Major depression and subclinical (grade 2) hypothyroidism

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.

Subclinical thyroid dysfunction and major depressive disorder

PURPOSE

This review attempts to investigate the link between subclinical thyroid dysfunction (SCH) and major depressive disorder (MDD). It has been speculated that SCH may be related to MDD through an autoimmune mechanism.

METHODS

A comprehensive literature search was conducted in the PubMed database for relevant research and review articles.

RESULTS

There appears to be an association between an autoimmune mechanism, possibly involving the thyroid gland, and depressive disorders, but the available evidence is so far inconclusive.

CONCLUSION

Lifetime prevalence of depression is significantly higher in patients with SCH, a finding reflecting a possible effect of SCH in lowering the threshold for the emergence of MDD. The relationship between SCH and MDD is, however, not clear, with large and well-designed studies investigating possible links between reference-range thyroid hormone levels and MDD having as yet found no relation between the two.

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.

Association of Depression and Anxiety Disorders With Autoimmune Thyroiditis: A Systematic Review and Meta-analysis

IMPORTANCE

With a prevalence of 4% to 13% in the United States, autoimmune thyroiditis (AIT) is a major health problem. Besides somatic complications, patients with AIT can also experience psychiatric disorders. The extent of these organic psychiatric diseases in patients with AIT, however, is so far not commonly known.

OBJECTIVE

To provide meta-analytic data on the association of depression and anxiety with AIT.

DATA SOURCES

Google Scholar, the EBSCO Host databases, the Web of Knowledge, and PubMed were searched from inception through December 5, 2017. Articles identified were reviewed and reference lists were searched manually.

STUDY SELECTION

Case-control studies that reported the association between AIT and either depression or anxiety disorders or both were included.

DATA EXTRACTION AND SYNTHESIS

Data extraction was performed by multiple observers following the PRISMA guidelines. Two univariate random-effects meta-analyses were performed, and moderators were tested with Bonferroni-corrected meta-regression analysis. Heterogeneity was assessed with the I2 statistic. Sensitivity analyses tested the robustness of the results. Small study effects were assessed with funnel plots and the Egger test.

MAIN OUTCOMES AND MEASURES

The odds ratio of patients with AIT and depression compared with a healthy control group, as well as the odds ratio of patients with AIT and anxiety disorders compared with a healthy control group.

RESULTS

Nineteen studies comprising 21 independent samples were included, with a total of 36 174 participants (35 168 for depression and 34 094 for anxiety). Patients with AIT, Hashimoto thyroiditis, or subclinical or overt hypothyroidism had significantly higher scores on standardized depression instruments, with an odds ratio of 3.56 (95% CI, 2.14-5.94; I2 = 92.1%). For anxiety disorders, patients with AIT, Hashimoto thyroiditis, or subclinical or overt hypothyroidism had an odds ratio of 2.32 (95% CI, 1.40-3.85; I2 = 89.8%). Funnel plot asymmetry was detected for studies of depression. Study quality assessed with the Newcastle-Ottawa Scale for case-control studies (mean [SD] score: anxiety, 5.77 [1.17]; depression, 5.65 [1.14]; of a possible maximum score of 9) and proportion of females did not modulate the meta-analytic estimate, whereas mean age did.

CONCLUSIONS AND RELEVANCE

This meta-analysis establishes the association between AIT and depression and anxiety disorders. Patients with AIT exhibit an increased chance of developing symptoms of depression and anxiety or of receiving a diagnosis of depression and anxiety disorders. This finding has important implications for patients and could lead to the choice of early treatment-and not only psychotherapeutic treatment-of the organic disorder.

Effect of Mirtazapine on Thyroid Hormones in Adult Patients with Major Depression

Hypothalamic pituitary thyroid (HPT) axis abnormalities and alterations in major depression are reported in literature. The aim of our study was to evaluate the effect of mirtazapine on thyroid hormones after 6 months of therapy in a sample of adult outpatients with Major Depression (MD). 17 adult outpatients (7 men, 10 women) with MD according to DSM-IV criteria, were included in the study. All participants had to have met criteria for a major depressive episode with a score of at least 15 on the Hamilton Depression Rating Scale (HAM-D). Fasting venous blood samples were obtained for determination of serum Thyroid Stimulating Hrmone (TSH), Free T3 (FT3) and Free T4 (FT4) concentrations both at baseline and after 6 months of therapy. HAM-D scores decreased significantly from the first day of treatment to the end of the treatment period (p<0.001) and twelve patients (70.6%) were classified as responders. A significant increase in FT3 concentrations was found between baseline and the end of treatment period (P=0.015) whereas FT4 concentrations decreased (P=0.046). No significant changes were found in TSH levels. Higher FT4 concentrations at baseline predicted higher HAM-D scorers both at baseline and at the end of the treatment period. Furthermore, higher FT3 concentrations at endpoint were found to be predictors of lower HAM-D scores. Long-term treatment with mirtazapine increases FT3 levels and decreases FT4 maybe involving the deiodination process of T4 into T3.

Relationship between thyroid-stimulating hormone levels and risk of depression among the general population with normal free T4 levels

OBJECTIVE

This study assessed the relationship between thyroid-stimulating hormone (TSH) level and risk of depressive symptom in a population with no clinical or laboratory evidence of thyroid dysfunction.

METHODS

This retrospective cohort study included 13,017 subjects (7913 males and 5104 females), 17-84 years of age, who underwent health examinations at the hospital. Subjects had a Beck Depression Inventory (BDI) total score of ≤9 and fell within the normal range of free T4 levels at baseline. The association between gender-specific serum TSH tertile at baseline and the development of clinically significant depressive symptom (i.e., ≥19 BDI total score) on the follow-up visit was evaluated using the Cox proportional hazards model, with adjustment for demographic and life style factors.

RESULTS

The risk of depressive symptom was increased among subjects with the highest tertile TSH level (adjusted hazard ratio [HR], 2.236; 95% confidence interval [CI], 1.443-3.466; p<0.001) as compared with subjects with the lowest tertile in females, but not in males. Even among patients with normal TSH levels, females in the lowest-normal TSH tertile had a higher risk of depressive symptoms (adjusted HR, 2.279; 95% CI, 1.456-3.567; p<0.001) than did those in the highest tertile. The TSH level as a continuous variable significantly predicted the depressive symptoms in females (adjusted HR, 1.402; 95% CI, 1.002-1.812; p=0.027).

CONCLUSIONS

Our finding suggests that suboptimal thyroid function increases vulnerability to the occurrence of depressive symptom and represents a modifiable risk factor for depression in females.

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.

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.

Lack of confirmation of thyroid endophenotype in Bipolar Disorder Type I and their first-degree relatives

BACKGROUND

Among the biological factors associated with the development and outcomes in Bipolar Disorder Type I (BD-I), previous studies have highlighted the involvement of both thyroid function and/or auto-immunity, proposing a thyroid endophenotype. The objective of this study was to determine the presence of thyroid alterations in BD-I and their first-degree relatives (FDR).

METHODOLOGY

Unselected, cross-sectional case-control study with parallel analysis of individuals affected by BD-I (239), their FD-R (131), and 108 healthy controls. Thyroidal functional abnormalities (TSH and free T4) and thyroidal antibodies (thyroglobulin and thyroperoxidase antibodies) were studied. Assessments were carried out in parallel. The sample was described using arithmetic means, standard deviations, percentages and ranges. Chi-square, Student-t tests, ANOVA and Pearson correlation coefficients were used when indicated.

RESULTS

BD-I on actual and/or ever treated with lithium showed significant thyroidal functional abnormalities as compared to their FD-R and healthy controls. This BD-I subgroup showed a significant greater proportion of subjects suffering from subclinical hypothyroidism (22%). The role of gender/lithium interactions was relevant. The groups did not show differences in terms of positivization of thyroidal antibodies.

LIMITATIONS

The crosssectional design and the lack of determination of dietary iodine deficiencies and/or thyroidal ecographical controls may be a drawback.

CONCLUSIONS

The present study supports previous findings on the effect of lithium treatment on thyroidal functional, but did not support previous findings related to a familial association or endophenotype. In addition, the present study did not support a familial aggregation of thyroidal antibodies positivization in pedegrees of BD-I.

Low mood and response to Levothyroxine treatment in Indian patients with subclinical hypothyroidism

BACKGROUND AND AIM

There is considerable controversy regarding the association of subclinical hypothyrodism (SCH) and depression. We studied the association of SCH with low mood and also investigated the effects of L-thyroxine (LT4) therapy on improvement of symptoms.

METHODS

Three hundred patients with SCH and 300 age and sex-matched healthy controls were studied. Serum levels of TSH, FT3, FT4 were measured by chemi-illuminescence. Hamilton Depression Rating Scale (HAM-D) was used to evaluate baseline depression in all participants and subsequently, in 133 patients who had undergone LT4 therapy for 2 months.

RESULTS

The HAM-D scores were significantly higher for cases (10.0±4.7) as compared to controls (2.4±1.5). A positive correlation (r(2)=0.87, p=0.00) was found, between the Hamilton scores and serum TSH levels. No such association was seen between serum FT3, FT4 levels and HAM-D scores. Levothyroxine treatment resulted in a significant decrease in TSH levels and Hamilton scores.

CONCLUSIONS

SCH is associated with low mood and there is a positive correlation between serum TSH levels and HAM-D scores. The administration of Levothyroxine therapy is associated with significant improvement in HAM-D scores. This underlines the importance of thyroid screening in cases of low mood and also asserts the role of Levothyroxine therapy.

Neuropsychiatric manifestations of thyroid disease

The interface between thyroid hormone action and neuropsychiatric function is intricate, and several mechanisms of thyroid hormone uptake into brain tissues, hormone activation, and influences on neurotransmitter generation have been identified. Symptoms of hypothyroidism are nonspecific, whereas those attributed to thyrotoxicosis may be more characteristic. Neuropsychiatric manifestations triggered by thyroid dysfunction likely respond well to reestablishment of the euthyroid state, although some patients have persistent complaints. The addition of LT3 to ongoing LT4 replacement has yet to be definitively shown to be advantageous. Treatment of euthyroid depression with LT3 in addition to antidepressant therapy lacks convincing evidence of superior outcomes.

Subclinical hypothyroidism, mood, and cognition in older adults: a review

OBJECTIVES

To perform a critical review of the literature on the mood and cognitive changes associated with subclinical hypothyroidism (SCH), with an emphasis on older adults. To evaluate these data against the Consensus Statement on the management of SCH from the American Association of Clinical Endocrinologists, the American Thyroid Association, and The Endocrine Society.

METHOD

A comprehensive literature review.

RESULTS

Subclinical hypothyroidism may be associated with an increased risk of mood and cognitive dysfunction, although the strength of this association and the efficacy of replacement hormone therapy require further investigation.

CONCLUSION

It remains unclear whether SCH leads to significant mood and cognitive impairments in most older patients. More research is required to determine the nature and extent of this association and whether thyroid hormone replacement therapy is appropriate and effective in treating SCH-associated neurobehavioral impairments.

Hormone replacement therapy in the geriatric patient: current state of the evidence and questions for the future--estrogen, progesterone, testosterone, and thyroid hormone augmentation in geriatric clinical practice: part 2

The data reviewed herein show that hormone replacement therapies improve some conditions associated with aging. Additionally, some of the long-held fears of significant side effects associated with hormone supplementation may be overstated, especially when providing patients with individualized care and optimal monitoring. We encourage clinicians to consider such interventions based on the evidence presented.More long-term studies are needed to further quantify and substantiate the risks and benefits associated with the use of such therapies.

Thyroid autoimmunity and treatment response to escitalopram in major depression

BACKGROUND

There is evidence that immune alterations play an important part in the pathogenesis of major depression. Thyroid autoimmunity has been found in association with major depression in several studies.

AIM

1) to examine whether the prevalence of anti-thyroid peroxidase autoantibodies (anti-TPO) in depressive patients differs from that in healthy controls; 2) to investigate the possible relationship between thyroid autoimmunity, total T3, free T3, free T4, thyroid-stimulating hormone (TSH), clinical status and treatment outcome in depression.

METHOD

The study group consisted of 129 outpatients (69.8% female; mean age 31.7+/-12.0 years) with major depressive disorder with a Montgomery-Azsberg Depression Rating Scale total score of 22 or higher and 72 healthy controls (62.5% female; mean age 31.7+/-13.1 years). The patients were treated with escitalopram 10-20 mg/day for 12 weeks using open-label placebo non-controlled design. Anti-TPO, total T3, free T3, free T4 and TSH were measured before the treatment.

RESULTS

The anti-TPO was found in eight (8.9%) depressive and two (4.8%) healthy females without statistical difference between these groups. Since anti-TPO was not seen in males, all further statistical analyses were carried out in females. At the end of week 12 of the treatment, 60 female patients (66.7%) were defined as responders and 30 depressive females (33.3%) showed insufficient response to treatment. Although there were no significant differences in the measurements between responders and non-responders, the last group showed a trend for a higher prevalence of anti-TPO compared with responders.

CONCLUSION

Thyroid autoimmunity might be a factor predicting treatment response to antidepressants in depressive patients.

Relationship between TSH levels in the normal range and short-term duloxetine efficacy

BACKGROUND

Whereas studies have suggested an association between abnormal TSH serum levels on antidepressant efficacy in major depressive disorder (MDD), the impact of normal serum TSH levels on antidepressant efficacy is unknown. This study aimed to investigate whether TSH serum levels within the normal range predict short-term antidepressant efficacy.

METHODS

Pooled data from 7 randomized, double-blind, placebo-controlled, MDD clinical trials were analyzed to compare the efficacy of duloxetine depending on baseline serum TSH levels. Adult outpatients with MDD (DSM-IV criteria) received duloxetine (60-120 mg/day, n=1242) or placebo (n=827) for up to 9 weeks. Efficacy was measured based on the 17-item Hamilton Rating Scale for Depression total score change, response rate, remission rate and time to response. TSH serum levels were measured at baseline using Microparticle Enzyme Immunoassay technology. Only patients with a TSH serum level within the normal range were considered for the analysis.

RESULTS

The mean (SD) of baseline TSH serum levels was 1.55 (0.86) mIU/L (median: 1.35; interquartile range: [0.92-1.94]). No significant treatment-by-TSH quartile interaction was evidenced in change from baseline, response, nor remission, indicating that the magnitude of duloxetine's treatment effects did not differ significantly between TSH quartiles. No significant difference in time to response was evidenced between any of the quartiles.

LIMITATIONS

This analysis is a post-hoc analysis of pooled data.

CONCLUSION

In this analysis of pooled data, the overall response to duloxetine in MDD did not differ regarding baseline serum TSH levels when considering TSH within the normal range.

Subclinical hypothyroidism in the elderly

Grade 2,3 and 4 hypothyroidism in the elderly, globally defined as subclinical hypothyroidism, is the object of this minireview. Attention is focused on the prevalence, on the causes and particularly on the clinical features that, in spite of the definition, frequently occur: these are summarized in cognitive impairment, mood disorders, lipid dysmetabolism, cardiovascular abnormalities. Finally a diagnostic algorithm is proposed for the selection of patients to be treated. The authors are of the opinion that a general screening with serum TSH assay for elderly hospitalized patients is worthwhile.

The association of thyroid stimulating hormone levels with cognitive function and depressed mood: the Rancho Bernardo study

OBJECTIVE

To evaluate the association of thyroid stimulating hormone levels with cognitive function and depressed mood in a community-based sample.

DESIGN

Cross-sectional study.

SETTING

Clinic visit in 1999- 2003.

PARTICIPANTS

Community-dwelling men (N=447) and women (N=663) aged 42-99 years.

MEASUREMENT

Cognitive function was assessed with the Buschke-Fuld Selective Reminding Test, the Modified Mini-Mental State Examination, Trails B, and category fluency. Depressed mood was assessed with the Beck Depression Inventory (BDI). A fasting blood sample was obtained for thyroid stimulating hormone (TSH) measurement.

RESULTS

Mean age was 73.6 +/- 10.0 in men and 74.3 +/- 10.4 in women. Mean TSH was 1.9 mu IU/ml in both sexes; 9.0% of men and 24% of women reported thyroid medication use. Mean BDI scores were 4.6 +/- 4.1 in men and 5.2 +/- 4.3 in women; 9% of men and 11% of women used antidepressants. Before and after adjustment for covariates or exclusion of participants taking thyroid hormones, no associations were observed between TSH and cognitive function (ps > 0.10). TSH was inversely associated with BDI (p=0.03) in men, but not women.

CONCLUSIONS

Thyroid stimulating hormone level was unrelated to cognitive function in men and women, and was inversely associated with depressed mood in men only, possibly reflecting the greater use of both thyroid medications and antidepressants by women.

Basal thyrotropin and major depression: relation to clinical variables and treatment outcome

OBJECTIVE

There is a current argument in thyroidology about whether the normal range for basal thyrotropin (TSH) is too broad. Some groups suggest that a TSH of less than 2.5 mIU/L is a better cut-off for euthyroidism. Because major depression is associated with changes in thyroid hormone status and thyroid hormones may be an effective treatment for major depression, we examined whether TSH levels above or below 2.5 mIU/L were related to clinical variables or treatment outcome in euthyroid patients with major depression.

METHODS

Outpatients with major depression (n =166) were assigned to high-normal and low-normal TSH groups based on their basal TSH levels. The 2 groups were compared along clinical variables and treatment outcome.

RESULTS

The low-normal TSH group was significantly more depressed, as measured by Hamilton Depression Rating Scale scores, and had more anxiety symptoms and suicidal tendencies than the high-normal group. There was no difference in treatment response between the groups.

CONCLUSIONS

A comparison of low-normal and high-normal basal TSH groups with major depression revealed significant differences in severity and symptoms of depression but no difference in treatment outcome. These data are preliminary and require replication in a larger sample.

Efficacy and safety of triiodothyronine supplementation in patients with major depressive disorder treated with specific serotonin reuptake inhibitors

The thyroid hormone, triiodothyronine (T3), is used as a supplement to antidepressant treatment of major depression, to accelerate and enhance response and as an augmenter in patients who have not responded. While there is support from controlled trials and meta-analyses for the use of T3 in conjunction with tricyclic antidepressants, the evidence base for supplementation of specific serotonin reuptake inhibitors (SSRIs) with T3 is more limited. We reviewed the available literature on T3 supplementation of SSRIs including open-label studies and randomized controlled trials (RCTs). Five RCTs were identified. Three were enhancement studies in which T3 was administered concurrently with the antidepressant from the start of treatment and two were augmentation studies in which T3 was added to the antidepressant treatment of patients who had not responded. Three open augmentation studies were identified. The RCTs were too disparate in methodology to allow a meta-analysis to be performed. The enhancement studies are inconclusive in that one showed strongly positive effects of T3, one showed no effect and one showed a trend. The open augmentation studies supported an effect of T3 in SSRI non-responsive patients with some support from a large RCT; a smaller, underpowered RCT did not show efficacy. T3 was well tolerated in most of the studies and adverse effects do not seem to be an impediment to clinical use. Some of the studies identified clinical and thyroid function correlates of response that require further investigation. Further research is needed before it can be definitively established whether T3 is an effective supplement to SSRIs in patients with MDD. The appropriate timing of T3 supplementation needs to be explored and also the dose and length of treatment.

Thyroid hormone replacement for subclinical hypothyroidism

BACKGROUND

Subclinical hypothyroidism is defined as an elevated serum thyroid-stimulating hormone (TSH) level with normal free thyroid hormones values. The prevalence of subclinical hypothyroidism is 4% to 8% in the general population, and up to 15% to 18% in women who are over 60 years of age. There is considerable controversy regarding the morbidity, the clinical significance of subclinical hypothyroidism and if these patients should be treated.

OBJECTIVES

To assess the effects of thyroid hormone replacement for subclinical hypothyroidism.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE and LILACS. Ongoing trials databases, reference lists and abstracts of congresses were scrutinized as well.

SELECTION CRITERIA

All studies had to be randomised controlled trials comparing thyroid hormone replacement with placebo or no treatment in adults with subclinical hypothyroidism. Minimum duration of follow-up was one month.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for missing or additional information.

MAIN RESULTS

Twelve trials of six to 14 months duration involving 350 people were included. Eleven trials investigated levothyroxine replacement with placebo, one study compared levothyroxine replacement with no treatment. We did not identify any trial that assessed (cardiovascular) mortality or morbidity. Seven studies evaluated symptoms, mood and quality of life with no statistically significant improvement. One study showed a statistically significant improvement in cognitive function. Six studies assessed serum lipids, there was a trend for reduction in some parameters following levothyroxine replacement. Some echocardiographic parameters improved after levothyroxine replacement therapy, like myocardial relaxation, as indicated by a significant prolongation of the isovolumic relaxation time as well as diastolic dysfunction. Only four studies reported adverse events with no statistically significant differences between groups.

AUTHORS' CONCLUSIONS

In current RCTs, levothyroxine replacement therapy for subclinical hypothyroidism did not result in improved survival or decreased cardiovascular morbidity. Data on health-related quality of life and symptoms did not demonstrate significant differences between intervention groups. Some evidence indicates that levothyroxine replacement improves some parameters of lipid profiles and left ventricular function.

Subclinical hypothyroidism increases the risk for depression in the elderly

In order to determine if subclinical hypothyroidism is a risk factor for depression in the elderly, a total of 323 individuals over 60 years old were interviewed using the Structured Clinical Interview for Diagnosis and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) for mood disturbances. Patients were divided into Group I: 252 patients (184 females, 68 males; median age: 67 years, range: 60-89 years) with elevated serum thyrotropin (TSH) levels and Group II: 71 patients (45 females, 26 males; median age: 67 years, range: 60-92 years) with diagnosis of depression. Serum TSH and free thyroxine (fT4) were measured by sensitive assays. Thyroid antibodies were determined by IRMA. Depression was observed in 24 (9.5%) Group I patients and was frequent in subclinical hypothyroidism patients (14/24 = 58.3%). On the other hand, elevated TSH levels were found in 22 (30.9%) Group II patients. Depression was observed more frequently among individuals with subclinical (74/149 = 49.7%) hypothyroidism than among individuals with overt hypothyroidism (21/125 = 16.8%) (p < 0.001). Indeed, subclinical hypothyroidism increased the risk for a patient to present depression more than four times (OR = 4.886; 95% confidence interval = 2.768-8.627). Our results demonstrate that subclinical hypothyroidism increases the risk for depression and emphasize the importance of thyroid screening tests in the elderly.

Elevated thyroid indices in children and adolescents with obsessive-compulsive disorder: effects of clomipramine treatment

OBJECTIVE

To examine the basal thyroid function in pediatric Obsessive Compulsive Disorder (OCD) versus controls, and to explore the relation between baseline thyroid measures and response to clomipramine treatment, and the effects of treatment on thyroid hormones.

METHODS

Sixteen children and adolescents with DSM-III-R OCE and 13 control children and adolescents without psychiatric illness were compared on basal measures of thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). For the OCD subjects, samples were compared pre- and post- 4 weeks of treatment with clomipramine. Response of OCD symptoms was measured by the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS).

RESULTS

OCD subjects demonstrated subtle but significant elevations of TSH, T3, and T4 pre-treatment compared to controls. Clomipramine treatment was associated with significant decreases in TSH and T3 concentrations. Pre-treatment TSH and T4 concentrations correlated with reductions in CY-BOCS following 8 weeks of clomipramine.

CONCLUSION

Elevated thyroid function at baseline may be a biomarker of OCD improvement, and may reflect aspects of the underlying pathophysiology of OCD.

Low yield of thyroid-stimulating hormone testing in elderly patients with depression

Although hypothyroidism is purportedly an important cause of depression, prior studies have involved small samples of young people and produced conflicting results. We examined the yield of thyroid-stimulating hormone (TSH) testing in a large group of elderly patients with major depression or dysthymic disorder. The study sample comprised 883 outpatients aged 60 years or older from 18 primary care sites enrolled in the intervention arm of a clinical trial of depression management. Thyroid function was assessed by a single TSH value. Depressive diagnoses were confirmed with the Structured Clinical Interview for DSM-IV (SCID) and depression severity was assessed with the HSCL-20, a modified depression scale of the Hopkins Symptom Checklist. TSH results were available for 725 (82.1%) participants. Although 32 (4.4%) of those tested had TSH>5 mIU/L, the vast majority (27/32) had marginally elevated results (5.1-9.4 mIU/L). Only five patients (0.7%) had TSH levels >10 mIU/L. Patients with elevated TSH did not differ from those with TSH < or = 5 mIU/L in the severity or symptom pattern of depression as measured by the baseline HSCL-20 score (P=.37) or SCID score (P=.44). These findings should caution physicians against acceptance of borderline TSH values as the primary cause of a patient's clinical depression.

Disfunções mínimas da tiróide: hipotiroidismo subclínico e hipertiroidismo subclínico

Hipotiroidismo subclínico (SHT) e hipertiroidismo subclínico (SCH) são definidos pelas concentrações normais de T4 e T3 livres séricos associadas com valores de TSH elevado (SHT) ou suprimido (SCH). As prevalências são baixas e sintomas e sinais de disfunção tiroideana escassos. No SHT, colesterol total e LDL-C estão ligeiramente elevados, e tratamento com levotiroxina pode influir nos valores dos lipídeos. Ocorre diminuição da contratilidade do miocárdio e aumento da resistência vascular periférica, que melhoram com o tratamento. Fibrilação atrial é mais freqüente no SCH, e há aumento do índice de massa do ventrículo esquerdo, da contratilidade cardíaca, disfunção diastólica e indução de batimentos atriais ectópicos que regridem com uso de beta-bloqueadores. No SCH, ocorre diminuição da densidade óssea. Depressão, doença do pânico e alterações de testes cognitivos são freqüentes no SHT. O tratamento do SHT é indicado com TSH sérico maior do que 8mU/L e presença de anticorpos antitiroideanos, e do SCH endógeno, quando existem sintomas, em idosos ou concentração de TSH menor do que 0,1mU/L.

Adjunctive oxcarbazepine in comorbid anxiety and affective disorder with hyponatremic seizure: case analysis and literature review

Rational polypharmacy is required for management of refractory psychiatric disorders. Antiepileptic drugs are increasingly used as primary or adjunctive agents in the treatment of affective, schizoaffective, anxiety, and impulse control disorders. In this case report, the authors present the first case of hyponatremic seizure associated with oxcarbazepine in adjunctive treatment of comorbid affective/anxiety disorders.

Hypothyroidism Presenting as Psychosis: Myxedema Madness Revisited

Hypothyroidism is a medical condition commonly encountered in a variety of clinical settings. The clinical presentations of thyroid hormone deficiency are diverse, complicated, and often overlooked. Hypothyroidism is a potential etiology for multiple somatic complaints and a variety of psychological disturbances. The physical complaints are primarily related to metabolic slowing secondary to lack of thyroid hormone. Psychiatric presentations include cognitive dysfunction, affective disorders, and psychosis. The realization that hypothyroidism might be the potential etiology of an assortment of symptoms is critical in the identification and treatment of the hypothyroid patient. Once hypothyroidism is identified, symptoms usually respond to appropriate thyroid hormone supplementation. This article presents a case of clinical hypothyroidism that came to clinical attention due to psychotic symptoms consisting of auditory and visual hallucinations. The case is followed by a brief discussion of the literature describing the relationship of hypothyroidism and psychiatric symptomatology. References were identified with an English language-based MEDLINE search (1966-2003) using the terms thyroid, hypothyroid, depression, dementia, delirium, mania, bipolar disorder, psychosis, and myxedema and utilization of referenced articles.

Thyroid indices and response to fluoxetine and nortriptyline in major depression

We investigated: (i) the status of thyroid hormones and their clinical correlates in patients with major depression; (ii) changes in thyroid hormone status after treatment with fluoxetine versus nortriptyline; and (iii) whether blunted thyrotropin-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH) challenge predicts improvement after 6 weeks of fluoxetine versus nortriptyline treatment. Patients with major depression entering a treatment trial were assessed with the Structured Clinical Interview for DSM-III-R and were rated on the Montgomery-Asberg Depression Rating Scale (MADRS). Blood samples were taken for TSH, thyroxine (T4) and free thyroxine (FT4) measurement, and the maximum TSH response (deltamaxTSH) to a TRH challenge test was undertaken. Patients were then randomly assigned to receive fluoxetine or nortriptyline for six weeks. At 6 weeks, patients repeated the thyroid hormone assessment and completed the MADRS. Mean concentrations of TSH, T4, FT4 and deltamaxTSH were within reference ranges. T4 and FT4 levels decreased significantly after treatment in responders, but not in nonresponders. After treatment, deltamaxTSH concentrations decreased significantly in patients who responded to fluoxetine, and increased in patients who responded to nortriptyline. Patients with deltamaxTSH blunting at pretreatment were more likely to be male, to have higher MADRS scores and have a history of alcohol and drug dependence. Patients with a pretreatment deltamaxTSH of < 3.0 microm/ml showed greater improvement on the MADRS when treated with fluoxetine than if treated with nortriptyline. We observed a decrease in T4 and FT4 in responders to treatment with fluoxetine or nortriptyline. Positive relationships between deltamaxTSH blunting and alcohol and drug abuse and severity of depression were found. Patients with blunted deltamaxTSH responded better to fluoxetine than to nortriptyline. It is suggested that a blunted DmaxTSH may reflect a predominantly serotonergic disturbance in this group of patients with major depression.

Cognitive and neuropsychiatric aspects of subclinical hypothyroidism: significance in the elderly

The effects of overt hypothyroidism (HO) on cognition and mood are well established, and HO is considered a common cause of reversible dementia. There is now increasing evidence to suggest that subclinical hypothyroidism (ie, elevated thyroid stimulating hormone in the presence of normal thyroxine concentrations) may be a predisposing factor for depression, cognitive impairment, and dementia. Subclinical hypothyroidism is more common than HO and is most prevalent in the elderly, particularly in women. Older adults may be more vulnerable to the effects of subclinical hypothyroidism, given age-related changes to the hypothalamic-pituitary-thyroid axis, and there is an association between thyroid status and cognitive decline and dementia in the elderly. The purpose of this review is to summarize existing data on the cognitive and neuropsychiatric consequences of subclinical hypothyroidism, benefits of treatment, and recommendations for screening and monitoring in older adults.

Thyroid indices and treatment outcome in bulimia nervosa

OBJECTIVE

This study examined the thyroxine (T4) and free T4 (FT4) status of women with bulimia nervosa and its value as a predictor of outcome.

METHOD

A total of 135 women with bulimia nervosa underwent 12-weeks cognitive behavioral therapy treatment. Prior to and at 3-year follow-up patients completed psychiatric assessments and serumT4 and FT4 were measured.

RESULTS

At 3-year follow-up, 71% had no eating disorder and 29% met criteria for any eating disorder diagnosis. Mean T4 and FT4 concentrations were within normal ranges. Pre-treatment T4 and FT4 concentrations were inversely associated with food restriction and purging frequency, respectively. Compared with women with no eating disorder, those with any eating disorder at follow-up had lower pretreatment T4 concentrations. When pre-treatment food restriction, oral contraceptive use and binge frequency where controlled for, low T4 concentration was the only predictor of eating disorder diagnosis at follow-up.

CONCLUSION

Low T4 concentrations at pretreatment may be a predictor of poor outcome in bulimia nervosa.

High serum TSH levels are associated with depression in the elderly

In order to investigate the association between elevated serum TSH levels and depression in the elderly, we conducted a population-based study of 451 over 60-year-old outpatients of a general University Hospital. Patients were divided into Group I (GI) (248 individuals) with high serum TSH levels, but otherwise no important condition or disease, and Group II (GII) (203 patients) with no previous diagnosis of thyroid or mood disease, referred to the hospital because of nonthyroidal severe diseases. All patients were clinically examined and classified according to DMS-IV for mood disturbance and had serum TSH, free T4 levels and antithyroid antibodies measured. High serum TSH levels (11.6+/-14.8 mU/l) were observed in 65/203 (32%) patients of GII. Among these patients, 42/65 (65%) had normal free T4 concentrations (1.23+/-0.98 ng/dl), no clinical manifestation of hypothyroidism and thus were considered to present subclinical hypothyroidism. Depression was observed in 24 cases from GI (9.7%) and 29 from GII (14.3%) and was frequent in the subclinical hypothyroid patients (49%). Our results suggest that mood disturbances are frequent in the elderly with elevated serum TSH levels, but they do not differ in the primary hypothyroid and the nonthyroidal sick patients.

T3 blood levels and treatment outcome in depression

OBJECTIVE

We examined the correlation between the basal triiodothyronine resin uptake (T3-RU) levels in depressed subjects and the response to anti-depressant treatment.

METHOD

We treated with fluoxetine 235 outpatients meeting DSM-IV criteria for major depression. We measured T3 resin uptake (T3-RU) levels before the onset of treatment. The 17-item Hamilton Rating Scale for Depression (Ham-D-17) was administered before, during and after the eight weeks of treatment to assess changes in depressive symptoms.

RESULTS

16 patients (6.8 percent) had low T3-RU levels (range 16.5-21), and 7 patients (3.0 percent) had high T3-RU levels (range 36-38). No relationship was found between T3-RU levels and clinical improvement, defined as either total Ham-D-17 score change or Ham-D-17 score < or = 7 in the last 3 weeks of treatment, even after adjusting for baseline severity of depression.

CONCLUSION

Abnormal T3-RU levels are rather uncommon in outpatient depression and do not correlate with the response to antidepressant treatment or lack thereof.

The effect of L-tryptophan on conditioned reflex learning and behavior in rats with experimental pathology of the thyroid gland

The effects of L-tryptophan on conditioned reflex learning and behavior were studied in male rats with deficient and excess thyroid hormones levels. The learning process was studied using a model consisting of a conditioned active avoidance response; animal behavior was assessed in an open field test. These studies showed that in conditions of thyroid hormone deficiency. L-tryptophan had positive effects on the acquisition and reproduction of the active avoidance reflex, restoring the ability of the animals to learn actively; L-tryptophan increased investigative activity in the open field test. In conditions of increased thyroid hormone levels, L-tryptophan reversed the mild stimulating effects of thyroid hormones on the processes of developing and performing the active avoidance habit, and increased investigative activity, but decreased the amount of grooming.

Management practices among primary care physicians and thyroid specialists in the care of hypothyroid patients

Prospective studies are not available to address various issues commonly encountered in the management of hypothyroid patients. We have conducted a case-based mail survey of American Thyroid Association (ATA) members and primary care providers (PCP) regarding hypothyroidism management issues. A majority of ATA members and a minority of PCPs used antithyroid antibody testing in the evaluation of hypothyroidism. Approximately 2/3 of all respondents indicated that they would treat patients with mild thyroid failure when antithyroid antibodies are negative; 77% of PCPs and 95% of ATA members recommended treatment when antibodies are positive. For a young patient with mild thyroid failure, 71% of ATA members would initiate a full levothyroxine (LT4) replacement dose of 1.6 microg/kg per day or slightly lower; PCPs were more likely to start with a low dose and titrate upwards. For a young patient with overt hypothyroidism, 42% of PCPs and 51% of ATA respondents recommended an initial full LT4 replacement dose. The majority of all respondents would start with a low LT4 dose and adjust the dose gradually in an elderly patient, regardless of the severity of thyroid hormone deficiency. More than 40% of ATA respondents chose a target thyrotropin (TSH) range of 0.5-2.0 microU/mL for a young patient while 39% favored a goal of 1.0-4.0 microU/mL for an elderly patient. PCPs more often chose a broader TSH goal of 0.5-5.0 microU/mL. In conclusion, the current practice patterns of PCPs and ATA members that were elicited in this survey differ significantly in regard to the evaluation and management of hypothyroidism.

Treatment-resistant depression

Our ability to treat depression has improved with the availability of receptor-specific and chemically diverse groups of antidepressants. Even now, most of the short-term studies indicate that about 20% of depressed patients remain resistant to treatment. Therefore, it is important to properly assess the treatment-resistant depressed (TRD) patients and to separate the truly refractory patients from those inadequately treated. Undiagnosed medical conditions should be eliminated. TRD is neither a clinically nor a biologically identifiable entity. As there are no established methods for the treatment of TRD, all options should be considered. The clinician can be enriched by the knowledge of the treatment modalities available, and yet, in treating an individual patient, clinical skills, intuitive judgment, family history of response to drugs and side effects, all play a vital role. Several of the approaches described in the paper indicate available methods and their merits in general but there is no way of ascertaining by which particular method a patient should be treated. The three common methods of treatment are substitution of one antidepressant drug for another, combination therapies and augmentation techniques. These are based on clinical experiences and not research findings. Therefore the treatment of TRD patients is more an art than a science. The physician should assess all the psychopathological, phenomenological and psychosocial variables to appropriately treat an individual patient.

Hypothyroidism and depression: a therapeutic challenge

OBJECTIVE

To describe a patient with longstanding depression and hypothyroidism who had marked mood improvement only after triiodothyronine (T3) was added to her thyroxine (T4) replacement therapy.

CASE SUMMARY

A 50-year-old white woman had a long history of depression and documented hypothyroidism since 1991. Despite treatment with T4 with dosages up to 0.3 mg/d, she continued to be depressed, have symptoms of hypothyroidism, and have a persistently elevated thyroid-stimulating hormone concentration. Addition of a low dose of T3 to her regimen resulted in significant mood improvement.

DISCUSSION

The relationship between hypothyroidism and depression is well known. It is possible that this patient's long history of depression may have been a consequence of inadequately treated hypothyroidism, due either to poor patient compliance or resistance to T4. Nevertheless, her depression responded to addition of a low dose of T3 to her regimen. This case emphasizes the importance of screening depressed patients for hypothyroidism. Her clinical course also suggests that depression related to hypothyroidism may be more responsive to a regimen that includes T3 rather than to replacement with T4 alone. This is consistent with the observation that T3 is superior to T4 as adjuvant therapy in the treatment of unipolar depression.

CONCLUSIONS

Depressed patients should be screened for hypothyroidism. In hypothyroid patients, depression may be more responsive to a replacement regimen that includes T3 rather than T4 alone. Therefore, inclusion of T3 in the treatment regimen may be warranted after adequate trial with T4 alone.

Disclosing subclinical thyroid disease. An approach to mild laboratory abnormalities and vague or absent symptoms

Patients with subclinical thyroid disease often have no apparent symptoms or only nonspecific complaints. However, increasing evidence that early disease is associated with behavioral, psychiatric, biochemical, and organ-specific abnormalities has led several specialty organizations to publish or modify position papers. Serum TSH testing is the most sensitive method of identifying early thyroid dysfunction. It should be considered in patients who have risk factors for mild thyroid failure, have symptoms that could be related to thyroid disease, or are taking exogenous thyroid hormone. T4 therapy should be strongly considered in patients with a TSH level of 10 mIU/L or more. If observation is elected in asymptomatic patients with lesser TSH elevation, periodic measurements are advised. In patients with TSH suppression who are taking thyroid hormone, the dose should be lowered. If the TSH level is decreased because of endogenous suppression and free-T4 and T3 levels are normal, options include observation and treatment with an antithyroid drug or thyroid ablation. Early therapy should be considered in older patients and those with heart disease or nodular thyroid disease. The goal of all treatment methods should be to keep the TSH level in the normal range.

Association between lower serum free T4 and greater mood instability and depression in lithium-maintained bipolar patients

OBJECTIVE

This investigation evaluated the relationship between changes in thyroid indices and mood stability during lithium and carbamazepine prophylaxis for bipolar disorder.

METHOD

In the first 2 years, 30 patients with bipolar mood disorder were randomly assigned to 1 year of lithium and then 1 year of carbamazepine, or vice versa; in the third year, they received lithium plus carbamazepine. By stepwise regression analysis, the degree and timing of lithium- and carbamazepine-induced thyroid changes and their subsequent relationship to long-term mood stability were evaluated.

RESULTS

During the lithium phase, there was a significant inverse relationship between morbidity and mean serum level of free T4, i.e., a lower mean serum level of free T4 was associated with more affective episodes and greater severity of depression as shown by the Beck Depression Inventory. During the carbamazepine phase, there was an inverse relationship between mean level of total T4 and global severity rating. During the combination phase, no relationships between thyroid indices and clinical outcome were significant.

CONCLUSIONS

In the lithium phase, a low level of free T4 was associated with more affective episodes and greater severity of depression. Whether this mood instability is causally related to low free T4 levels and whether it can be attenuated with T4 replacement remain to be studied in a controlled setting.

Low levels of transthyretin in the CSF of depressed patients

OBJECTIVE

Transthyretin plays an important role in the transport and distribution of thyroid hormone in the central nervous system (CNS). This study replicated and extended to patients with nonrefractory depressive illness a pilot study indicating that patients with refractory major depression have significantly lower levels of CSF transthyretin than do healthy comparison subjects.

METHOD

Lumbar punctures were performed in drug-free subjects with DSM-III-R major depression (N = 18), DSM-III-R bipolar disorder, depressed phase (N = 1), and healthy comparison subjects (N = 24). CSF concentrations of transthyretin, determined by a quantitative dot-immunobinding assay, of the depressed patients and comparison subjects were compared by analysis of covariance (ANCOVA). The relationship between CSF transthyretin levels and Hamilton Depression Rating Scale scores was determined in a subset of the depressed patients.

RESULTS

CSF concentrations of transthyretin were significantly lower in the depressed patients than in the comparison subjects by ANCOVA. Within the depressed group there was no significant overall correlation between CSF transthyretin levels and Hamilton depression scale scores, but there was a significant inverse correlation in male depressed patients (N = 8) between CSF transthyretin concentrations and Hamilton depression scores.

CONCLUSIONS

Lower CSF transthyretin concentrations in depressed patients may reflect either a stable trait in this population or a state change secondary to depression or other factors. Lower CSF transthyretin concentrations may result in altered CNS thyroid hormone homeostasis. Such alteration could account for certain mood and neurovegetative symptoms of depression and might contribute to failure of standard antidepressant treatment.

Peripheral thyroid hormone levels in treatment resistant depression

BACKGROUND

Various abnormalities of thyroid function have been inconsistently reported in major depression. The inconsistency between studies may be due to several factors including the stage of treatment resistance.

METHODS

One hundred and one patients with major depressive disorder receiving their first antidepressant for their current major depressant episode had baseline thyroid function test performed. On completion of treatment, their stage of antidepressant resistance was determined.

RESULTS

Severity of depression but not any peripheral thyroid hormone level was associated with stage of anti-depressant treatment resistance.

CONCLUSIONS

Stage of treatment resistance does not appear to be a factor in the variability in peripheral thyroid hormone levels in unipolar major depression.

Management of the unexpected result: compensated hypothyroidism

The combination of elevated serum thyrotropin and normal serum thyroxine is called compensated or subclinical hypothyroidism. This most commonly represents clinically silent autoimmune thyroiditis. Whether this condition warrants treatment or simply observation is still debated. The risk of developing overt hypothyroidism is high in females with elevated thyrotropin above 10 mU/l and/or positive thyroid microsomal antibodies. Males are also at high risk of progression towards overt hypothyroidism, regardless of antibody status or degree of thyrotropin elevation. We advise routine treatment of only those at high risk of developing overt hypothyroidism.

Certainty, leaps of faith, and tradition: rethinking clinical interventions

Clinical decision making requires that clinicians think quickly and in ways that will foster optimal, safe client care. Tradition influences clinical decision making, enhancing efficiency of resulting nursing action; however, since many decisions must be based on data that are either uncertain, incomplete, or indirect, clinicians are readily ensnared in processes involving potentially faulty logic associated with tradition. The author addresses the tenacity of tradition and then focuses on three processes--consensus formation, the grounding of certainty in inductive reasoning, and affirming the consequent--that have affected clinical decision making. For some recipients of care, tradition has had a substantial and invalid influence on their ability to access care.

Stapedial reflex: a biological index found to be abnormal in clinical and subclinical hypothyroidism

There is only limited evidence for biological parameter abnormalities in subclinical hypothyroidism. The aim of this study was to investigate the impact of varying degrees of thyroid failure on the stapedial reflex as a biological index, and establish its role in the evaluation of the hypothyroid patient. We studied 10 patients with subclinical hypothyroidism, 10 patients with clinical hypothyroidism, and 20 controls. All three parameters of stapedial reflex (amplitude, decay, and threshold) were measured before and after restoration of euthyroidism through thyroxine administration. Data are given as mean +/- SEM. Stapedial reflex maximal amplitudes were different among the groups studied (p < 0.0001), as values in subclinical (4.3 +/- 0.4 mm) and clinical (3.7 +/- 0.3 mm) groups before treatment were lower (p < 0.05) than those of control (5.7 +/- 0.3 mm), and subclinical (6.4 +/- 0.5 mm) and clinical (5.6 +/- 0.4 mm) groups after treatment. Similarly, stapedial reflex decays were different among the groups studied (p < 0.001), as values in subclinical (81 +/- 7 ms) and clinical (89 +/- 4 ms) groups before treatment were higher (p < 0.05) than those in control (65 +/- 2 ms), subclinical (56 +/- 8 ms), and clinical (61 +/- 8 mm) groups after treatment. There was no significant difference among the groups for stapedial reflex threshold or significant correlation between stapedial reflex parameters and thyroid function tests. Stapedial reflex, a biological parameter that reflects neuromuscular status, is abnormal in patients with subclinical and clinical hypothyroidism and returns to normal when clinical and biochemical euthyroidism has been achieved through thyroxine administration.

Psychoneuroendocrinology of mood disorders. The hypothalamic-pituitary-thyroid axis

Abnormal thyroid functioning can affect mood and influence the course of unipolar and bipolar disorder. Even mild thyroid dysfunction has been associated with changes in mood and cognitive functioning. Thyroid hormone supplementation may have role in the treatment of certain mood disorders, particularly rapid-cycling bipolar disorder. Women are more vulnerable to thyroid dysfunction than men and also respond better to thyroid augmentation. This article reviews the relationship between thyroid function and mood, and the use of thyroid hormones in the treatment of mood disorders. The impact of gender on these issues is also discussed.

Psychopathological and cognitive features in subclinical hypothyroidism

1. To evaluate effective and cognitive dysfunctions in subjects with a marginal form of thyroid hypofunction the authors studied a population of female goiter patients, divided in two groups on the basis of thyroid function: euthyroidism and subclinical hypothyroidism (SCH). 2. The SCH patients were treated with levothyroxine (LT4) in order to obtain euthyroidism, as demonstrated by normalization of the hormonal pattern. 3. Both groups were evaluated with a wide range of psychometric tests (Wechsler memory test, scribble test, reaction times) and psychopathological rating scales (Hamilton rating scales for depression and anxiety, brief psychiatric rating scale) at admission and after 3 months. 4. At admission, a significant decrease in logical memory was found in SCH patients; no differences in affectivity ratings were found between the groups. 5. After LT4 treatment, SCH patients showed a significant improvement in some items of memory performance. 6. In conclusion, when interfering factors relating to the perception of disease were excluded by employing euthyroid goiter patients as a comparison group, SCH appeared associated only with memory impairment, while the impairment of affective functions described in previous studies comparing SCH patients with normal controls was not confirmed. A significant improvement of memory skills was induced by LT4 treatment in SCH patients.

Hypothalamic-pituitary-thyroid-axis function in treatment resistant depression

Recently, there were some reports that the prevalence of various grades of hypothyroidism may be increased in patients with treatment resistant depression (TRD). The aim of the present study was to examine serum basal thyroid-stimulating hormone (TSH) and thyroxine (T4) levels in 36 major depressed subjects, of whom 27 had TRD and 15 were normal volunteers. There were no significant differences in serum basal TSH or T4 levels between major depressed subjects and normal controls, or between patients with TRD versus normal controls or subjects without TRD. There was a trend towards lower serum basal T4 concentrations in patients with TRD than in other depressed patients and normal controls. One patient with TRD had basal serum TSH levels in the hyperthyroid range. Two subjects, one with TRD and one normal control, had serum TSH values in the subclinical hypothyroid zone, but their serum T4 values were in the euthyroid range. There were no significant relationships between basal TSH or T4 and severity of illness, staging of depression based on prior treatment non-response, length of the depressive episode, duration of illness, or number of previous depressive episodes. In conclusion, the results of this study do not provide evidence that (subclinical) hypothyroidism occurs more than coincidentally in depressed patients with TRD.