Thyroid hypofunction in patients with rapid-cycling bipolar disorder after lithium challenge

Prevalence and outcomes of rapid cycling bipolar disorder: Mixed method systematic meta-review

Rapid-cycling in bipolar disorder (RC-BD) is associated with greater illness morbidity and inferior treatment response but many aspects remain unclear, prompting this systematic review of its definitions, prevalence, and clinical characteristics. We searched multiple literature databases through April 2022 for systematic reviews or meta-analyses on RC-BD and extracted associated definitions, prevalence, risk-factors, and clinical outcomes. We assessed study quality (NIH Quality Assessment Tool) and levels of evidence (Oxford criteria). Of 146 identified reviews, 22 fulfilling selection criteria were included, yielding 30 studies involving 13,698 BD patients, of whom 3777 (27.6% [CI: 26.8-28.3]) were considered RC-BD, as defined in 14 reports by ≥4 recurrences/year within the past 12 months or in any year, without considering responsiveness to treatment. Random-effects meta-analytically pooled one-year prevalence was 22.3% [CI: 14.4-32.9] in 12 reports and lifetime prevalence was 35.5% [27.6-44.3] in 18 heterogenous reports. Meta-regression indicated greater lifetime prevalence of RC-BD among women than men (p=0.003). Association of RC-BD with suicide attempts, and unsatisfactory response to mood-stabilizers was supported by strong evidence (Level 1); associations with childhood maltreatment, mixed-features, female sex, and type-II BD had moderate evidence (Level 2). Other factors: genetic predisposition, metabolic disturbances or hypothyroidism, antidepressant exposure, predominant depressive polarity (Level 3), along with greater illness duration and immune-inflammatory dysfunction (Level 4) require further study. RC-BD was consistently recognized as having high prevalence (22.3%-35.5% of BD cases) and inferior treatment response. Identified associated factors can inform clinical practice. Long-term illness-course, metabolic factors, and optimal treatment require further investigation.

Complexities of cooccurrence of catatonia and autoimmune thyroiditis in bipolar disorder: A case series and selective review

In recent years the neurobiological underpinnings of catatonia have been an emerging area of interest. Catatonia is frequently encountered in mood disorders, neurological disorders and systemic illnesses. Furthermore, the manifestation of catatonia in autoimmune disorders such as NMDA receptor antibody encephalitis and thyroiditis reinforces its neuropsychiatric nature. Irrespective of cause benzodiazepines and electroconvulsive therapy remain the standard treatments for catatonia, although a proportion fail to respond to the same. This report describes three women with pre-existing bipolar disorder presenting in catatonia. Interestingly in all three, while benzodiazepines and electroconvulsive therapy failed, a dramatic resolution of catatonia with corticosteroids was noted following the detection of Hashimoto's thyroiditis. Hashimoto's encephalopathy presenting as catatonia has been reported, but our patients' profile differed in having had an a priory diagnosis of bipolar disorder. Given that both catatonia and thyroid dysfunction are frequently encountered in bipolar disorder, Hashimoto's encephalopathy as a potential cause for this concurrent manifestation in bipolar disorder may be overlooked. Therefore, it is essential to suspect Hashimoto's encephalopathy when catatonia manifests in bipolar disorder. A timely evaluation would be prudent as they may fail to respond to standard treatments for catatonia but respond remarkably to corticosteroids, saving much time and angst. Recent evidence implicates immune system dysfunction, with neuroinflammation and peripheral immune dysregulation contributing to the pathophysiology of bipolar disorder as well as catatonia. Findings from this study reaffirm the role of immune system dysfunction common to the etiopathogenesis of all these disorders, highlighting the complex interplay between catatonia, thyroiditis and bipolar disorder.

Role of thyroid hormone therapy in depressive disorders

PURPOSE

The close association among thyroid metabolism, mood disorders and behavior has long been known. The old and modern uses of thyroid hormones to modulate the expression of depression and bipolar disorder and to improve clinical outcome when used in conjunction with psychotropic medications.

METHODS

A literature search was performed to identify studies investigating the effects of thyroid hormone treatment in patient s with mood disorders.

RESULTS

The successful modification of mood disorders with thyroid hormone underscores the association between endocrine and cerebral systems in these disorders. Thyroid hormones have a profound influence on behavior and appear to be capable of modulating the phenotypic expression of major mood disorders. In fact, there is evidence that triiodothyronine (LT3) may accelerate the antidepressant response to antidepressants, and studies suggest that LT3 also may augment the response to antidepressants in refractory depression. Add-on treatment with supraphysiologic doses of levothyroxine (LT4) has shown efficacy in open-label and in placebo-controlled studies, including in rapid cycling and prophylaxis-resistant bipolar disorder, and with acute refractory uni- or bipolar depression. Functional brain-imaging studies (PET) demonstrated that administration of supraphysiologic LT4 improves depressive symptoms in patients with bipolar depression by modulating cerebral activity in the anterior limbic network.

CONCLUSION

The add-on administration of supraphysiologic doses of LT4 is a promising strategy in patients with refractory bipolar and depressive mood disorders.

Rapid cycling bipolar disorder is associated with antithyroid antibodies, instead of thyroid dysfunction

BACKGROUND

Conclusions regarding the association between antithyroid antibodies or thyroid dysfunction and rapid cycling bipolar disorder (RCBD) have been conflicting. Previous studies suggest that the impact of antithyroid antibodies on mental wellbeing seems to be independent of thyroid function. Here, we investigated their independent association with RCBD in a large, well-defined population of bipolar disorder (BD).

METHODS

Fast serum levels of free thyroxine (FT4), free triiodothyronine (FT3), thyroid Stimulating Hormone (TSH), TPO-abs and Tg-abs were simultaneously measured in 352 patients with BD. Clinical features of BD were collected through semi-structural interview conducted by trained interviewers with background of psychiatric education.

RESULTS

Neither hypothyroidism nor hyperthyroidism was significantly associated with RCBD. Both TPO-abs and Tg-abs were significantly related to RCBD, even after controlling for gender, age, marriage status, education, antidepressants treatment, comorbidity of thyroid diseases, and thyroid function (serum levels of FT3, FT4 and TSH). Although TPO-abs and Tg-abs were highly correlated with each other, binary logistic regression with forward LR selected TPO-abs, instead of Tg-abs, to be associated with RCBD. TPO-abs was significantly, independently of Tg-abs, associated with hyperthyroidism, while Tg-abs was marginally significantly related to hypothyroidism at the presence of TPO-abs.

CONCLUSION

TPO-abs might be treated as a biomarker of RCBD. Further exploring the underlying mechanism might help understand the nature of RCBD and find out new treatment target for it.

Adjunctive thyroid hormone treatment in rapid cycling bipolar disorder: A double-blind placebo-controlled trial of levothyroxine (L-T4 ) and triiodothyronine (T3 )

OBJECTIVES

This report describes the first comparative double-blind, placebo-controlled trial of levothyroxine (L-T₄ ) and triiodothyronine (T₃ ) as adjunctive treatments in rapid cycling bipolar disorder.

METHODS

Thirty-two treatment-resistant, rapid cycling patients who had failed a trial of lithium were randomized into three treatment arms: L-T₄ , T₃ , or placebo. They were followed for ≥4 months with weekly clinical and endocrine assessments.

RESULTS

There were no statistically significant differences between the groups in age, gender, duration of illness, or thyroid status. Markov chain analyses were employed to assess treatment effects on cycling patterns among mood states (euthymia, depression, mania, and mixed). Within groups, post-treatment the L-T₄ group spent significantly less time depressed or in a mixed state and greater time euthymic. The T₃ and placebo groups did not differ significantly pre- and post-treatment in any mood state, although the pattern of effects was the same for the T₃ group as for the L-T₄ group. Between groups, the L-T₄ group had a significantly greater increase in time euthymic and decrease in time in the mixed state than the placebo group. Other group differences were not significant, although they were in the expected direction.

CONCLUSIONS

The findings in this first double-blind study directly comparing the effects of L-T₄ and T₃ therapy against placebo provide evidence for the benefit of adjunctive L-T₄ in alleviating resistant depression, reducing time in mixed states and increasing time euthymic. Adjunctive T₃ did not show statistically significant evidence of benefit over placebo in reducing the time spent in disturbed mood states.

Comparative approaches to understanding thyroid hormone regulation of neurogenesis

Thyroid hormone (TH) signalling, an evolutionary conserved pathway, is crucial for brain function and cognition throughout life, from early development to ageing. In humans, TH deficiency during pregnancy alters offspring brain development, increasing the risk of cognitive disorders. How TH regulates neurogenesis and subsequent behaviour and cognitive functions remains a major research challenge. Cellular and molecular mechanisms underlying TH signalling on proliferation, survival, determination, migration, differentiation and maturation have been studied in mammalian animal models for over a century. However, recent data show that THs also influence embryonic and adult neurogenesis throughout vertebrates (from mammals to teleosts). These latest observations raise the question of how TH availability is controlled during neurogenesis and particularly in specific neural stem cell populations. This review deals with the role of TH in regulating neurogenesis in the developing and the adult brain across different vertebrate species. Such evo-devo approaches can shed new light on (i) the evolution of the nervous system and (ii) the evolutionary control of neurogenesis by TH across animal phyla. We also discuss the role of thyroid disruptors on brain development in an evolutionary context.

Biological aspects and candidate biomarkers for rapid-cycling in bipolar disorder: A systematic review

Rapid-cycling bipolar disorder represents a frequent severe subtype of illness which has been associated with poor response to pharmacological treatment. Aim of the present article is to provide an updated review of biological markers associated with rapid-cycling bipolar disorder. A research in the main database sources has been conducted to identify relevant papers about the topic. Rapid-cycling bipolar disorder patients seem to have a more frequent family history for bipolar spectrum disorders (d range: 0.44-0.74) as well as an increased susceptibility to DNA damage or mRNA hypo-transcription (d range: 0.78-1.67) than non rapid-cycling ones. A susceptibility to hypothyroidism, which is exacerbated by treatment with lithium, is possible in rapid-cycling bipolar disorder, but further studies are needed to draw definitive conclusions. Rapid-cycling bipolar patients might have more insuline resistance as well as more severe brain changes in frontal areas (d range: 0.82-0.94) than non rapid-cycling ones. Many questions are still open about this topic. The first is whether the rapid-cycling is inheritable or is more generally the manifestation of a severe form of bipolar disorder. The second is whether some endocrine dysfunctions (diabetes and hypothyroidism) predispose to rapid-cycling or rapid-cycling is the consequence of drug treatment or medical comorbidities (e.g. obesity).

Thyroid Function and Ultrasonography Abnormalities in Lithium-Treated Bipolar Patients: A Cross-sectional Study with Healthy Controls

INTRODUCTION

Lithium has many effects on thyroid physiology. Although these side effects have been known for a long time, large sample studies of lithium-treated patients using ultrasonography are lacking. The aim of this study is to investigate the detailed thyroid morphologies, hormone levels, and antibodies of lithium-treated patients compared with healthy controls.

METHODS

This cross-sectional study involved 84 lithium-treated patients with bipolar disorder and 65 gender and age similar controls who had never been exposed to lithium. Subjects between 18 and 65 years of age were eligible for the study. Venous blood samples were acquired to determine the levels of free thyroxine (fT4), thyroid stimulating hormone (TSH), and thyroid antibodies; also, ultrasonographic examinations of the patients' thyroid glands were performed.

RESULTS

There were no statistically significant differences in smoking habits, known thyroid disease, thyroid medication use, familial thyroid disease, fT4 level, autoimmunity, thyroid nodule presence, or Hashimoto's thyroiditis between the lithium and control groups. The median TSH level and thyroid volume were significantly higher in the lithium group. In the lithium group, 14 cases (16.7%) of hypothyroidism, seven cases (8.3%) of subclinical hypothyroidism, and one case (1.2%) of subclinical hyperthyroidism were defined; in the control group, seven cases (10.8%) of hypothyroidism and two cases (3.1%) of subclinical hyperthyroidism were defined. Thyroid dysfunction, goiter, parenchymal abnormality, ultrasonographically defined thyroid abnormality, and thyroid disorder were found to be more prevalent in the lithium group. 90% of patients with goiter and 74.3% of patients with ultrasonographic pathologies were euthyroid.

CONCLUSION

It is important to note that 90% of the patients with goiter were euthyroid. This indicates that monitoring by blood test alone is insufficient. The prevalence rates of 47.6% for goiter and 83.3% for ultrasonographic pathology demonstrate that ultasonographic follow-up may be useful in lithium-treated patients. To determine whether routine ultrasonographic examination is necessary, large sample prospective studies are necessary due to the limitations of this study.

The International College of Neuro-Psychopharmacology (CINP) Treatment Guidelines for Bipolar Disorder in Adults (CINP-BD-2017), Part 2: Review, Grading of the Evidence, and a Precise Algorithm

Background

The current paper includes a systematic search of the literature, a detailed presentation of the results, and a grading of treatment options in terms of efficacy and tolerability/safety.

Material and Methods

The PRISMA method was used in the literature search with the combination of the words 'bipolar,' 'manic,' 'mania,' 'manic depression,' and 'manic depressive' with 'randomized,' and 'algorithms' with 'mania,' 'manic,' 'bipolar,' 'manic-depressive,' or 'manic depression.' Relevant web pages and review articles were also reviewed.

Results

The current report is based on the analysis of 57 guideline papers and 531 published papers related to RCTs, reviews, posthoc, or meta-analysis papers to March 25, 2016. The specific treatment options for acute mania, mixed episodes, acute bipolar depression, maintenance phase, psychotic and mixed features, anxiety, and rapid cycling were evaluated with regards to efficacy. Existing treatment guidelines were also reviewed. Finally, Tables reflecting efficacy and recommendation levels were created that led to the development of a precise algorithm that still has to prove its feasibility in everyday clinical practice.

Conclusions

A systematic literature search was conducted on the pharmacological treatment of bipolar disorder to identify all relevant random controlled trials pertaining to all aspects of bipolar disorder and graded the data according to a predetermined method to develop a precise treatment algorithm for management of various phases of bipolar disorder. It is important to note that the some of the recommendations in the treatment algorithm were based on the secondary outcome data from posthoc analyses.

Psychiatric and clinical correlates of rapid cycling bipolar disorder: a cross-sectional study

Objective:

Rapid cycling (RC) is a feature of bipolar disorder (BD) that has been associated with worse outcome and more severe disability. Our goal was to investigate the association of demographic and clinical factors with RC.

Methods:

We compared RC and non-rapid cycling (NRC) BD patients from the Brazilian Research Network in Bipolar Disorder (BRN-BD) regarding age at onset of BD; total number of episodes; previous number of manic, depressive, mixed, and hypomanic episodes; polarity of the first episode; gender; number of suicide attempts; number of lifetime hospitalizations and lifetime history of at least one hospitalization; family history of mood disorder; clinical comorbidities such as hypothyroidism, hyperthyroidism, seizures; and current use of medications such as lithium, anticonvulsants, antipsychotics, and antidepressants.

Results:

We studied 577 patients and found that 100 (17.3%) met the criteria for RC in the year before the investigation. RC patients had earlier age at onset, longer duration of disease, more lifetime depressive and manic episodes, higher number of suicide attempts, and higher rate antidepressant use.

Conclusion:

The presence of RC in the previous year was associated with specific clinical characteristics closely related to worse outcome in the course of BD.

Thyroglobulin antibodies and risk of readmission at one year in subjects with bipolar disorder

Thyroid autoimmunity has been proposed as an endophenotype for Bipolar Disorder (BD), although its relationship with clinical outcomes remains unclear. We aimed to determine whether thyroid autoimmune status (thyroperoxidase antibodies [TPO-Abs] and thyroglobulin antibodies [TG-Abs]) in BD is associated with a greater risk for readmission at one year. We studied 77 inpatients with BD admitted for an index manic or mixed episode. Serum thyroid antibodies (TPO-Abs and TG-Abs) were determined at admission. We compared the readmission risk at 1 year, based on patients׳ thyroid autoimmunity profile using survival analyses. Cox regression was used to control covariates. TG-Abs+ but not TPO-Abs+ was associated with a lower risk of relapse. The Kaplan-Meier mean estimated survival times were 341.6 days (CI95% 316.4-366.8) for the TG-Abs+ group and 261.9 days (CI95%: 221.8 to 302.0) for the TG-Abs- group. Cox proportional hazards regression indicated that subjects with TG-Abs+ were 3.7 (1/OR=1/0.27) times less likely to get admitted during the follow-up period than those with TG-Abs-. Our study suggests that an autoimmune biomarker in patients with BD (i.e., the presence of TG-Abs) is associated with a lower risk of psychiatric readmission after an index hospitalization for a manic or mixed episode.

Female vulnerability for thyroid function abnormality in bipolar disorder: role of lithium treatment

BACKGROUND

Previous studies have provided evidence of subtle thyroid hormone metabolism abnormalities in patients with mood disorders. Although these studies are informative, the precise role of the hypothalamic-pituitary-thyroid axis in bipolar disorder, especially in women, remains unclear. We sought to further corroborate thyroid function in patients with bipolar disorder in comparison to patients with other psychiatric, as well as non-psychiatric, diagnoses.

METHODS

In this retrospective, cross-sectional, naturalistic study, serum thyroid-stimulating hormone (TSH) levels in a total sample of 3,204 patients were compared. The study sample included patients with bipolar disorder (n = 469), unipolar depression (n = 615), and other psychiatric diagnoses (n = 999), patients from endocrinology clinics (n = 645), and patients from dermatology clinics (n = 476). Analyses were completed using two different normal ranges for TDH: a high normal range (0.4-5.0 μIU/mL) and a low normal range (0.3-3.0 μIU/mL).

RESULTS

Patients with bipolar disorder showed significantly higher serum TSH levels compared to all other groups. In women, the rate of above normal range TSH was highest in patients with bipolar disorder for both high (5.0 μIU/mL; 12.1%) and low (3.0 μIU/mL; 30.4%) upper normal limits. In patients with bipolar disorder, serum TSH levels did not differ significantly between different mood states. In the lithium-treated patients (n = 240), a significantly lower percentage of women (55.9%) compared to men (71.2%) fell within the 0.3-3.0 μIU/mL normal TSH window (p = 0.016). For the high normal range (0.4-5.0 μIU/mL), serum lithium levels above 0.8 mmol/L were associated with a significantly lower proportion of female patients (59.2%) falling within the normal range than male patients (88.9%). Non-lithium treatment was not associated with a gender difference.

CONCLUSIONS

Our findings show a higher rate of TSH abnormality in patients with bipolar disorder, particularly those taking lithium, compared to those with other psychiatric and medical conditions. Lithium-associated thyroid dysregulation occurs more frequently in female patients. Using the low normal range TSH values at follow-up can increase sensitivity in recognizing hyperthyroidism in lithium-treated female patients, and help in preventing the development of subclinical hypothyroidism and an adverse course of illness.

Gender differences in thyroid system function: relevance to bipolar disorder and its treatment

OBJECTIVES

Thyroid hormones play a critical role in the functioning of the adult brain, and thyroid diseases impair both mood and cognition. This paper reviews gender differences in thyroid system function that are relevant to the diagnosis and treatment of bipolar disorder.

METHODS

The study comprised a comprehensive literature review of gender differences in thyroid disease that are pertinent to mood disorders.

RESULTS

The prevalence of thyroid disease was found to be much higher in females than males, and to increase with age. The most commonly detected abnormality was subclinical hypothyroidism, which was found to occur in up to 20% of postmenopausal women. Females also had higher rates of thyroid autoimmunity. Individuals at risk for thyroid disease, such as adult females, may have had less ability to compensate for additional challenges to thyroid metabolism, including lithium treatment. Thyroid abnormalities were associated with a poorer response to standard treatments for mood disorders. Females with treatment-resistant mood disorders may have responded better than males to adjunctive therapy with thyroid hormones.

CONCLUSIONS

Disturbances of thyroid system function, which occur commonly in females, may complicate the diagnosis and treatment of mood disorders. In particular, this is clinically relevant during lithium treatment because lithium may impair vital thyroid metabolic pathways secondary to its anti-thyroid activity.

Mood and metabolic consequences of sleep deprivation as a potential endophenotype' in bipolar disorder

It has been commonly recognized that circadian rhythm and sleep/wake cycle are causally involved in bipolar disorder. There has been a paucity of systematic research considering the relations between sleep and mood states in bipolar disorder. The current study examines the possible influences of sleep deprivation on mood states and endocrine functions among first-degree relatives of patients with bipolar disorder and healthy controls. Blood samples were taken at two time points in the consecutive mornings at predeprivation and postdeprivation periods. Participants simultaneously completed the Profiles of Mood States at two time points after giving blood samples. Plasma T3 and TSH levels increased after total sleep deprivation in both groups. Sleep deprivation induced TSH levels were reversely associated with depression-dejection among healthy controls. A paradoxical effect was detected for only the first-degree relatives of the patients that changes in plasma cortisol levels negatively linked to depression-dejection and anger-hostility scores after total sleep deprivation. Plasma DHEA levels became correlated with vigor-activity scores after sleep deprivation among first-degree relatives of bipolar patients. On the contrary, significant associations of depression-dejection, anger-hostility, and confusion-bewilderment with the baseline plasma DHEA levels became statistically trivial in the postdeprivation period. Findings suggested that first-degree relatives of patients with bipolar disorder had completely distinct characteristics with respect to sleep deprivation induced responses in terms of associations between endocrine functions and mood states as compared to individuals whose relatives had no psychiatric problems. Considering the relationships between endocrine functions and mood states among relatives of the patients, it appears like sleep deprivation changes the receptor sensitivity which probably plays a pivotal role on mood outcomes among the first-degree relatives of patients with bipolar disorder.

No association between affective and behavioral dysregulation and parameters of thyroid function in youths

OBJECTIVE

Evidence from adults suggests that changes in thyroid function are associated with the development of bipolar disorder (BD) and severe mood dysregulation. A dysregulation profile based on the Child Behavior Checklist (CBCL-DP) describes a phenotype with severe mood problems in youth. The present study investigated whether altered thyroid functioning in youths is associated with the severe mood dysregulation symptoms characterized by the CBCL-DP.

METHODS

We analyzed the thyroid function data from 262 children and adolescents (n = 262 for serum TSH, n = 148 for free triiodothyronine [fT3] and n = 153 for free thyroxine [fT4]) with their CBCL-DP composite score. We created and compared high CBCL-DP and low CBCL-DP subgroups with regard to their serum TSH, fT3 and fT4 concentrations as well as the presence or absence of subclinical hypothyroidism.

RESULTS

We did not detect between-group differences in serum TSH, fT3 and fT4 concentrations, nor were there significant correlations between youths' CBCL-DP scores and their serum TSH, fT3 and fT4 concentrations for either the whole sample or any subgroup. Post-hoc power analyses indicated that adequate to moderate power existed to detect between-group differences in fT3 and fT4 concentrations, respectively, but that larger TSH samples would be required to detect the same differences in those concentrations.

LIMITATIONS

This study had a retrospective design, fewer females than males, and reduced power with respect to TSH concentrations.

CONCLUSIONS

The present investigation does not support the association between elevated serum-TSH concentrations and severe mood dysregulation in youths. However, these findings should be confirmed in future large-scale studies.

Thyroid functions and bipolar affective disorder

Accumulating evidence suggests that hypothalamo-pituitary-thyroid (HPT) axis dysfunction is relevant to the pathophysiology and clinical course of bipolar affective disorder. Hypothyroidism, either overt or more commonly subclinical, appears to the commonest abnormality found in bipolar disorder. The prevalence of thyroid dysfunction is also likely to be greater among patients with rapid cycling and other refractory forms of the disorder. Lithium-treatment has potent antithyroid effects and can induce hypothyroidism or exacerbate a preexisting hypothyroid state. Even minor perturbations of the HPT axis may affect the outcome of bipolar disorder, necessitating careful monitoring of thyroid functions of patients on treatment. Supplementation with high dose thyroxine can be considered in some patients with treatment-refractory bipolar disorder. Neurotransmitter, neuroimaging, and genetic studies have begun to provide clues, which could lead to an improved understanding of the thyroid-bipolar disorder connection, and more optimal ways of managing this potentially disabling condition.

Lithium and thyroid

One in 200 people receive lithium for treatment of bipolar disorder. The common clinical side effects of the drug are goitre in up to 40% and hypothyroidism in about 20%. Lithium increases thyroid autoimmunity if present before therapy. Treatment with levothyroxine is effective and lithium therapy should not be stopped. Lithium may cause hyperthyroidism due to thyroiditis or rarely Graves' disease. As lithium inhibits thyroid hormone release from the thyroid gland it can be used as an adjunct therapy in the management of severe hyperthyroidism. It also increases thyroidal radioiodine retention and may be effective in reducing administered activity in hyperthyroidism. There is no clinical benefit of lithium therapy in thyroid cancer. More research is required on the cellular proliferative effects of lithium as well as its impact on the immune system.

Lithium: updated human knowledge using an evidence-based approach: part III: clinical safety

Lithium use in mental diseases has changed over the years but remains a cornerstone of treatment in bipolar disorders. In two companion papers, we have reviewed existing (and especially recent) data on lithium efficacy and updated basic knowledge regarding the practical fundamentals of lithium therapy. The present paper reviews safety data on lithium available to date. Gastrointestinal pain or discomfort, diarrhoea, tremor, polyuria, nocturnal urination, weight gain, oedema, flattening of affect and exacerbation of psoriasis are typical complaints of patients receiving long-term lithium therapy. Renal involvement results in a reduced urinary concentrating capacity, expressed as obligate polyuria, with secondary thirst. With long-term therapy, this may result in nephrogenic diabetes insipidus. In addition, glomerular filtration rate falls slightly in about 20% of patients. The view that only a few patients receiving long-term lithium are at increased risk of glomerular impairment and progressive renal insufficiency should be regarded with caution. The risk is increased in case of concomitant diseases or medications. Lithium treatment may inhibit thyroid hormone release and induce goitre. Consequently, the prevalence of both overt and subclinical hypothyroidism is increased, with circulating thyroid auto-antibodies frequently being found. Much less commonly, thyrotoxicosis may also develop in association with lithium therapy. Long-term lithium treatment may also be associated with persistent hyperparathyroidism and hypercalcaemia, as well as with hypermagnesaemia. Overweight of up to 4-10 kg is found in approximately 30% of lithium-treated patients. Most neurological manifestations are benign, for example, the fine postural and/or action tremor present in 4-20% of patients. This is increased by high caffeine consumption and concomitant use of other psychotropic agents. A number of rare, potentially serious neurological adverse effects have been reported, including extrapyramidal symptoms, 'pseudotumour cerebri' or occasionally cerebellar symptoms. Severe neurological sequelae are exceptional. Cognitive disturbances are often mentioned as a lithium-related adverse effect. The few controlled studies do show a statistically significant negative effect of lithium on memory, vigilance, reaction time and tracking. There are frequent reports of mild effects of lithium on cognition at therapeutic serum concentrations. A number of deaths associated with lithium treatment have been reported. The most serious issue is that of non-accidental overdose, i.e. either long-term overdosage or acute overdose on long-term treatment. Progressive renal insufficiency, an exceptional complication of long-term lithium therapy, may also have a fatal outcome. In relation to pregnancy, lithium salts are rated as category D (positive evidence of risk). Therefore, prescription of lithium should be avoided during the first trimester of pregnancy unless the benefit to the mother exceeds the risk to the fetus. Although lithium transfer into breast milk is well established, the long-term fate of babies breast-fed by mothers receiving lithium therapy is unknown. Whether lithium therapy is safe in breast-feeding women is controversial. Although there is no absolute contraindication, it is known that the kidney is particularly sensitive to lithium just after birth. Intoxication in patients on long-term treatment with lithium in the absence of history of acute ingestion is not rare. Contributing factors include change in daily dose, long-term high dosage, kidney disease or drug interaction. In suspected cases, serum concentrations should be obtained early and repeatedly. In addition to supportive measures, haemodialysis is the treatment of choice for severe cases. Thorough knowledge of the limitations and drawbacks of lithium therapy is mandatory for its optimal use, especially at a time when its risk/benefit profile needs to be compared accurately with that of antiepileptic drugs and other mood stabilizing medications.

Circadian polymorphisms associated with affective disorders

BACKGROUND

Clinical symptoms of affective disorders, their response to light treatment, and sensitivity to other circadian interventions indicate that the circadian system has a role in mood disorders. Possibly the mechanisms involve circadian seasonal and photoperiodic mechanisms. Since genetic susceptibilities contribute a strong component to affective disorders, we explored whether circadian gene polymorphisms were associated with affective disorders in four complementary studies.

METHODS

Four groups of subjects were recruited from several sources: 1) bipolar proband-parent trios or sib-pair-parent nuclear families, 2) unrelated bipolar participants who had completed the BALM morningness-eveningness questionnaire, 3) sib pairs from the GenRed Project having at least one sib with early-onset recurrent unipolar depression, and 4) a sleep clinic patient group who frequently suffered from depression. Working mainly with the SNPlex assay system, from 2 to 198 polymorphisms in genes related to circadian function were genotyped in the participant groups. Associations with affective disorders were examined with TDT statistics for within-family comparisons. Quantitative trait associations were examined within the unrelated samples.

RESULTS

In NR1D1, rs2314339 was associated with bipolar disorder (P = 0.0005). Among the unrelated bipolar participants, 3 SNPs in PER3 and CSNK1E were associated with the BALM score. A PPARGC1B coding SNP, rs7732671, was associated with affective disorder with nominal significance in bipolar family groups and independently in unipolar sib pairs. In TEF, rs738499 was associated with unipolar depression; in a replication study, rs738499 was also associated with the QIDS-SR depression scale in the sleep clinic patient sample.

CONCLUSION

Along with anti-manic effects of lithium and the antidepressant effects of bright light, these findings suggest that perturbations of the circadian gene network at several levels may influence mood disorders, perhaps ultimately through regulation of MAOA and its modulation of dopamine transmission. Twenty-three associations of circadian polymorphisms with affective symptoms met nominal significance criteria (P < 0.05), whereas 15 would be expected by chance, indicating that many represented false discoveries (Type II errors). Some evidence of replication has been gathered, but more studies are needed to ascertain if circadian gene polymorphisms contribute to susceptibility to affective disorders.

The thyroid-brain interaction in thyroid disorders and mood disorders

Thyroid hormones play a critical role in the metabolic activity of the adult brain, and neuropsychiatric manifestations of thyroid disease have long been recognised. However, it is only recently that methodology such as functional neuroimaging has been available to facilitate investigation of thyroid hormone metabolism. Although the role of thyroid hormones in the adult brain is not yet specified, it is clear that without optimal thyroid function, mood disturbance, cognitive impairment and other psychiatric symptoms can emerge. Additionally, laboratory measurements of peripheral thyroid function may not adequately characterise central thyroid metabolism. Here, we review the relationship between thyroid hormone and neuropsychiatric symptoms in patients with primary thyroid disease and primary mood disorders.

Phenomic, convergent functional genomic, and biomarker studies in a stress-reactive genetic animal model of bipolar disorder and co-morbid alcoholism

We had previously identified the clock gene D-box binding protein (Dbp) as a potential candidate gene for bipolar disorder and for alcoholism, using a Convergent Functional Genomics (CFG) approach. Here we report that mice with a homozygous deletion of DBP have lower locomotor activity, blunted responses to stimulants, and gain less weight over time. In response to a chronic stress paradigm, these mice exhibit a diametric switch in these phenotypes. DBP knockout mice are also activated by sleep deprivation, similar to bipolar patients, and that activation is prevented by treatment with the mood stabilizer drug valproate. Moreover, these mice show increased alcohol intake following exposure to stress. Microarray studies of brain and blood reveal a pattern of gene expression changes that may explain the observed phenotypes. CFG analysis of the gene expression changes identified a series of novel candidate genes and blood biomarkers for bipolar disorder, alcoholism, and stress reactivity.

Rapid cycling bipolar disorder--diagnostic concepts

OBJECTIVES

This paper reviews the literature to examine the DSM-IV diagnostic criteria for rapid cycling in bipolar disorder.

METHODS

Studies on the clinical characteristics of rapid cycling bipolar disorder were reviewed. To identify relevant papers, literature searches using PubMed and MEDLINE were undertaken.

RESULTS

First observed in the prepharmacologic era, rapid cycling subsequently has been associated with a relatively poor response to pharmacologic treatment. Rapid cycling can be conceptualized as either a high frequency of episodes of any polarity or as a temporal sequence of episodes of opposite polarity. The DSM-IV defines rapid cycling as a course specifier, signifying at least four episodes of major depression, mania, mixed mania, or hypomania in the past year, occurring in any combination or order. It is estimated that rapid cycling is present in about 12-24% of patients at specialized mood disorder clinics. However, apart from episode frequency, studies over the past 30 years have been unable to determine clinical characteristics that define patients with rapid cycling as a specific subgroup. Furthermore, rapid cycling is a transient phenomenon in many patients.

CONCLUSIONS

While a dimensional approach to episode frequency as a continuum between the extremes of no cycling and continuous cycling may be more appropriate and provide a framework to include ultra-rapid and ultradian cycling, the evidence does not exist today to refine the DSM-IV definition in a less arbitrary manner. Continued use of the DSM-IV definition also enables comparisons between past and future studies, and it should be included in the next release of the ICD. Further scientific investigation into rapid cycling is needed. In addition to improving the diagnostic criteria, insight into neurophysiologic mechanisms of mood switching and episode frequency may have important implications for clinical care.

Rapid cycling bipolar disorder: clinical characteristics and treatment options

Approximately one of six patients who seek treatment for bipolar disorder present with a rapid cycling pattern. In comparison with other patients who have bipolar disorder, these individuals experience more affective morbidity in both the immediate and distant future and are more likely to experience recurrences despite treatment with lithium or anticonvulsants. Particular care should be given to distinguishing rapid cycling bipolar disorder from attention-deficit hyperactivity disorder in children or adolescents and from borderline personality disorder in adults. Perhaps four of five cases of rapid cycling resolve within a year, but the pattern may persist for many years in the remaining patients. As with bipolar disorder in general, depressive symptoms produce the most morbidity over time. Controlled studies have not established that antidepressants provoke switching or rapid cycling, but neither have they been shown consistently to have benefits in bipolar illness. Successful management will often require a sequence of trials with mood stabilizer drugs, beginning with lithium in treatment-naive patients. Efforts to minimise adverse effects, and the recognition that full benefits may not be apparent for several months, will make the premature abandonment of a potentially helpful treatment less likely. Placebo-controlled studies so far provide the most support for the use of lithium and lamotrigine as prophylactic agents. The combination of lithium and carbamazepine, valproate or lamotrigine for maintenance has some support from controlled studies, as does the adjunctive use of olanzapine.

Rapid antidepressant response after nocturnal TRH administration in patients with bipolar type I and bipolar type II major depression

BACKGROUND

Thyrotropin-releasing hormone (TRH) is a tripeptide that produces endocrine and behavioral effects in animals and humans. Some studies have shown transient antidepressant activity after morning administration of TRH. We hypothesized that nocturnal administration of TRH, when the circadian sensitivity of the TRH receptor is at its peak, may result in a more robust antidepressant effect.

METHODS

Twenty patients with bipolar (BP) type I or BP type II major depressive episode (MDE) were given nocturnal intravenous TRH 500 microg (n = 10) or saline (n = 10) at midnight in a randomized, double-blind fashion. Antidepressant activity was assessed using the Hamilton Depression Rating (HAM-D), Young Mania Rating (YMR), and Profile of Mood (POMS) scales over a 48-hour period. Thyrotropin (TSH), total T4, and free T3 concentrations were measured before and after TRH administration. Data were analyzed using chi test, Fisher exact test, and repeated-measures ANOVA.

RESULTS

Sixty percent of the TRH group and 10% of the saline group showed a > or =50% reduction in baseline total HAM-D score within 24 hours (P = 0.03). HAM-D ratings fell by an average of 52% after TRH administration versus 12% after saline administration (P = 0.038). There was a modest increase in YMR scores after TRH compared with saline (P < 0.032). No manic or hypomanic episodes were observed. Antidepressant effects of TRH lasted up to 48 hours. There was no correlation between DeltaTSH, DeltaT4, or DeltaT3 measures after TRH (or saline) administration and the change in HAM-D scores.

CONCLUSIONS

Nocturnal TRH administration may produce a rapid antidepressant effect in some patients with BP I and BP II MDE.

Exclusion of non-synonymous SNPs and a polyglutamine tract in SMRT/N-CoR2 as common deleterious mutation for bipolar disorder in the Sagnenay-Lac-St-Jean population

Bipolar disorder (BP) is a psychiatric illness with both genetic and environmental components occurring with a prevalence of slightly more than 1%. Our previous linkage and case/control studies have pointed to a susceptibility locus for BP in the 12q24.31 chromosomal region. Here, we investigated the possible involvement of the SMRT/N-CoR2 gene, which encodes for the nuclear receptor co-repressor 2. SMRT/N-CoR2 was retained as a candidate gene for BP because of its location within our candidate gene region and its interactions with thyroid hormone receptors. We screened SMRT/N-CoR2 for the presence of polymorphism/mutation in coding sequences and exon-intron junctions. Four non-synonymous SNPs and a polyglutamine tract (CAG repeat) in the coding exon 14 were analyzed in a case/control sample from the Saguenay-Lac-St-Jean (SLSJ) area of Quebec (213 cases and 214 controls). Our data indicated no significant allelic/genotypic association between any of the five mutations and bipolar phenotype when they were considered either individually or as haplotypes. Finally, the CAG repeat observed in SMRT/N-CoR2 did not demonstrate allelic instability and consequently it is unlikely that this polymorphism could be involved in the anticipation phenomenon reported for BP.