Subclinical hypothyroidism increases the risk for depression in the elderly

Therapeutic potential of stilbenes in neuropsychiatric and neurological disorders: A comprehensive review of preclinical and clinical evidence

Neuropsychiatric disorders are anticipated to be a leading health concern in the near future, emphasizing an outstanding need for the development of new effective therapeutics to treat them. Stilbenes, with resveratrol attracting the most attention, are an example of multi-target compounds with promising therapeutic potential for a broad array of neuropsychiatric and neurological conditions. This review is a comprehensive summary of the current state of research on stilbenes in several neuropsychiatric and neurological disorders such as depression, anxiety, schizophrenia, autism spectrum disorders, epilepsy, traumatic brain injury, and neurodegenerative disorders. We describe and discuss the results of both in vitro and in vivo studies. The majority of studies concentrate on resveratrol, with limited findings exploring other stilbenes such as pterostilbene, piceatannol, polydatin, tetrahydroxystilbene glucoside, or synthetic resveratrol derivatives. Overall, although extensive preclinical studies show the potential benefits of stilbenes in various central nervous system disorders, clinical evidence on their therapeutic efficacy is largely missing.

Emotional and behavioral features associated with subclinical hypothyroidism in children and adolescents with Down syndrome

Background

Subclinical hypothyroidism (SH) is particularly frequent in individuals with Down syndrome (DS). Despite the amount of evidence suggesting SH is associated with psychopathological symptoms and sleep problems in general population, poor is known about the emotional and behavioral features associated with SH in children with DS.

Objective

The first aim of the current study was to investigate differences in emotional and behavioral profiles between a group of children with DS exhibiting co-occurring SH and a group of age and BMI-matched children with DS without co-occurring SH. The second aim of the present study was to investigate differences in sleep disturbances between these groups.

Methods

We included in this retrospective study 98 participants with DS aged 3-18 years with the aim to explore differences in emotional/behavioral problems as well as in sleep difficulties between children with DS with or without co-occurring SH.

Results

Participants with co-occurring SH exhibited significantly higher scores at several scales of the Conners' Parent Rating Scales Long Version - Revised. However, they did not exhibit more sleep problems than control group.

Conclusion

These results provide specific indications for psychological and neuropsychiatric evaluation of children with DS with suspected or diagnosed SH, highlighting the importance of a multidisciplinary approach in clinical care for children and adolescents with DS.

Prevalence and risk factors for subclinical hypothyroidism in older patients with major depressive disorder

BACKGROUND

Subclinical hypothyroidism (SCH) is highly correlated with major depressive disorder (MDD). However, the prevalence and risk factors for SCH in older patients with MDD have rarely been reported in China.

METHODS

This cross-sectional study included 266 older MDD patients with SCH was performed. Clinical and anthropometric, biochemical, and thyroid function data were collected. Depression, anxiety, and psychotic symptoms were assessed using the Hamilton Depression Scale, the Hamilton Anxiety Scale, and the Positive and Negative Syndrome Scale positive subscale, respectively.

RESULTS

Among older patients with MDD, the prevalence of SCH was 64.7% (172/266). Compared to patients without SCH, older MDD patients with SCH had a longer disease course and higher TSH, A-TG, A-TPO, HDL-C, LDL-C, TC, FPG, and systolic pressure levels (all P ≤ 0.002). Furthermore, disease progression (OR 1.082, 95% CI 1.020-1.147, P = 0.009), A-TG (OR 1.005, 95% CI 1.001-1.009, P = 0.017), TC (OR 2.024, 95% CI 1.213-3.377, P = 0.007), FPG (OR 2.916, 95% CI 1.637-5.194, P < 0.001), systolic pressure (OR 1.053, 95% CI 1.008-1.100, P = 0.022) were independently associated with SCH, in older patients with MDD.

CONCLUSIONS

Our findings suggest a high prevalence of SCH in older patients with MDD. Several demographic and clinical variables were independently associated with SCH in older patients with MDD.

The Impact of Hypothyroidism on the Quality of Life of Adults in Riyadh, Saudi Arabia

Background and objective Hypothyroidism is extremely common and associated with far-reaching health consequences. The negative effects of hypothyroidism on patients' quality of life (QoL) are well-documented. It is said to be common in the countries of the Arabian Gulf, although it is often misdiagnosed and treated in an inconsistent manner. Hence, understanding how an illness like this affects a patient's life might help us enhance their QoL and get us closer to the healthcare transformation goals of Saudi Arabia's Vision 2030. Methodology This cross-sectional study was conducted in Riyadh, Saudi Arabia, between June 2022 and February 2023. A convenience non-probability sampling method was used. The WHO Quality of Life (WHOQOL)-BREF questionnaire in Arabic was used to compile the data. Data were collected using a standardized form, refined using Google Forms, and then documented in an Excel spreadsheet. The descriptive statistics were shown as means and standard deviations (SD). To assess the numerical data, a t-test was used, while the chi-square test was employed to examine the relationship between the qualitative factors. Results A total of 394 adults from the general population with hypothyroidism were surveyed, including 105 men and 289 women. Of them, 151 (38.3%) patients had not sought therapy for their hypothyroidism, while 243 (61.7%) patients had. When asked about the QoL, a significant segment (37.6%) of patients reported that it was high, and 29.7% reported being totally satisfied with their health. The WHOQOL-BREF domain scores revealed that environmental health had the highest value (24.04 ±4.62), followed by physical health (22.24 ±3.23), and then psychological health (18.08 ±2.82), and the lowest scores were reported for the rate of QoL and satisfaction with health (2.64 ±1.36 and 2.80 ±1.68), respectively. Each domain of the WHOQOL-BREF had its own set of variables that differed from one another in a statistically significant manner (p<0.001). Conclusions  Based on our findings, we recommend expert physician monitoring and implementing educational programs as well as placing a greater emphasis on patients' QoL in the management of hypothyroidism.

Neuropsychiatric Manifestations of Thyroid Diseases

Thyroid disorders are known to cause neuropsychiatric manifestations. Various neuropsychiatric manifestations are depression, dementia, mania, and autoimmune Hashimoto encephalopathy. Numerous investigations carried out in the previous 50-60 years have been evaluated critically. The pathophysiology of neuropsychiatric symptoms of thyroid diseases is described in the current study and its link with autoimmune Hashimoto encephalopathy is also discussed. Furthermore, this paper also describes the association between thyroid-stimulating hormones and cognitive impairment. Hypothyroidism is associated with depression and mania, and hyperthyroidism is linked with dementia and mania. The association between Graves' disease and various mental disorders such as depressive and anxiety disorders is also discussed. The aim of this study is to review the relationship between various neuropsychiatric disorders and thyroid diseases. A literature search from the PubMed database to find various neuropsychiatric manifestations of thyroid disorders in the adult population was conducted. According to the review of the studies, cognitive impairment can result from thyroid disease. It has not been possible to demonstrate how hyperthyroidism can hasten the process of developing dementia. However, subclinical hyperthyroidism, thyroid-stimulating hormone (TSH) levels below the normal range, and high free thyroxine (T4) levels all raise the risk of dementia in the elderly. Additionally, the potential mechanisms underlying this association have been examined. A quick summary of the research on mania as a clinical symptom of hypothyroidism and its likely causes and pathogenesis is also reviewed. There is no dearth of evidence that describes various neuropsychiatric manifestation in thyroid disorders.

Assessment of Quality of Life Among Patients With Primary Hypothyroidism: A Case-Control Study

Introduction Hypothyroidism is a globally prevalent condition with a huge impact on health. It has been demonstrated that hypothyroidism is associated with negative health outcomes that have a significant impact on quality of life. The aim of this study is to assess the relative significance of various parts of quality of life satisfaction in adult patients with hypothyroidism. This study has never been done in Saudi Arabia. No previous research was conducted in our region to highlight the quality of life of these patients. From this, it is very important to acknowledge the impact of hypothyroidism on quality of life, to help improve their lives and reduce the burden of the disease. Method This is a case-control study conducted on patients with hypothyroidism presented to the family medicine clinic at King Abdulaziz University Hospital. The participants were divided into two groups: patients with primary hypothyroidism (cases) and euthyroid subjects of the same age without chronic illnesses (control group). We used the Short Form-12 questionnaire (SF-12) and a sociodemographic questionnaire as a tool to assess the quality of life. Results Compared to healthy euthyroid controls, patients with hypothyroidism had a significantly reduced quality of life regarding their physical (p<0.001) aspect, with mental health not being affected. Smoking, female gender, and BMI showed significant associations with their mental health status (p=0.021, p=0.001, and p=0.045) respectively. Conclusions Regarding the results of the current study, there is a reduced level of physical health in patients with hypothyroidism than in healthy controls, which adversely affects their QoL. Smoking, gender, and BMI were associated with lower mental health among patients with hypothyroidism, which adversely affected their quality of life. Health practices should include assessment of the quality of life, monitoring by specialized physicians, and educational programs for these patients.

Thyroid hormones regulate reelin expression in neuropsychiatric disorders

The incidence and prevalence of hypothyroidism in pregnancy have increased over the past two decades, leading to the occurrence of neuropsychiatric disorders. However, the underlying mechanisms of thyroid hormone (TH)-regulated gene expression and neuropsychiatric development during the postnatal period remain unknown. Recent achievements have shown that reelin, a large extracellular glycoprotein, plays a crucial role in neuronal migration and localization during the development of neocortex and cerebellar cortex, thereby participating in the development of neuropsychiatric diseases. Reelin-induced neuronal migration requires triiodothyronine (T3) from the deiodination of thyroxine (T4) by fetal brain deiodinases. Previous studies have reported decreased reelin levels and abnormal gene expression, which are the same as the pathological alternations in reelin-induced neuropsychiatric disorders including schizophrenia and autism. Low T3 in the fetal brain due to hypothyroxinemia during pregnancy may be detrimental to neuronal migration, leading to neuropsychiatric disorders. In this review, we focus on the reelin expression between hypothyroidism and neuropsychiatric disorders.

Improvement of depression in a patient with hypothyroidism and deiodinase polymorphism with LT3 Therapy

We report a 54‐year‐old man with treatment‐resistant depression (TRD) and hypothyroidism who responded to LT3/LT4 combination, rather than LT4 alone. He was able to discontinue all antidepressant medications eventually. Interestingly, the patient has a DIO2 polymorphism.

Pathophysiology and Clinical Features of Neuropsychiatric Manifestations of Thyroid Disease

Thyroid hormones (TH) have a cardinal role in the development of the central nervous system during embryogenesis and early infancy. However, the TH-responsive genes in the developing brain cease to respond to TH in adulthood. Nevertheless, thyroid dysfunction in adults is commonly associated with a host of cognitive and psychiatric problems. Cognitive decline, dysphoria, and depression are common manifestations of overt hypothyroidism while hyperthyroidism can cause agitation, acute psychosis, and apathy, especially in older people. Whereas levothyroxine treatment can reverse dementia in the setting of hypothyroidism, the effect of levothyroxine on depressive symptoms in subjects with subclinical hypothyroidism is controversial. The use of supraphysiologic doses of TH to treat depression refractory to antidepressant remains a viable therapeutic tool with the caveat that excessive doses of thyroid hormone to treat depression may have potentially damaging effects on other organ systems. The present communication describes the pathophysiology of neuropsychiatric manifestations of thyroid disease, including changes in neurotransmission, alterations in neuronal or glial cell gene expression, blood-brain barrier dysfunction, increased risk of cerebrovascular disease, and occasionally cerebral inflammatory disease in the context of autoimmune thyroid disease. Elucidating the molecular mechanisms of TH effect on cerebral tissue will help identify novel therapeutic targets for managing people with neuropsychiatric disorders.

Comparison of thyroid-stimulating hormone levels in adolescents with schizophrenia, bipolar disorder, unipolar depression, conduct disorders, and hyperkinetic disorders

The aim of this study was to retrospectively compare values of thyroid-stimulating hormone (TSH) in adolescent patients diagnosed with schizophrenia, bipolar disorder, unipolar depression (UNI-DEP), conduct disorders (CD), and hyperkinetic disorders.The research involved 1122 patients (718 women, 64%); aged 12 to 18 hospitalized in the Department of Adolescent Psychiatry, Medical University of Lodz. We analyzed TSH levels in the whole study population and compared it between the above-mentioned subgroups of diagnoses.Mean serum TSH concentration in the studied population (n = 1122) was 2.06 μIU/mL. The values of percentiles were as follows: 2.5th - 0.53 μIU/mL, 10th - 0.89 μIU/mL, 25th - 1.31 μIU/mL, 50th - 1.9 μIU/mL, 75th - 2.6 μIU/mL, 90th - 3.43 μIU/mL, 97.5th - 4.72 μIU/mL. TSH values were negatively correlated with patients' age (P = .00001). Patients with bipolar depression had higher TSH levels than patients with CD (P = .002). Also, when male and female groups were examined separately we found that female patients with UNI-DEP and bipolar disorder had higher TSH levels than female patients with CD (P = .001; P = .001).Our results confirm that there may be a higher prevalence of thyroid dysfunctions in bipolar and UNI-DEP subgroups among adolescents and that it is worthy to consider some kind of interventions regarding thyroid function in depressed individuals.

Identification of transcriptome alterations in the prefrontal cortex, hippocampus, amygdala and hippocampus of suicide victims

Suicide is one of the leading causes of death globally for all ages, and as such presents a very serious problem for clinicians worldwide. However, the underlying neurobiological pathology remains to a large extent unknown. In order to address this gap, we have carried out a genome-wide investigation of the gene expression in the amygdala, hippocampus, prefrontal cortex and thalamus in post-mortem brain samples obtained from 20 suicide completers and 7 control subjects. By KEGG enrichment analysis indicated we identified novel clusters of downregulated pathways involved in antigen neutralization and autoimmune thyroid disease (amygdala, thalamus), decreased axonal plasticity in the hippocampus. Two upregulated pathways were involved in neuronal death in the hippocampus and olfactory transduction in the thalamus and the prefrontal cortex. Autoimmune thyroid disease pathway was downregulated only in females. Metabolic pathways involved in Notch signaling amino acid metabolism and unsaturated lipid synthesis were thalamus-specific. Suicide-associated changes in the expression of several genes and pseudogenes that point to various functional mechanisms possibly implicated in the pathology of suicide. Two genes (SNORA13 and RNU4-2) involved in RNA processing were common to all brain regions analyzed. Most of the identified gene expression changes were related to region-specific dysregulated manifestation of genetic and epigenetic mechanisms underlying neurodevelopmental disorders (SNORD114-10, SUSd1), motivation, addiction and motor disorders (CHRNA6), long-term depression (RAB3B), stress response, major depression and schizophrenia (GFAP), signal transduction at the neurovascular unit (NEXN) and inhibitory neurotransmission in spatial learning, neural plasticity (CALB2; CLIC6, ENPP1). Some of the differentially expressed genes were brain specific non-coding RNAs involved in the regulation of translation (SNORA13). One, (PARM1) is a potential oncogene and prognostic biomarker for colorectal cancer with no known function in the brain. Disturbed gene expression involved in antigen neutralization, autoimmunity, neural plasticity, stress response, signal transduction at the neurovascular unit, dysregulated nuclear RNA processing and translation and epigenetic imprinting signatures is associated with suicide and point to regulatory non-coding RNAs as potential targets of new drugs development.

Comparison of Thyroid Hormone Levels Between Patients With Major Depressive Disorder and Healthy Individuals in China

Abnormal thyroid function in major depressive disorder (MDD) has been studied extensively, but the results still remain inconsistent. In China, few large-scale studies have investigated the differences in the levels of thyroid hormones between patients with MDD and healthy controls (HCs). In this retrospective, cross-sectional study, 535 MDD patients and 998 HCs were included. We compared the levels of thyroid hormones (FT3, FT4, and TSH) between the two groups, as well as investigated the distribution of levels of thyroid hormones within and outside normal ranges. The results showed that all the three hormones were significantly lower in MDD patients than in HCs, which was also true in different gender and age subgroups. The proportion of subjects with levels of all the three hormones outside the normal range in the MDD group was higher than that in the HC group (all p < 0.05). However, no significant difference was found in clinical/subclinical hyperthyroidism or hypothyroidism between the two groups (p > 0.05). Our study showed that the levels of thyroid hormones were lower in MDD patients, suggesting that there was an association between abnormal thyroid function and depression. The higher rate of thyroid dysfunction in MDD patients indicated the importance of regular monitoring of thyroid function.

Gray Matter and Regional Brain Activity Abnormalities in Subclinical Hypothyroidism

BACKGROUND

Subclinical hypothyroidism (SCH) brain structure and resting state of functional activity have remained unexplored.

PURPOSE

To investigate gray matter volume (GMV) and regional brain activity with the fractional amplitude of low-frequency fluctuations (fALFF) in subclinical hypothyroidism (SCH) patients before and after treatment.

MATERIAL AND METHODS

We enrolled 54 SCH and 41 age-, sex-, and education-matched controls. GMV and fALFF of SCH were compared with controls and between pre- and post-treatment within SCH group. Correlations of GMV and fALFF in SCH with thyroid function status and mood scales were assessed by multiple linear regression analysis.

RESULTS

Compared to controls, GMV in SCH was significantly decreased in Orbital part of inferior frontal, superior frontal, pre-/postcentral, inferior occipital, and temporal pole gyrus. FALFF values in SCH were significantly increased in right angular, left middle frontal, and left superior frontal gyrus. After treatment, there were no significant changes in GMV and the local brain function compared to pre-treatment, however the GMV and fALFF of the defective brain areas were improved. Additionally, decreased values of fALFF in left middle frontal gyrus were correlated with increased mood scales.

CONCLUSION

In this study we found that patients with SCH, the gray matter volume in some brain areas were significantly reduced, and regional brain activity was significantly increased. After treatment, the corresponding structural and functional deficiencies had a tendency for improvement. These changes may reveal the neurological mechanisms of mood disorder in SCH patients.

Brain structural network alterations related to serum cortisol levels in drug-naïve, first-episode major depressive disorder patients: a source-based morphometric study

Higher cortisol levels due to a hyperactive hypothalamic–pituitary–adrenal axis have been reported in patients with major depressive disorder (MDD). Increased cortisol levels change both the brain morphology and function in MDD patients. The multivariate source-based morphometry (SBM) technique has been applied to investigate neuroanatomical changes in some neuropsychiatric diseases, but not MDD. We aimed to examine the alterations in gray matter (GM) networks and their relationship with serum cortisol levels in first-episode, drug-naïve MDD patients using SBM. Forty-two patients with MDD and 39 controls were recruited via interviews. Morning serum cortisol levels were measured, and high-resolution T1-weighted imaging followed by SBM analysis was performed in all participants. The patients had significantly higher serum cortisol levels than the controls. We found two GM sources, which were significantly different between patients with MDD and controls (prefrontal network, p < .01; insula-temporal network, p < .01). Serum cortisol levels showed a statistically significant negative correlation with the loading coefficients of the prefrontal network (r = − 0.354, p = 0.02). In conclusion, increased serum cortisol levels were associated with reductions in the prefrontal network in the early stage of MDD, and SBM may be a useful approach for analyzing structural MRI data.

Association between subclinical hypothyroidism and metabolic syndrome among individuals with depression

BACKGROUND

Although the connection among low thyroid function, metabolic abnormalities, and depression is well documented, the relationship between subclinical hypothyroidism (SCH) and metabolic syndrome (MetS) in depression remains unclear. This study examined the association between SCH and MetS in a large sample with depression.

METHODS

The study analyzed 370 individuals with depression who participated in the 2014 Korea National Health and Nutrition Examination Survey. Associations between the presence of SCH and MetS were estimated after adjusting for related factors using multivariate logistic regression analysis.

RESULTS

In the 370 individuals with depression, the prevalence of SCH was 9.4% (SE = 1.6%). The prevalence of MetS was significantly higher in depressed individuals with than in those without SCH (56.3 ± 9.5% vs. 22.8 ± 2.6%; p = 0.001). After adjusting for covariates, the odds of having MetS were 7.127 times greater among depressed individuals with SCH than among those without SCH (95% confidence interval, 2.077-24.458).

LIMITATIONS

The cross-sectional study design prevented inferences regarding causality and the effects of changes in variables.

CONCLUSIONS

Depressed individuals with SCH are more likely to meet the criteria for MetS. These results highlight the significance of low thyroid function and the metabolic burden of individuals with depression.

Subclinical hypothyroidism and anxiety may contribute to metabolic syndrome in Sichuan of China: a hospital-based population study

The prevalence of Metabolic syndrome (MetS) in Sichuan of China has not yet been estimated. Meanwhile the association among anxiety, subclinical hypothyroidism (SCH) and MetS was less well-studied. The data was retrieved retrospectively from Health Promotion Center of West China Hospital database between 2014 and 2017. Internal validation by randomizing into training and testing panel by 9:1 and external validation with National Health and Nutrition Examination Survey (NHNES) were conducted. 19006 subjects were included into analysis, and 3530 (18.6%) of them were diagnosed with MetS. In training panel, age, sex (male), SCH (presence), SAS score, alcohol (Sometimes & Usual) and smoking (Active) were identified as independent risk factors for MetS, which was confirmed in testing panel internally. NHNES data validated externally the association between free thyroxine (fT4) and MetS components. The C-indices of predicting MetS nomogram were 0.705 (95% CI: 0.696–0.714) and 0.728 (95% CI: 0.701–0.754) in training and testing panel respectively. In conclusion, MetS prevalence was 18.6% in Sichuan. SCH and anxiety may be associated with MetS independently. A risk scale-based nomogram with accurate and objective prediction ability was provided for check-up practice, but more cohort validation was needed.

Thyroid Hormone Changes in Early Pregnancy Along With the COVID-19 Pandemic

PURPOSE

COVID-19 (Coronavirus Disease 2019) was first reported in December 2019 and quickly swept across China and around the world. Levels of anxiety and depression were increased among pregnant women during this infectious pandemic. Thyroid function is altered during stressful experiences, and any abnormality during early pregnancy may significantly affect fetal development and pregnancy outcomes. This study aimed to determine whether the COVID-19 pandemic induces thyroid hormone changes in early pregnant women.

METHODS

This study comprised two groups of pregnant women in Shanghai in their first trimester - those pregnant women before the COVID-19 outbreak from January 20, 2019, to March 31, 2019 (Group 1) and those pregnant during the COVID-19 outbreak from January 20, 2020, to March 31, 2020 (Group 2). All women were included if they had early pregnancy thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (TT3), and total thyroxine (TT4) concentrations, thyroid peroxidase (TPO) antibody or thyroglobulin antibody (TgAb) available and did not have a history of thyroid diseases or received thyroid treatment before or during pregnancy. We used propensity score matching to form a cohort in which patients had similar baseline characteristics.

RESULTS

Among 3338 eligible pregnant women, 727 women in Group 1 and 727 in Group 2 had similar propensity scores and were included in the analyses. Pregnant women in Group 2 had significantly higher FT3 (5.7 vs. 5.2 pmol/L, P<0.001) and lower FT4 (12.8 vs. 13.2 pmol/L, P<0.001) concentrations compared with those in Group 1. Pregnant women in Group 2 were more likely to develop isolated hypothyroxinemia (11.6% vs. 6.9%, OR, 1.75 [95% CI, 1.20-2.53], P=0.003) than those in Group 1 but had a significantly lower risk of TgAb positivity (12.0% vs. 19.0%, OR, 0.58 [95% CI, 0.43-0.78], P<0.001).

CONCLUSION

Pregnant women in their first trimester in Shanghai during the COVID-19 outbreak were at an increased risk of having higher FT3 concentrations, lower FT4 concentrations, and isolated hypothyroxinemia. The association between thyroid hormones, pregnancy outcomes, and the COVID-19 outbreak should be explored further.

Age-Related Resistance to Thyroid Hormone Action

The age-related resistance to thyroid hormones (THs) explains the paucity of symptoms and signs of hyperthyroidism in older adults and may partly explain the myriad of symptoms and signs of hypothyroidism in biochemically euthyroid older people. This review considers the available data on the mechanisms underlying TH resistance with aging and compares these physiologic changes with the changes observed in congenital TH resistance syndromes. Aging is associated with alterations in TH economy along with a host of changes in the responsiveness of various tissues to THs. The age-related resistance to THs can be attributed to decreased TH transport to tissues, decreased nuclear receptor occupancy, decreased activation of thyroxine to triiodothyronine, and alterations in TH responsive gene expression. Although an increase in serum TH levels is expected in syndromes of TH resistance, unchanged serum TH levels in the euthyroid elderly is the result of increased sensitivity to TH negative feedback with increased suppression of thyroid-stimulating hormone, decreased thyroidal sensitivity to thyroid-stimulating hormone, and decreased TH production and secretion. The current clinical evidence suggests that the age-related TH resistance is mostly an adaptive response of the aging organism. It is tempting to speculate that similar changes can occur prematurely in a group of younger people who present with signs and symptoms of hypothyroidism despite normal serum thyroid function tests.

Thyroid Related Quality of Life in Elderly with Subclinical Hypothyroidism and Improvement on Levothyroxine is Distinct from that in Young Patients (TSAGE)

The aim of this study was to investigate in a longitudinal approach whether levothyroxine (LT4) substitution has a different impact on quality of life (QoL) and thyroid related QoL in younger (<40 years) and older subjects (>60 years) with elevated thyroid-stimulating hormone (TSH) concentrations. The study included male and female patients with newly diagnosed, untreated subclinical hypothyroidism defined by TSH>8 mU/l. Patients were recruited throughout Germany from 2013-2016 and evaluated by clinical assessment, blood sampling and questionnaires for health related QoL and thyroid-disease thyroid-related QoL (ThyPRO) at time of diagnosis and six months after initiation of LT4 treatment. We found significantly lower QoL in both young and old patients with subclinical hypothyroidism compared to age-matched healthy individuals. Higher scores on follow-up were found in all patients irrespective of age, indicating better QoL on LT4 therapy. Analysis of the ThyPRO questionnaire showed that old patients experienced less Emotional Susceptibility, Tiredness, and Impaired Day Life on LT4, while young patients reported less Cognitive Complaints, Emotional Susceptibility, and Impaired Day Life compared to baseline assessment. Hypothyroidism with TSH concentrations>8 mU/l is associated with impairment in general and ThyPRO QoL in young and old age. Older patients benefited from LT4 therapy and remarkably show similar degree of improvement as younger patients, albeit with some thematic variation in ThyPRO QoL. Our data confirm current recommendations on initiation of LT4 substitution and suggest that this should not be withheld in elderly with TSH concentration above 8-10 mU/l.

Subclinical thyroid dysfunction and depressive symptoms: protocol for a systematic review and individual participant data meta-analysis of prospective cohort studies

INTRODUCTION

Prospective cohort studies on the association between subclinical thyroid dysfunction and depressive symptoms have yielded conflicting findings, possibly because of differences in age, sex, thyroid-stimulating hormone cut-off levels or degree of baseline depressive symptoms. Analysis of individual participant data (IPD) may help clarify this association.

METHODS AND ANALYSIS

We will conduct a systematic review and IPD meta-analysis of prospective studies on the association between subclinical thyroid dysfunction and depressive symptoms. We will identify studies through a systematic search of the literature in the Ovid Medline, Ovid Embase, Cochrane Central Register of Controlled Trials (CENTRAL) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases from inception to April 2019 and from the Thyroid Studies Collaboration. We will ask corresponding authors of studies that meet our inclusion criteria to collaborate by providing IPD. Our primary outcome will be depressive symptoms at the first available individual follow-up, measured on a validated scale. We will convert all the scores to the Beck Depression Inventory scale. For each cohort, we will estimate the mean difference of depressive symptoms between participants with subclinical hypothyroidism or hyperthyroidism and control adjusted for depressive symptoms at baseline. Furthermore, we will adjust our multivariable linear regression analyses for age, sex, education and income. We will pool the effect estimates of all studies in a random-effects meta-analysis. Heterogeneity will be assessed by I². Our secondary outcomes will be depressive symptoms at a specific follow-up time, at the last available individual follow-up and incidence of depression at the first, last and at a specific follow-up time. For the binary outcome of incident depression, we will use a logistic regression model.

ETHICS AND DISSEMINATION

Formal ethical approval is not required as primary data will not be collected. Our findings will have considerable implications for patient care. We will seek to publish this systematic review and IPD meta-analysis in a high-impact clinical journal.

PROSPERO REGISTRATION NUMBER

CRD42018091627.

Thyroid disorders in Brazil: the contribution of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Thyroid disorders are common diseases, both in Brazil and worldwide. The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a prospective cohort study that investigates cardiovascular diseases, diabetes, and associated factors, including non-classical cardiovascular risk factors such as thyroid function. Thyroid function was classified according to thyrotropin stimulating hormone (TSH), free thyroxine (FT4), and use of medication to treat thyroid disorders, after excluding participants who reported use of any medication that could alter the results of the TSH and FT4 tests. All analyses included in this review are cross-sectional using baseline data (2008 to 2010). The results showed an association of subclinical thyroid disorders with biomarkers of subclinical atherosclerosis, measured by carotid intima-media thickness and coronary artery calcium, insulin resistance, metabolic syndrome, and some psychiatric disorders. No association was found with the biomarker of inflammation high-sensitivity C-reactive protein, or changes in pulse wave velocity or heart rate variability.

Depression as a Neuroendocrine Disorder: Emerging Neuropsychopharmacological Approaches beyond Monoamines

Depression is currently recognized as a crucial problem in everyday clinical practice, in light of ever-increasing rates of prevalence, as well as disability, morbidity, and mortality related to this disorder. Currently available antidepressant drugs are notoriously problematic, with suboptimal remission rates and troubling side-effect profiles. Their mechanisms of action focus on the monoamine hypothesis for depression, which centers on the disruption of serotonergic, noradrenergic, and dopaminergic neurotransmission in the brain. Nevertheless, views on the pathophysiology of depression have evolved notably, and the comprehension of depression as a complex neuroendocrine disorder with important systemic implications has sparked interest in a myriad of novel neuropsychopharmacological approaches. Innovative pharmacological targets beyond monoamines include glutamatergic and GABAergic neurotransmission, brain-derived neurotrophic factor, various endocrine axes, as well as several neurosteroids, neuropeptides, opioids, endocannabinoids and endovanilloids. This review summarizes current knowledge on these pharmacological targets and their potential utility in the clinical management of depression.

Subclinical Hypothyroidism and Depression: A Systematic Review and Meta-Analysis

Background: Thyroid function is closely associated with neuropsychological functions, including mental state and cognitive functions. Although thyroid function is routinely examined in persons with depressive symptom, the association between subclinical hypothyroidism (SCH) and depression remains inconclusive. Objective: This systematic review and meta-analysis aimed to evaluate the risk of depression in persons with SCH. Methods: The PubMed, Embase, and Web of Science databases were searched up to August 2018. The primary outcome was the prevalence of depression, as evaluated by various types of self-reported depression scales. Odds ratios (ORs) were calculated to compare the risk of depression between persons with SCH and those with euthyroidism. Results: Twenty-one studies were included in the systematic review, with a total of 103,375 subjects from 7 studies being pooled for the meta-analysis to evaluate the risk of depression. The meta-analysis showed that persons with SCH had a significantly elevated risk of depression than persons with euthyroidism (OR = 1.78, 95% confidence interval [CI]: 1.11-2.86, P = 0.02). No publication bias was found, as indicated by Egger's test (t = -0.49, P = 0.647) and Begg's test (z = -0.15, P = 0.881). In addition, the funnel plot showed a symmetric distribution. Conclusions: This meta-analysis demonstrated that SCH was positively associated with the risk of depression, especially in persons above 50 years of age, suggesting it is necessary to pay close attention to depressive symptoms in persons with SCH.

Association between subclinical thyroid dysfunction and depressive symptoms in the Korean adult population: The 2014 Korea National Health and Nutrition Examination Survey

BACKGROUND

Clinical hyper and hypothyroidism are associated with a risk for depression.

OBJECTIVES

This study was performed to investigate the association between depressive symptoms and subclinical thyroid dysfunction.

METHODS

Among the 7,550 subjects who participated in the 2014 Korea National Health and Nutrition Examination Survey, 1,763 participants without overt thyroid disease were included in this study. Serum thyroid stimulating hormone (TSH), serum free thyroxine (fT4), and depressive symptoms were analyzed based on the Patient Health Questionnaire (PHQ9).

RESULTS

The percentages of subjects with subclinical hypothyroidism and subclinical hyperthyroidism were 3.3% and 2.6%, respectively. The percentages of subjects with moderate (10-14 points), moderately severe (15-19 points), and severe (≥20 points) depression according to the distribution of PHQ-9 scores were 4.7%, 1.1%, and 0.3%, respectively. TSH, fT4, and the percentage of patients with subclinical hypothyroidism were not significantly associated with PHQ-9 score. However, the percentage of patients with subclinical hyperthyroidism increased significantly with PHQ9 score (P = 0.002). Subjects with subclinical hyperthyroidism had higher PHQ-9 scores than those with normal thyroid function (mean ± standard error [SE], 4.2 ± 0.5 vs. 2.7 ± 0.1 points, P = 0.010). More subjects with subclinical hyperthyroidism had a PHQ9 score ≥ 10 than did those with normal thyroid function (mean ± SE, 17.1 ± 3.5 vs. 5.8 ± 0.6%, P = 0.005). We performed logistic regression analyses for the presence of depressive symptoms, using age, sex, education, household income, alcohol drinking, smoking, diabetes, cerebrovascular disease history, subclinical hypothyroidism, and subclinical hyperthyroidism as variables. Subclinical hyperthyroidism was associated with the presence of clinically relevant depression (PHQ9 score ≥ 10), (odds ratio [OR], 4.04; 95% confidence interval [CI], 1.75-9.31; P = 0.001), and clinically significant depression (PHQ9 score ≥ 15), (OR, 7.05; 95% CI, 1.67-29.67; P = 0.008), respectively. However, subclinical hypothyroidism was not associated with the presence of clinically relevant depression (OR, 1.15; 95% CI, 0.39-3.38; P = 0.800), or clinically significant depression (OR, 3.35; 95% CI, 0.71-15.79; P = 0.127).

CONCLUSIONS

We demonstrated that subclinical hyperthyroidism was independently associated with depressive symptoms in the Korean general population using national cross-sectional data.

Subclinical Hypothyroidism and Incident Depression in Young and Middle-Age Adults

BACKGROUND

The role of subclinical hypothyroidism in the development of depression remains controversial. We examined the prospective association between subclinical hypothyroidism and incident depressive symptoms.

METHODS

We conducted a prospective cohort study of 220,545 middle-age adults without depression who had undergone at least two comprehensive health examinations between 1 January 2011 and 31 December 2014. Thyroid-stimulating hormone, free triiodothyronine (FT3), and free thyroxine (FT4) levels were measured using an electrochemiluminescent immunoassay. The study outcome was incident depressive symptoms, defined as a Center for Epidemiologic Studies-Depression score >16.

RESULTS

During a median follow-up period of 2 years, incident depressive symptoms occurred in 7323 participants. The multivariable-adjusted hazard ratio for incident depressive symptoms comparing subclinical hypothyroid and euthyroid participants was 0.97 (95% confidence interval, 0.87 to 1.09). Similarly, among euthyroid participants (n = 87,822), no apparent association was found between thyroid hormone levels and an increased risk of incident depressive symptoms.

CONCLUSIONS

No apparent association was found between subclinical hypothyroidism and incident depressive symptoms in a large prospective cohort of middle-age men and women.

Expression levels of interferon-ɣ and type 2 deiodinase in patients diagnosed with recurrent depressive disorders

BACKGROUND

Thyroid hormones (TH) are involved in modulation of the immune system and inflammation. TH dysregulation is associated with depressive disorders. The iodothyronine deiodinases (DIOs), the key enzymes for TH synthesis, can be affected and induced by pro-inflammatory cytokines. We aimed to investigate the levels of and correlation between type 2 DIO (DIO2) and interferon-gamma (IFN-ɣ) in patients with recurrent depressive disorders (rDD).

METHODS

Data from 91 rDD patients and 105 healthy controls were analyzed. The diagnoses are based on the ICD-10 criteria (F33.0-F33.8). Expression levels of DIO2 and IFN-ɣ were estimated using the method based on the polymerase chain reaction and the enzyme-linked immunosorbent assay (ELISA).

RESULTS

The DIO2 expression on mRNA/protein levels in rDD patients (both female and males) was reduced as compared with the control subjects. No correlation between DIO2 and IFN-ɣ expression was observed.

CONCLUSION

This is the first study to reveal that one may cautiously suggest that DIO2 may be involved in the development and/or progression of rDD. The mechanisms of TH regulation on depression, however, need further investigation.

Low fT3 is associated with diminished health-related quality of life in patients with acute coronary syndrome treated with drug-eluting stent: a longitudinal observational study

Acute coronary syndrome (ACS) patients with low triiodothyronine (T3) syndrome characterized by low free T3 (fT3) levels with normal thyroxine (T4) and thyroid-stimulating hormone (TSH) have a higher rate of death. The impact of fT3 on Health related quality of life (HRQOL) in patients with ACS is still unknown. 528 ACS patients treated with drug-eluting stent (DES) were included in this prospective, observational study. Patients were classified into low fT3 group (n=126) and normal fT3 group (n=402) according to serum fT3 level. Every patient was prospectively interviewed at baseline and 1 year following percutaneous coronary intervention (PCI). HRQOL was assessed with the use of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Low fT3 patients had poorer HRQOL than normal fT3 patients both at baseline and 1-year follow-up (all p<0.05). During 1-year follow-up, HRQOL scores for all patients were significantly higher than baseline. Low fT3 patients had lesser gains in physical functioning, bodily pain, general health, vitality, social functioning and role emotional (all p<0.05). Generally, low fT3 patients demonstrated less improvement in Physical Component Score (PCS) (p=0.008) and Mental Component Score (MCS) (p=0.001). The percentage of patients reaching MCID for PCS and MCS was lower in low fT3 group than that in normal fT3 group (p<0.001). Multivariate linear regression analyses showed that low level of fT3 was an independent risk factor for PCS and MCS improvements. In conclusion, a low fT3 level is a predictor of worse HRQOL improvement in ACS patients treated with DES.

Increased aggression and lack of maternal behavior in Dio3-deficient mice are associated with abnormalities in oxytocin and vasopressin systems

Thyroid hormones regulate many aspects of brain development and function, and alterations in the levels of thyroid hormone action lead to abnormal anxiety- and depression-like behaviors. A complement of factors in the brain function independently of circulating levels of hormone to strictly controlled local thyroid hormone signaling. A critical factor is the type 3 deiodinase (DIO3), which is located in neurons and protects the brain from excessive thyroid hormone. Here, we examined whether a local increase in brain thyroid hormone action secondary to DIO3 deficiency is of consequence for social behaviors. Although we did not observe alterations in sociability, Dio3-/- mice of both sexes exhibited a significant increase in aggression-related behaviors and mild deficits in olfactory function. In addition, 85% of Dio3-/- dams manifested no pup-retrieval behavior and increased aggression toward the newborns. The abnormal social behaviors of Dio3-/- mice were associated with sexually dimorphic alterations in the physiology of oxytocin (OXT) and arginine vasopressin (AVP), 2 neuropeptides with important roles in determining social interactions. These alterations included low adult serum levels of OXT and AVP, and an abnormal expression of Oxt, Avp and their receptors in the neonatal and adult hypothalamus. Our results demonstrate that DIO3 is essential for normal aggression and maternal behaviors, and indicate that abnormal local regulation of thyroid hormone action in the brain may contribute to the social deficits associated with neurodevelopmental disorders.

Molecular Mechanisms Underlying the Anti-depressant Effects of Resveratrol: a Review

Major depression is a public health problem, affecting 121 million people worldwide. Patients suffering from depression present high rates of morbidity, causing profound economic and social impacts. Furthermore, patients with depression present cognitive impairments, which could influence on treatment adherence and long-term outcomes. The pathophysiology of major depression is not completely understood yet but involves reduced levels of monoamine neurotransmitters, bioenergetics, and redox disturbances, as well as inflammation and neuronal loss. Treatment with anti-depressants provides a complete remission of symptoms in approximately 50% of patients with major depression. However, these drugs may cause side effects, as sedation and weight gain. In this context, there is increasing interest in studies focusing on the anti-depressant effects of natural compounds found in the diet. Resveratrol is a polyphenolic phytoalexin (3,4',5-trihydroxystilbene; C₁₄H₁₂O₃; MW 228.247 g/mol) and has been found in peanuts, berries, grapes, and wine and induces anti-oxidant, anti-inflammatory, and anti-apoptotic effects in several mammalian cell types. Resveratrol also elicits anti-depressant effects, as observed in experimental models using animals. Therefore, resveratrol may be viewed as a potential anti-depressant agent, as well as may serve as a model of molecule to be modified aiming to ameliorate depressive symptoms in humans. In the present review, we describe and discuss the anti-depressant effects of resveratrol focusing on the mechanism of action of this phytoalexin in different experimental models.

High levels of Nesfatin-1 in relation to the dysfunction of the hypothalamic-pituitary-adrenal and hypothalamus-pituitary-thyroid axes in depressed patients with subclinical hypothyroidism

Despite the increasing amount of evidence suggesting a relationship between depression and subclinical hypothyroidism (SCH), the exact mechanism underlying this relationship remains unclear. The main purpose of this study was to investigate the roles of plasma Nesfatin-1 levels and dysfunction of the hypothalamic-pituitary-adrenal (HPA) and hypothalamus-pituitary-thyroid (HPT) axes in the comorbidity of depression and SCH. Dysfunctions of the HPA and HPT axes were detected by measuring plasma corticosterone and thyroid-stimulating hormone (TSH) concentrations, respectively. Subjects in the patient group were selected from patients hospitalized at the Anhui Mental Health Center, and subjects in the control group were recruited from healthy volunteers. Healthy control subjects were matched to the patients in terms of weight and body mass index. The Hamilton Depression Rating Scale was administered to both the groups. The enzyme-linked immunosorbent assay method was used to measure plasma Nesfatin-1, corticosterone, and TSH levels. A radioimmunoassay kit was used for the measurement of the plasma-free triiodothyronine and plasma-free thyroxine. The results showed that the Hamilton Depression Rating Scale scores and average Nesfatin-1, corticosterone, and TSH levels were significantly higher in depressed patients with SCH than in the control group. Moreover, positive relationships were observed between Nesfatin-1 levels and the concentrations of corticosterone (r=0.626, P<0.001) and TSH (r=0.229, P=0.036) in depressed patients with SCH. These findings indicate that Nesfatin-1 is involved in the comorbidity of depression and SCH, and the mechanism underlying this involvement might be related to the dysfunction of the HPA and HPT axes.

Depression and Hypothyroidism in a Population-Based Study of Iranian Women

Background. Recent biochemical and physiological investigations have focused on the fundament of mood disorders in thyroid dysfunction. The present study aimed to address depressive disorder in a sample of Iranian hypothyroid women compared to euthyroid individuals.

Methods. Thirty consecutive hypothyroid female patients aged 25 to 40 years who referred to the Endocrinology and Metabolism Clinic at Rasoul-e-Akram Hospital in Tehran within a four-month period in 2015 were assessed. Thirty healthy euthyroid subjects matched for sex, age, and educational level were selected as the control. For assessment of depression status, Depression Anxiety Stress Scale-21 (DASS-21) was employed.

Results. The study showed higher mean depression score in hypothyroid patients when compared to euthyroid ones (13.8 ± 9.5 versus 5.8 ± 5.2, p = 0.010). No significant association was revealed between mean depression score and patients’ education level (p = 0.627), age (p = 0.967), occupation status (p = 0.211), and marital status (p = 0.556).

Conclusion. Hypothyroid women are predisposed to depressive symptoms independent of their baseline demographic and socioeconomic characteristics.

Decreased anxiety- and depression-like behaviors and hyperactivity in a type 3 deiodinase-deficient mouse showing brain thyrotoxicosis and peripheral hypothyroidism

Hypo- and hyperthyroid states, as well as functional abnormalities in the hypothalamic-pituitary-thyroid axis have been associated with psychiatric conditions like anxiety and depression. However, the nature of this relationship is poorly understood since it is difficult to ascertain the thyroid status of the brain in humans. Data from animal models indicate that the brain exhibits efficient homeostatic mechanisms that maintain local levels of the active thyroid hormone, triiodothyronine (T3) within a narrow range. To better understand the consequences of peripheral and central thyroid status for mood-related behaviors, we used a mouse model of type 3 deiodinase (DIO3) deficiency (Dio3 -/- mouse). This enzyme inactivates thyroid hormone and is highly expressed in the adult central nervous system. Adult Dio3 -/- mice exhibit elevated levels of T3-dependent gene expression in the brain, despite peripheral hypothyroidism as indicated by low circulating levels of thyroxine and T3. Dio3 -/- mice of both sexes exhibit hyperactivity and significantly decreased anxiety-like behavior, as measured by longer time spent in the open arms of the elevated plus maze and in the light area of the light/dark box. During the tail suspension, they stayed immobile for a significantly shorter time than their wild-type littermates, suggesting decreased depression-like behavior. These results indicate that increased thyroid hormone in the brain, not necessarily in peripheral tissues, correlates with hyperactivity and with decreases in anxiety and depression-like behaviors. Our results also underscore the importance of DIO3 as a determinant of behavior by locally regulating the brain levels of thyroid hormone.

Subclinical Hypothyroidism after 131I-Treatment of Graves' Disease: A Risk Factor for Depression?

Objectives

Although it is well accepted that there is a close relationship between hypothyroidism and depression, previous studies provided inconsistent or even opposite results in whether subclinical hypothyroidism (SCH) increased the risk of depression. One possible reason is that the etiology of SCH in these studies was not clearly distinguished. We therefore investigated the relationship between SCH resulting from ¹³¹I treatment of Graves’ disease and depression.

Design And Methods

The incidence of depression among 95 patients with SCH and 121 euthyroid patients following ¹³¹I treatment of Graves’ disease was studied. The risk factors of depression were determined with multivariate logistic regression analysis. Thyroid hormone replacement therapy was performed in patients with thyroid-stimulating hormone (TSH) levels exceeding 10 mIU/L.

Results

Patients with SCH had significantly higher Hamilton Depression Scale scores, serum TSH and thyroid peroxidase antibody (TPOAb) levels compared with euthyroid patients. Multivariate logistic regression analysis revealed SCH, Graves’ eye syndrome and high serum TPO antibody level as risk factors for depression. L-thyroxine treatment is beneficial for SCH patients with serum TSH levels exceeding 10 mIU/L.

Conclusions

The results of the present study demonstrated that SCH is prevalent among ¹³¹I treated Graves’ patients. SCH might increase the risk of developing depression. L-thyroxine replacement therapy helps to resolve depressive disorders in SCH patients with TSH > 10mIU/L. These data provide insight into the relationship between SCH and depression.

Subclinical thyroid dysfunction and psychiatric disorders: cross-sectional results from the Brazilian Study of Adult Health (ELSA-Brasil)

OBJECTIVE

To evaluate the association between subclinical thyroid dysfunction and psychiatric disorders using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

DESIGN

Cross-sectional study.

PATIENTS

The study included 12 437 participants from the ELSA-Brasil with normal thyroid function (92·8%), 193 (1·4%) with subclinical hyperthyroidism and 784 (5·8%) with subclinical hypothyroidism, totalling 13 414 participants (50·6% of women).

MEASUREMENTS

The mental health diagnoses of participants were assessed by trained raters using the Clinical Interview Schedule - Revised (CIS-R) and grouped according to the International Classification of Diseases 10 (ICD-10). Thyroid dysfunction was assessed using TSH and FT4 as well as routine use of thyroid hormones or antithyroid medications. Logistic models were presented using psychiatric disorders as the dependent variable and subclinical thyroid disorders as the independent variable. All logistic models were corrected for multiple comparisons using Bonferroni correction.

RESULTS

After multivariate adjustment for possible confounders, we found a direct association between subclinical hyperthyroidism and panic disorder odds ratio [OR], 2·55; 95% confidence Interval (95% CI), 1·09-5·94; and an inverse association between subclinical hypothyroidism and generalized anxiety disorder (OR, 0·75; 95% CI, 0·59-0·96). However, both lost significance after correction for multiple comparisons.

CONCLUSION

Subclinical hyperthyroidism was positively associated with panic disorder and negatively associated with anxiety disorder, although not significant after adjustment for multiple comparisons.

Subclinical Thyroid Dysfunction and Depressive Symptoms among the Elderly: A Prospective Cohort Study

BACKGROUND

Subclinical hypothyroidism has been associated with depressive symptoms in cross-sectional studies, but prospective data and data on subclinical hyperthyroidism are scarce.

METHODS

In the Leiden substudy of the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER), thyroid-stimulating hormone and free T4 levels were measured at baseline and repeated after 6 months in adults aged 70-82 years with preexisting cardiovascular disease or known cardiovascular risk factors to define persistent thyroid functional status. Main outcome measures were depressive symptoms, assessed with the Geriatric Depression Scale 15 (GDS-15) at baseline and after 3 years. All analyses were adjusted for age, gender and education.

RESULTS

In 606 participants (41% women; mean age 75 years) without antidepressant medication, GDS-15 scores at baseline did not differ for participants with subclinical hypothyroidism (n = 47; GDS-15 score 1.75, 95% CI 1.29-2.20, p = 0.53) or subclinical hyperthyroidism (n = 13; GDS-15 score 1.64, 95% CI 0.78-2.51, p = 0.96) compared to euthyroid participants (n = 546; mean GDS-15 score 1.60, 95% CI 1.46-1.73). After 3 years, compared to the euthyroid participants, changes in GDS-15 scores did not differ for participants with subclinical hypothyroidism (x0394;GDS-15 score -0.03, 95% CI -0.50 to 0.44, p = 0.83), while subclinical hyperthyroidism was associated with an increase in GDS scores (x0394;GDS-15 score 1.13, 95% CI 0.32-1.93, p = 0.04). All results were similar for persistent subclinical thyroid dysfunction.

CONCLUSIONS

In this largest prospective study on the association of persistent subclinical thyroid dysfunction and depression, subclinical hypothyroidism was not associated with increased depressive symptoms among older adults at high cardiovascular risk. Persistent subclinical hyperthyroidism might be associated with increased depressive symptoms, which requires confirmation in a larger prospective study.

Is there Progress? An Overview of Selecting Biomarker Candidates for Major Depressive Disorder

Major depressive disorder (MDD) contributes to a significant worldwide disease burden, expected to be second only to heart disease by 2050. However, accurate diagnosis has been a historical weakness in clinical psychiatry. As a result, there is a demand for diagnostic modalities with greater objectivity that could improve on current psychiatric practice that relies mainly on self-reporting of symptoms and clinical interviews. Over the past two decades, literature on a growing number of putative biomarkers for MDD increasingly suggests that MDD patients have significantly different biological profiles compared to healthy controls. However, difficulty in elucidating their exact relationships within depression pathology renders individual markers inconsistent diagnostic tools. Consequently, further biomarker research could potentially improve our understanding of MDD pathophysiology as well as aid in interpreting response to treatment, narrow differential diagnoses, and help refine current MDD criteria. Representative of this, multiplex assays using multiple sources of biomarkers are reported to be more accurate options in comparison to individual markers that exhibit lower specificity and sensitivity, and are more prone to confounding factors. In the future, more sophisticated multiplex assays may hold promise for use in screening and diagnosing depression and determining clinical severity as an advance over relying solely on current subjective diagnostic criteria. A pervasive limitation in existing research is heterogeneity inherent in MDD studies, which impacts the validity of biomarker data. Additionally, small sample sizes of most studies limit statistical power. Yet, as the RDoC project evolves to decrease these limitations, and stronger studies with more generalizable data are developed, significant advances in the next decade are expected to yield important information in the development of MDD biomarkers for use in clinical settings.

Resveratrol Ameliorates the Anxiety- and Depression-Like Behavior of Subclinical Hypothyroidism Rat: Possible Involvement of the HPT Axis, HPA Axis, and Wnt/β-Catenin Pathway

Metabolic disease subclinical hypothyroidism (SCH) is closely associated with depression-like behavior both in human and animal studies, and our previous studies have identified the antidepressant effect of resveratrol (RES) in stressed rat model. The aim of this study was to investigate whether RES would manifest an antidepressant effect in SCH rat model and explore the possible mechanism. A SCH rat model was induced by hemi-thyroid electrocauterization, after which the model rats in the RES and LT4 groups received a daily intragastric injection of RES at the dose of 15 mg/kg or LT4 at the dose of 60 μg/kg for 16 days. The rats' plasma concentrations of thyroid hormones were measured. Behavioral performance and hypothalamic-pituitary-adrenal (HPA) activity were evaluated. The protein expression levels of the Wnt/β-catenin in the hippocampus were detected by western blot. The results showed that RES treatment downregulated the elevated plasma thyroid-stimulating hormone concentration and the hypothalamic mRNA expression of thyrotropin-releasing hormone in the SCH rats. RES-treated rats showed increased rearing frequency and distance in the open-field test, increased sucrose preference in the sucrose preference test, and decreased immobility in the forced swimming test compared with SCH rats. The ratio of the adrenal gland weight to body weight, the plasma corticosterone levels, and the hypothalamic corticotrophin-releasing hormone mRNA expression were reduced in the RES-treated rats. Moreover, RES treatment upregulated the relative ratio of phosphorylated-GSK3β (p-GSK3β)/GSK3β and protein levels of p-GSK3β, cyclin D1, and c-myc, while downregulating the relative ratio of phosphorylated-β-catenin (p-β-catenin)/β-catenin and expression of GSK3β in the hippocampus. These findings suggest that RES exerts anxiolytic- and antidepressant-like effect in SCH rats by downregulating hyperactivity of the HPA axis and regulating both the HPT axis and the Wnt/β-catenin pathway.

The significance of an isolated elevated TSH level in a depressed patient: a clinical commentary

OBJECTIVE

To discuss the approach to the isolated finding of an elevated thyrotropin (TSH) level on routine biochemical screening of a depressed patient.

METHOD

A focused literature review as well as discussion of published clinical guidelines and the formulation of a rational clinical approach.

RESULTS

Screening for thyroid dysfunction is part of the routine assessment of the depressed patient. It is not uncommon for such patients to have an isolated elevation of TSH levels with nor laboratory or clinical features of thyroid disease. There is often misunderstanding about how to deal with this isolated laboratory finding which can lead to unnecessary investigation and treatment.

CONCLUSIONS

A rational approach to evaluation and management of an isolated elevated TSH level is suggested.

Depressive symptoms in patients with subclinical hypothyroidism--the effect of treatment with levothyroxine: a double-blind randomized clinical trial

Despite the increasing evidence for relationships between thyroid dysfunction and neuropsychiatric alterations, the effect of treatment of thyroid disease on various clinical psychiatric outcomes is controversial. The purpose of this study was to investigate the effect of levothyroxine treatment on depressive symptoms in subjects with subclinical hypothyroidism. A randomized double-blind placebo-controlled clinical trial was performed. Sixty subjects (51 females and 9 males) with subclinical hypothyroidism were enrolled. Beck Depression Inventory was completed for all participants at the beginning of the study and 12 weeks after enrollment. The intervention and control groups received levothyroxine and placebo, respectively, for 12 weeks. There were no statistical differences in the total depression score and its subscales between the two groups at the beginning of the study. The Beck Depression Inventory score decreased from 16.79 ± 13.25 to 12.37 ± 10.01 (p value = 0.04) in the intervention group. The change in score was not significant for the control group (13.77 ± 11.71 to 11.86 ± 10.71; p value= 0.16). The affective subscale of Beck Depression Inventory did not change after 12 weeks of treatment with levothyroxine, while somatic subscale remarkably improved in the intervention group (p value = 0.02). This study showed the efficacy of treatment of subclinical hypothyroidism in people with levothyroxine in relation to depressive symptoms.

Association between increased serum thyrotropin concentration and the oldest old: what do we know?

To assess studies that evaluate the relation between serum thyrotropin concentration, very old subjects, and their events. We searched the PubMed, SciELO, and LILACS databases for articles published between 2004 and 2012. Our search was restricted to studies involving humans aged 65 years or older, and written in English, Spanish, or Portuguese. Studies that evaluated the association between elevated serum thyrotropin concentration among elderly subjects with subclinical hypothyroidism were chosen since at least in part they included a subpopulation of individuals aged 80 years and above. Thirteen studies were selected. No significant increase in risk of cardiovascular events, coronary heart disease, or total mortality was observed. Elevated thyrotropin concentration was associated with longevity. More randomized controlled trials are required to better define the potential benefits of elevated thyrotropin concentration in this oldest old population, hormone replacement, and longevity.

Well-being and depression in individuals with subclinical hypothyroidism and thyroid autoimmunity - a general population study

BACKGROUND

The association between subclinical hypothyroidism (SCH), with and without raised thyroid peroxidase antibodies (anti-TPO), and well-being or depression is still controversial, in spite of many studies on the topic.

AIMS

In this large general population study of 8214 individuals, we aim to clarify the significance of elevated levels of anti-TPO as a marker of poor well-being and depression in euthyroid individuals and individuals with SCH.

METHODS

In participants from the Danish General Suburban Population Study (GESUS), serum thyroid stimulating hormone (TSH), total triiodothyronine (tT3), free thyroxine (fT4) and anti-TPO was measured. Prevalence of poor well-being and depression was measured using the WHO-5 Well-being questionnaire and WHO MDI [Major (ICD-10) Depression Inventory] questionnaire.

RESULTS

Raw score for well-being or depression overall and stratified for sex was not more significantly different in euthyroid individuals than in individuals with SCH, with or without high anti-TPO, except that euthyroid women with elevated anti-TPO had better well-being (P = 0.03) compared with euthyroid women with anti-TPO within the reference range.

CONCLUSION

Elevated anti-TPO levels cannot be used as a general marker of poor well-being or depression in the general population.

Depressive symptoms and major depressive disorder in patients affected by subclinical hypothyroidism: a cross-sectional study

The relationship between subclinical hypothyroidism and depression is still controversial. Our objective was to compare the prevalence of depressive symptoms and major depressive disorder in a population of patients affected by subclinical hypothyroidism and a control group without thyroid disease. The authors enrolled 123 consecutive outpatients affected by subclinical hypothyroidism undergoing follow-up at the endocrinology department of San Paolo Hospital in Milan and 123 controls without thyroid disease under the charge of general physicians.All patients and controls underwent an evaluation by means of a psychiatric interview; Hamilton Rating Scale for Depression (HAM-D); Montgomery-Asberg Depression Rating Scale (MADRS); and serum thyroid stimulating hormone, free T4, and free T3 levels. Patients were also screened for thyroid peroxidase antibodies and thyroglobulin antibodies. Patients affected by subclinical hypothyroidism had a prevalence of depressive symptoms of 63.4% at HAM-D and 64.2% at MADRS; 22 patients (17.9%) had a diagnosis of depressive episode (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria). The control group had a prevalence of depressive symptoms of 27.6% at HAM-D and 29.3% at MADRS, and only seven controls had a diagnosis of depressive episode. The prevalence of depressive symptoms between these two groups was statistically different. This study underlines a strong association between subclinical hypothyroidism and depressive symptoms, which could have some important diagnostic and therapeutic implications in the clinical practice.

Level of thyroid-stimulating hormone (TSH) in patients with acute schizophrenia, unipolar depression or bipolar disorder

The aim of this study is to investigate differences in thyroid-stimulating hormone (TSH) level in patients with acute schizophrenia, unipolar depression, bipolar depression and bipolar mania. Serum level of TSH was measured in 1,685 Caucasian patients (1,064 women, 63.1%; mean age 46.4). Mean serum TSH concentration was: schizophrenia (n = 769) 1.71 μIU/mL, unipolar depression (n = 651) 1.63 μIU/mL, bipolar disorder (n = 264) 1.86 μIU/mL, bipolar depression (n = 203) 2.00 μIU/mL, bipolar mania (n = 61) 1.38 μIU/mL (H = 11.58, p = 0.009). Depending on the normal range used, the overall rate of being above or below the normal range was 7.9-22.3% for schizophrenia, 13.9-26.0% for unipolar depression, 10.8-27.6% for bipolar disorder, 12.2-28.5% for bipolar depression, and 11.4-24.5% for bipolar mania. We have also found differences in TSH levels between the age groups (≤20, >20 years and ≤40, >40 years and ≤60 years and >60 years). TSH level was negatively correlated with age (r = -0.23, p < 0.001). Weak correlations with age have been found in the schizophrenia (r = -0.21, p < 0.001), unipolar depression (r = -0.23, p < 0.001), bipolar depression (r = -0.25, p = 0.002) and bipolar disorder (r = -0.21, p = 0.005) groups. Our results confirm that there may be a higher prevalence of thyroid dysfunctions in patients with mood disorders (both unipolar and bipolar) and that these two diagnostic groups differ in terms of direction and frequency of thyroid dysfunctions.

Depression-like behavior in subclinical hypothyroidism rat induced by hemi-thyroid electrocauterization

The purpose of this study was to investigate the depression-like behavior performances of subclinical hypothyroidism (SCH) rat. SCH rat model was induced by hemi-thyroid electrocauterization, and the behavior performances were measured by sucrose preference test, force swimming test (FST), and tail suspension test (TST). SCH rat model was established successfully by hemi-thyroid electrocauterization. In the behavior tasks, SCH rats displayed depression-like behavior were indicated as a significant elevation of immobility time in both the TST and FST, though the sucrose preference was not significantly decreased. The index of left adrenal cortex in both SCH and clinical hypothyroidism (CH) group significantly increased, and many large lipid vacuoles were observed in the zona fasciculata cells. The serum corticosterone concentration and hypothalamic corticotropin-releasing hormone mRNA expression 2 h after behavior test was markedly up-regulated in CH rats, but not SCH rats, indicated that SCH induced a less impairment of HPA axis than CH did. The important finding of this study was that the concentration of hippocampal T3 was lower in SCH group than that of the sham group. Furthermore, the results of Pearson correlation test showed that the immobility behaviors in TST and FST were both negatively correlated with hippocampal T3 concentration. Taking together, our results indicated that SCH could result in depression-like behavior, accompanied with subtle hyperactivity of HPA axis. The reduced hippocampal T3 prior to the reduction of thyroid hormone in serum might be taken as an early sign of hippocampus impairment in the progression from SCH to CH.