Performing Spearman correlation analysis for ReHo value of brain areas which presentdifferences, patients’ total emotional scale score, factor scores and thyroid hormone values.Results:1. Four brain function areas with obvious differencesThrough the analysis of fMRI-ReHo method, case group present siginificant reducein the superior frontal gyrus, orbital frontal cortex, temporal pole control compared withcontrol group(P<0.05); And case group present significantly enhanced ReHo value incerebellar vermis (P<0.05).2. The differences of ReHo value in various degrees of anxiety and depressionThere was no statistically significant differences in ReHo value of four dysfunctionbrain area among the groups with different degree of depression (P>0.05).There were statistically significant differences in ReHo value of superior frontal gyrusamong groups with different degrees of anxiety(P=0.019), using LSD method to compareeach of the two groups, we can get the ratio that, probable anxiety vs anxiety: P=0.0385; probable anxiety vs obvious anxiety: P=0.0437; probable anxiety vs severe anxiety:P=0.0449; anxiety vs obvious anxiety: P=0.0385; anxiety vs severe anxiety: P=0.0399;obvious anxiety vs severe anxiety: P=0.0449. Among them serious anxiety group showsthe highest ReHo value in superior frontal gyrus, followed by probable anxietygroup; while there was no statistically significant differences in ReHo value in otherthree areas of the brain at different degree of anxiety (P>0.05).3. Correlation among the emotional score, thyroid hormones and the ReHo value offour abnormal function area in brainThe ReHo value of superior frontal gyrus was negatively correlated with FT3andFT4. And the correlation coefficients were-0.344,-0.314; the ReHo value of superiorfrontal gyrus was positively correlated with sleep disorders factor, the correlationcoefficient was0.343; the ReHo value of temporal pole was positively correlatedwith sleep disorder factors and the correlation coefficient was0.327; the ReHo value ofcerebellar vermis was negatively correlated with anxiety score and the correlationcoefficient was-0.276. Results suggested that there were relationships among abnormalbrain function area of hyperthyroidism patients, emotional disorder and thyroid hormone.Conclusion:1. The dysfunction of frontal lobe in hyperthyroidism patients may be one of thepathophysiological mechanisms of neuropsychiatric symptoms.2. The abnormal brain function area, emotional disorder and thyroid hormone werecorrelated with the occurrence and development of hyperthyroidism.3. Severe anxiety may impact the ReHo value of superior frontal gyrus as emotionalcenter or metabolic a lot.4. Depression and anxiety in patients with hyperthyroidism is associated with neuralactivity weakened of temporal lobe spontaneous.5. The cerebellum may act as a part of the emotionol regulation loop and may be oneof causes in mood disorder. PartⅡ Research on the Functional Areas of Brain in Hypothyroidism Patientswith Neuropsychiatric SymptomsObjectives:Resting state functional magnetic resonance imaging and partial coherence analysis areused to investigate whether the hypothyroidism patient in the presence of basal hasabnormalities. My case mainly explore whether there is presence of abnormal brainfunction area with low thyroid hormone levels or not and the correlations among emotionaldisorders, spontaneous brain resting activities, biochemical and biological characteristics.Eventually investigating whether there is specific brain functional area under abnormalthyroid hormone circumstances,which can provide evidence for clinical diagnosis andtreatment of hypothyroidism.Methods:The first case group was composed of29initial treatment patients with untreatedprimary hypothyroidism, and29healthy volunteers in the same period are selected ascontrol group.Through resting state functional magnetic resonance imaging (resting-statefMRI, rfMRI) and local consistency (regional homogeneity, ReHo) method, we found thedifferences between two groups in resting state functional magnetic resonance images andgot the brain region presenting differences. Data was analyzed by REST statistical analysissoftware,and the two sample t test was used to observe ReHo value both in case andcontrol groups. Performing Spearman correlation analysis for ReHo value of brain areaswhich present differences, patients’ total emotional scale score, factor scores and thyroidhormone values.Results:1. Four brain function areas with obvious differencesResting-state functional MRI data analysis by local consistency showed that therewere brain areas with significant ReHo value differences among hypothyroidismpatients; Compared with control group, case group present significant increased ReHovalue in brain areas including the cingulate gyrus, parahippocampal gyrus and inferiortemporal gyrus control (P<0.05); the brain areas of ReHo value significantly reduced inobservation group were the left superior frontal gyrus control (P<0.05).2. The differences of value of ReHo in different degrees of anxiety and depression There was no statistically significant differences in ReHo value of four dysfunctionbrain area among the groups with different degree of depression (P>0.05).There was no statistically significant differences in ReHo value of four dysfunctionbrain area among the groups with different degree of anxiety (P>0.05).3. Correlations among the emotional score, thyroid hormones and ReHo value of fourabnormal brain function areaAnterior cingulate ReHo value were significantly associated with FT4, and alsoclosely co-related to anxiety scores and grades. Anxiety score was closely related to TSH,correlation coefficient is-0.520, and P value is0.009.Conclusion:1. The dysfunction of hypothyroidism patients’ frontal lobe, hippocampus, cingulategyrus and superior frontal gyrus may be associated with the pathophysiology of brainlesions.2. Anterior cingulate abnormal spontaneous activity may partly reflect hypothyroidismpatients’ anxiety symptom and abnormal thyroid hormone related abnormal brain activitybasis.3. There is tight correlations for the patients with hypothyroidism symptoms of anxietyand thyroid stimulating hormone (TSH) levels which are abnormally severity.