Lithium treatment and thyroid abnormalities

Ultrasonically determined thyroid volume and thyroid functions in lithium-naïve and lithium-treated patients with bipolar disorder: a cross-sectional and longitudinal study

OBJECTIVE

This study investigated thyroid volume, hormone levels and antibodies in long-term lithium-treated and lithium-naïve bipolar patients, some of whom underwent prospective follow-up evaluations.

METHODS

Fourteen lithium-naïve patients, 13 long-term lithium-treated patients diagnosed with bipolar disorder and 12 healthy controls were included. Seven lithium-naïve patients were followed-up during their lithium receiving period (range 6-9 months). Thyroid volume and serum levels of thyroid hormones and antibodies were measured once in the long-term lithium-treated patients and controls, and twice in the lithium-naïve patients, i.e. before and after lithium treatment.

RESULTS

Mean thyroid volumes in the lithium-naïve patients were significantly higher than those in the controls. Long-term lithium-treated patients had significantly higher total thyroid volume than the lithium-naïve patients and the controls. Total thyroid volume in the patients after the lithium treatment was significantly higher than that before. Serum free thyroxine (fT4) levels in the long-term lithium-treated patients were lower than those in the lithium-naïve patients and the controls. In the lithium-naïve patients, after lithium treatment, free triiodothyronine (fT3) levels were lower, and thyroid stimulating hormone (TSH) levels were higher compared to those before lithium treatment.

CONCLUSIONS

The results suggest that thyroid enlargement and some alterations in thyroid hormones in bipolar patients may present even before lithium treatment and increase further with lithium treatment.

Adverse endocrine and metabolic effects of psychotropic drugs: selective clinical review

The article critically reviews selected, clinically significant, adverse endocrine and metabolic effects associated with psychotropic drug treatments, including hyperprolactinaemia, hyponatraemia, diabetes insipidus, hypothyroidism, hyperparathyroidism, sexual dysfunction and virilization, weight loss, weight gain and metabolic syndrome (type 2 diabetes mellitus, dyslipidaemia and hypertension). Such effects are prevalent and complex, but can be managed clinically when recognized. They encourage continued critical assessment of benefits versus risks of psychotropic drugs and underscore the importance of close coordination of psychiatric and general medical care to improve long-term health of psychiatric patients. Options for management of hyperprolactinaemia include lowering doses, switching to agents such as aripiprazole, clozapine or quetiapine, managing associated osteoporosis, carefully considering the use of dopamine receptor agonists and ruling out stress, oral contraceptive use and hypothyroidism as contributing factors. Disorders of water homeostasis may include syndrome of inappropriate antidiuretic hormone (SIADH), managed by water restriction or slow replacement by hypertonic saline along with drug discontinuation. Safe management of diabetes insipidus, commonly associated with lithium, involves switching mood stabilizer and consideration of potassium-sparing diuretics. Clinical hypothyroidism may be a more useful marker than absolute cut-offs of hormone values, and may be associated with quetiapine, antidepressant and lithium use, and managed by thyroxine replacement. Hyper-parathyroidism requires comprehensive medical evaluation for occult tumours. Hypocalcaemia, along with multiple other psychiatric and medical causes, may result in decreased bone density and require evaluation and management. Strategies for reducing sexual dysfunction with psychotropics remain largely unsatisfactory. Finally, management strategies for obesity and metabolic syndrome are reviewed in light of the recent expert guidelines, including risk assessment and treatments, such as monoamine transport inhibitors, anticonvulsants and cannabinoid receptor antagonists, as well as lifestyle changes.

The International Society for Bipolar Disorders (ISBD) consensus guidelines for the safety monitoring of bipolar disorder treatments

OBJECTIVES

Safety monitoring is an important aspect of bipolar disorder treatment, as mood-stabilising medications have potentially serious side effects, some of which may also aggravate existing medical comorbidities. This paper sets out the International Society for Bipolar Disorders (ISBD) guidelines for the safety monitoring of widely used agents in the treatment of bipolar disorder. These guidelines aim to provide recommendations that take into consideration the balance between safety and cost-effectiveness, to highlight iatrogenic and preventive clinical issues, and to facilitate the broad implementation of therapeutic safety monitoring as a standard component of treatment for bipolar disorder.

METHODS

These guidelines were developed by an ISBD workgroup, headed by the senior author (MB), through an iterative process of serial consensus-based revisions. After this, feedback from a multidisciplinary group of health professionals on the applicability of these guidelines was sought to develop the final recommendations.

RESULTS

General safety monitoring recommendations for all bipolar disorder patients receiving treatment and specific monitoring recommendations for individual agents are outlined.

CONCLUSIONS

These guidelines are derived from evolving and often indirect data, with minimal empirical cost-effectiveness data available to provide guidance. These guidelines will therefore need to be modified to adapt to different clinical settings and health resources. Clinical acumen and vigilance remain critical ingredients for safe treatment practice.

Medical complications of psychiatric treatment

Psychiatric medications are frequently an essential component of care for critically ill patients. Their use may lead to medical complications, however, as a result of (1) direct toxicity from psychotropic medications, (2) drug-drug interactions, or (3) intoxication or withdrawal states. These complications may be a nuisance (eg, dry mouth and nausea) or serious and life-threatening (eg, neuroleptic malignant syndrome and cardiac arrhythmias). This article addresses the most important medical complications (organized by organ systems) of psychiatric treatment.

Environmental factors and genetic background that interact to cause autoimmune thyroid disease

PURPOSE OF REVIEW

To provide an updated list of genetic and environmental causative factors of autoimmune thyroid disease, and report about the recent discoveries concerning their interaction in the pathogenesis of thyroid autoimmunity.

RECENT FINDINGS

Although significant discoveries have been made on genetic and environmental factors underlying the development of autoimmune thyroid disease, few data are available about the mechanisms by which they interact. The most interesting news in this field comes from research on molecular mimicry between microbial antigens and thyroid autoantigens. The molecular mimicry model postulates that, in predisposed subjects, a microbial antigen could trigger autoimmunity because of its structural similarity to an autoantigen of the host, and is a paradigmatic example of the multifactorial interaction of several genes and environmental factors to cause autoimmune diseases, including thyroid diseases.

SUMMARY

Recent findings help us to better understand the functional mechanisms of the immune system, which are still only partially known. Beyond the scientific interest, this knowledge has immediate repercussions on clinical practice because it can suggest possible therapeutic targets for new treatments, as well as better and more specific uses of currently available drugs and resources.

Therapeutic drug and cardiovascular disease risk monitoring in patients with bipolar disorder

OBJECTIVES

We assessed whether patients with bipolar disorder received serum drug level and toxicity monitoring for mood stabilizers and assessment of cardiovascular disease (CVD)-related risk factors attributed to atypical antipsychotic medications.

METHODS

A population-based study of individuals with bipolar disorder was conducted between July 2004 and July 2006. Based on American Psychiatric and American Diabetes Association guidelines, we assessed whether patients received recommended drug level and toxicity monitoring tests on or within 6 months for mood stabilizers, and lipid and glucose tests for atypical antipsychotics. Multivariable regression was used to determine the patient factors associated with receipt of lab tests.

RESULTS

Of the 435 patients (mean age=49 years, 14.3% female, 22.8% nonwhite), 60.3% were currently prescribed mood stabilizers and 65.5% were prescribed atypical antipsychotics. Overall, 39.7% received a serum drug level for mood stabilizers, 38.8% received a thyroid function test for lithium, and the majority (71.4%-75.9%) received complete blood counts and hepatic function tests for valproate or carbamazepine. About half of patients prescribed atypical antipsychotics received cholesterol counts (49.6%), and 68.7% received serum glucose levels. After adjusting for patient factors, women prescribed atypical antipsychotics were less likely than men to receive cholesterol counts (OR=0.43; p<0.05).

LIMITATIONS

Single-site retrospective study and a relatively short observation period.

CONCLUSIONS

About half of patients received recommended lab tests for mood stabilizers and atypical antipsychotics. Additional research regarding whether the receipt of these lab tests is associated with improved outcomes will inform efforts to improve quality of care related to drug toxicities and CVD risk factors in patients with bipolar disorder.

Fifteen-year follow-up of thyroid function in lithium patients

OBJECTIVE

To study prospectively the course of clinically relevant thyroid dysfunction in a cohort of patients on long-term lithium treatment.

METHOD

Patients (no.=150) who had undergone a cross-sectional evaluation of their thyroid function in 1989, when they were at different stages of lithium treatment, were followed up for thyroid circulating thyroid antibodies, hypothyroidism, hyperthyroidism, and thyroidectomy, during a further period of lithium exposure of up to 15 yr.

RESULTS

Annual rates of newly developed circulating thyroid antibodies and hypothyroidism were 1.7 and 1.5%, respectively. Subjects with thyroid antibodies had a higher chance of requiring substitution treatment with levothyroxine for hypothyroidism compared with subjects with no evidence of thyroid antibodies (6.4% annual rate compared to 0.8%; relative risk: 8.4; 95% confidence interval: 2.9-24.0). One case of hyperthyroidism was observed over 976 patient-yr. Three patients underwent thyroidectomy during followup (two for multinodular goiter and one for multicentric papillary carcinoma).

CONCLUSIONS

Lithium may be associated with hypothyroidism in particular in the presence of circulating thyroid antibodies. Incidence of thyroid antibodies is comparable with that reported for the general population. Hyperthyroidism and thyroid cancer are rare.

Pharmacological treatment of bipolar disorder among children and adolescents

There is growing recognition that bipolar disorder frequently first presents in adolescence. Preadolescents with volatile behavior and severe mood swings also comprise a large group of patients whose difficulties may lie within the bipolar spectrum. However, the preponderance of scientific effort and clinical trials for this condition has focused on adults. This review summarizes the complexity of bipolar disorder and diagnosis of the disease among young people. It proceeds to review the principles of pharmacotherapy, assess current treatment options and to highlight areas where evidence-based guidance is lacking. Recent developments have enlarged the range of potential treatments for bipolar disorder. Nonetheless, differences in the phenomenology, course and sequelae of bipolar disorder among young people compel greater attention to the benefits and liabilities of therapy for those affected by this illness' early onset. By summarizing current research and opinion on diagnostic issues and treatment approaches, this review aims to provide an update on a clinically important yet controversial topic.