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

Involvement of the glycogen synthase kinase-3 signaling pathway in TBI pathology and neurocognitive outcome

BACKGROUND

Traumatic brain injury (TBI) sets in motion cascades of biochemical changes that result in delayed cell death and altered neuronal architecture. Studies have demonstrated that inhibition of glycogen synthase kinase-3 (GSK-3) effectively reduces apoptosis following a number of stimuli. The Wnt family of proteins, and growth factors are two major factors that regulate GSK-3 activity. In the absence of stimuli, GSK-3 is constitutively active and is complexed with Axin, adenomatous polyposis coli (APC), and casein kinase Iα (CK1α) and phosphorylates ß-Catenin leading to its degradation. Binding of Wnt to Frizzled receptors causes the translocation of GSK-3 to the plasma membrane, where it phosphorylates and inactivates the Frizzled co-receptor lipoprotein-related protein 6 (LRP6). Furthermore, the translocation of GSK-3 reduces ß-Catenin phosphorylation and degradation, leading to ß-Catenin accumulation and gene expression. Growth factors activate Akt, which in turn inhibits GSK-3 activity by direct phosphorylation, leading to a reduction in apoptosis.

METHODOLOGY/PRINCIPAL FINDINGS

Using a rodent model, we found that TBI caused a rapid, but transient, increase in LRP6 phosphorylation that is followed by a modest decrease in ß-Catenin phosphorylation. Phospho-GSK-3β immunoreactivity was found to increase three days post injury, a time point at which increased Akt activity following TBI has been observed. Lithium influences several neurochemical cascades, including inhibiting GSK-3. When the efficacy of daily lithium was assessed, reduced hippocampal neuronal cell loss and learning and memory improvements were observed. These influences were partially mimicked by administration of the GSK-3-selective inhibitor SB-216763, as this drug resulted in improved motor function, but only a modest improvement in memory retention and no overt neuroprotection.

CONCLUSION/SIGNIFICANCE

Taken together, our findings suggest that selective inhibition of GSK-3 may offer partial cognitive improvement. As a broad spectrum inhibitor of GSK-3, lithium offers neuroprotection and robust cognitive improvement, supporting its clinical testing as a treatment for TBI.

Do Thyroid Disrupting Chemicals Influence Foetal Development during Pregnancy?

Maternal euthyroidism during pregnancy is crucial for normal development and, in particular, neurodevelopment of the foetus. Up to 3.5 percent of pregnant women suffer from hypothyroidism. Industrial use of various chemicals—endocrine disrupting chemicals (EDCs)—has been shown to cause almost constant exposure of humans with possible harmful influence on health and hormone regulation. EDCs may affect thyroid hormone homeostasis by different mechanisms, and though the effect of each chemical seems scarce, the added effects may cause inappropriate consequences on, for example, foetal neurodevelopment. This paper focuses on thyroid hormone influence on foetal development in relation to the chemicals suspected of thyroid disrupting properties with possible interactions with maternal thyroid homeostasis. Knowledge of the effects is expected to impact the general debate on the use of these chemicals. However, more studies are needed to elucidate the issue, since human studies are scarce.

Psychiatric disorders and treatment in low-income pregnant women

AIMS

This study estimated the prevalence of twenty-two 12-month and lifetime psychiatric disorders in a sample of 744 low-income pregnant women and the frequency that women with psychiatric disorders received treatment.

METHOD

To identify psychiatric disorders, the Diagnostic Interview Schedule (DIS) was administered to Medicaid or Medicaid-eligible pregnant women enrolled in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC). The sample was stratified by the rural or urban location of the WIC sites in southeastern Missouri and the city of St. Louis. Eligible women were enrolled at each site until their numbers were proportional to the racial distribution of African American and Caucasian pregnant women served there.

RESULTS

The 12-month prevalence of one or more psychiatric disorders was 30.9%. Most common were affective disorders (13.6%), particularly major depressive disorder (8.2%) and bipolar I disorder (5.2%). Only 24.3% of those with a psychiatric disorder reported that they received treatment in the past year. Lifetime prevalence of at least one disorder was 45.6%, with affective disorders being the most frequent (23.5%). Caucasian women were more likely than African Americans to have at least one 12-month disorder, with the difference largely accounted for by nicotine dependence. Higher prevalence of lifetime disorders was also found in Caucasian women, particularly affective disorders and substance use disorders. There were no differences in the prevalence of 12-month or lifetime psychiatric disorders by the urban or rural residence of subjects.

CONCLUSIONS

With nearly one third of pregnant women meeting criteria for a 12-month psychiatric disorder and only one fourth receiving any type of mental health treatment, comprehensive psychiatric screening during pregnancy is needed along with appropriate treatment.

A critical appraisal of treatments for bipolar disorder

Recovery-the absence of all abnormal mood symptoms-is the goal of treatment for bipolar disorder. Unfortunately, a minority of people suffering from bipolar disorder achieve sustained recovery. Improving recovery rates for this population will require clinicians in the primary care setting to be familiar with appropriate treatments for acute bipolar mania and depression and for the maintenance phase. Efficacy and tolerability of pharmacotherapeutic and psychotherapeutic options for all phases of treatment and each type of mood episode are discussed. Primary care physicians are encouraged to avoid prescribing antidepressant monotherapy for any patient with depression and a history of mania or hypomania.

The many faces of tau

While the microtubule-binding capacity of the protein tau has been known for many years, new functions of tau in signaling and cytoskeletal organization have recently emerged. In this review, we highlight these functions and the potential roles of tau in neurodegenerative disease. We also discuss the therapeutic potential of drugs targeting various aspects of tau biology.

Mood stabilizers for patients with bipolar disorder: the state of the art

Bipolar disorder (BD) is a prevalent and disabling condition, often comorbid with other medical and psychiatric conditions and frequently misdiagnosed. International treatment guidelines for BD recommend the use of mood stabilizers - either in monotherapy or in association - as the gold standard in both acute and long-term therapy. Commonly used in the clinical practice of BD, mood stabilizers have represented an evolving field over the last few years. The concept of stabilization, in fact, has been stressed as the ultimate objective of the treatment of BD, given the chronic and recurrent nature of the illness, which accounts for its significant levels of impairment and disability. To date, different compounds are included within the broad class of mood stabilizers, with lithium, anticonvulsants and, more recently, atypical antipsychotics being the most representative agents. This article is aimed at providing an updated review of the available literature in relation to the role of mood stabilizers in BD, with particular emphasis on their mechanism of action, main clinical aspects and specific use in the different phases of BD treatment, according to the most recently published international treatment guidelines.

Lithium in drinking water and thyroid function

BACKGROUND

High concentrations of lithium in drinking water were previously discovered in the Argentinean Andes Mountains. Lithium is used worldwide for treatment of bipolar disorder and treatment-resistant depression. One known side effect is altered thyroid function.

OBJECTIVES

We assessed associations between exposure to lithium from drinking water and other environmental sources and thyroid function.

METHODS

Women (n=202) were recruited in four Andean villages in northern Argentina. Lithium exposure was assessed based on concentrations in spot urine samples, measured by inductively coupled plasma mass spectrometry. Thyroid function was evaluated by plasma free thyroxine (T4) and pituitary gland thyroid-stimulating hormone (TSH), analyzed by routine immunometric methods.

RESULTS

The median urinary lithium concentration was 3,910 μg/L (5th, 95th percentiles, 270 μg/L, 10,400 μg/L). Median plasma concentrations (5th, 95th percentiles) of T4 and TSH were 17 pmol/L (13 pmol/L, 21 pmol/L) and 1.9 mIU/L, (0.68 mIU/L, 4.9 mIU/L), respectively. Urine lithium was inversely associated with T4 [β for a 1,000-μg/L increase=-0.19; 95% confidence interval (CI), -0.31 to -0.068; p=0.002] and positively associated with TSH (β=0.096; 95% CI, 0.033 to 0.16; p=0.003). Both associations persisted after adjustment (for T4, β=-0.17; 95% CI, -0.32 to -0.015; p=0.032; for TSH: β=0.089; 95% CI, 0.024 to 0.15; p=0.007). Urine selenium was positively associated with T4 (adjusted T4 for a 1 μg/L increase: β=0.041; 95% CI, 0.012 to 0.071; p=0.006).

CONCLUSIONS

Exposure to lithium via drinking water and other environmental sources may affect thyroid function, consistent with known side effects of medical treatment with lithium. This stresses the need to screen for lithium in all drinking water sources.

A case of mania due to cryptococcal meningitis, successfully treated with adjunctive olanzapine, in a patient with acquired immunodeficiency syndrome

We report on the case of a patient with acquired immune deficiency syndrome- and Cryptococcus neoformans meningitis-related mania in which olanzapine was successfully used adjunctively and transiently to antifungal therapy.

The lithiumeter: a measured approach

BACKGROUND

Lithium has long been recognised for its mood-stabilizing effects in the management of bipolar disorder (BD) but in practice its use has been limited because of real and 'imagined' concerns. This article addresses the need for lithium to be measured with respect to its clinical and functional effects. It introduces a visual scale, termed lithiumeter, which captures the optimal lithium plasma levels for the treatment of BD.

METHODS

  Key words pertaining to lithium's administration, dosing, and side effects as well as its efficacy in acute and long-term treatment of BD were used to conduct an electronic search of the literature. Relevant articles were identified by the authors and reviewed.

RESULTS

This paper outlines the considerations necessary prior to initiating lithium therapy and provides a guide to monitoring lithium plasma levels. Current recommendations for optimal plasma lithium levels in the management of BD are then discussed with respect to indications for use in the acute phases of the illness and maintenance therapy. The risks associated with lithium treatment are also discussed.

CONCLUSIONS

The lithiumeter provides a practical guide of optimal lithium levels for the clinical management of BD.

Optimal frequency of lithium administration in the treatment of bipolar disorder: clinical and dosing considerations

Bipolar disorder is a recurrent chronic illness distinguished by periods of mania and depression. Lithium has been used for about 60 years as a 'mood stabilizer' for bipolar disorder with proven efficacy in preventing relapse of both mania and depression. Despite its long history and ongoing use in current management of bipolar disorder, the optimal dosing of lithium is still the subject of ongoing debate. This article aims to evaluate different dosing schedules, in the light of the unique pharmacokinetic and pharmacodynamic properties of lithium, as well as its adverse-effect and toxicity profiles. This is all the more important given the narrow therapeutic index of lithium. Current recommendations mostly advocate that lithium be administered in multiple daily doses. However, single daily or alternate daily schedules may be viable options for administration. Multiple daily schedules are thought to be advantageous in maintaining more constant plasma lithium concentrations than single daily regimens, which are associated with significant fluctuations throughout the day. When comparing these two schedules with respect to plasma lithium concentrations, adverse-effect profiles and recurrence of symptoms, there are no significant differences between the two regimens. In fact, a single daily regimen may have added advantages in reducing the risk of long-term renal damage and increasing compliance. The evidence for alternate daily dosing is somewhat varied with regard to symptom recurrence; however, this schedule has been shown to be associated with decreased adverse effects, and further research into this issue is therefore warranted. Presently, therefore, clinicians should consider single daily administration of lithium to potentially minimize adverse effects and enhance compliance.

Antidepressant drugs and breastfeeding: a review of the literature

The use of antidepressants in breastfeeding mothers is controversial: Manufacters often routinely discourage breastfeeding for the nursing mother despite the well-known positive impact that breastfeeding carries on the health of the nursing infant and on his or her family and society. We conducted a systematic review of drugs commonly used in the treatment of postpartum depression. For every single drug two sets of data were provided: (1) selected pharmacokinetic characteristics such as half-life, milk-to-plasma ratio, protein binding, and oral bioavailability and (2) information about lactational risk, according to some authoritative sources of the literature: Drugs in Pregnancy and Lactation edited by Briggs et al. (Lippincott Williams, Philadelphia, 2008), Medications and Mothers' Milk by Hale (Hale Publishing, Amarillo, TX, 2010), and the LactMed database of TOXNET ( www.pubmed.gov ; accessed June 2010). Notwithstanding a certain variability of advice, we found that (1) knowledge of pharmacokinetic characteristics are scarcely useful to assess safety and (2) the majority of antidepressants are not usually contraindicated: (a) Selective serotinin reuptake inhibitors and nortryptiline have a better safety profile during lactation, (b) fluoxetine must be used carefully, (c) the tricyclic doxepine and the atypical nefazodone should better be avoided, and (d) lithium, usually considered as contraindicated, has been recently rehabilitated.

High-level exposure to lithium, boron, cesium, and arsenic via drinking water in the Andes of northern Argentina

Elevated concentrations of arsenic in drinking water are common worldwide, however, little is known about the presence of other potentially toxic elements. We analyzed 31 different elements in drinking water collected in San Antonio de los Cobres and five surrounding Andean villages in Argentina, and in urine of the inhabitants, using ICP-MS. Besides confirmation of elevated arsenic concentrations in the drinking water (up to 210 microg/L), we found remarkably high concentrations of lithium (highest 1000 microg/L), cesium (320 microg/L), rubidium (47 microg/L), and boron (5950 microg/L). Similarly elevated concentrations of arsenic, lithium, cesium, and boron were found in urine of the studied women (N=198): village median values ranged from 26 to 266 microg/L of arsenic, 340 to 4550 microg/L of lithium, 34 to 531 microg/L of cesium, and 2980 to 16,560 microg/L of boron. There is an apparent risk of toxic effects of long-term exposure to several of the elements, and studies on associations with adverse human health effects are warranted, particularly considering the combined, life-long exposure. Because of the observed wide range of concentrations, all water sources used for drinking water should be screened for a large number of elements; obviously, this applies to all drinking water sources globally.

Treatment of cluster headache in pregnancy and lactation

Cluster headache (CH) is a neurovascular headache syndrome characterized by headache attacks that occur with a circadian and circannual periodicity. The calculated prevalence of CH in reproductive-aged women is 7.5 of 100,000 women. Although data suggest that CH during pregnancy is a relatively rare condition, when it does occur, attacks remain unchanged in character and severity in the majority of patients. Thus, treatment of CH in pregnant and lactating women may remain a significant therapeutic challenge. This manuscript briefly reviews the epidemiology of CH in women, and then focuses on treatment options for both acute and preventative management of CH in pregnant and lactating women.

Assessment of safety, tolerability and effectiveness of adjunctive aripiprazole to lithium/valproate in bipolar mania: a 46-week, open-label extension following a 6-week double-blind study

OBJECTIVE

This study evaluated the long-term tolerability and effectiveness of aripiprazole adjunctive to lithium or valproate in partial responders with bipolar mania.

METHODS

Completers of a 6-week double-blind comparison of adjunctive aripiprazole versus placebo in bipolar mania partially responsive to lithium or valproate monotherapy could enter a 46-week extension treatment with open-label adjunctive aripiprazole plus lithium (ARI + LI) or valproate (ARI + VAL). Safety, efficacy and functioning were assessed.

CLINICAL TRIAL REGISTRATION

CN138-134LT: Study of Aripiprazole in Patients With Bipolar I Disorder; ID number: NCT00257972; registry: www.clinicaltrials.gov.

RESULTS

In total, 283 (ARI + LI n = 108; ARI + VAL n = 175) patients entered and 146 (ARI + LI n = 55; ARI + VAL n = 91) completed the 46-week, open-label extension. Frequently reported adverse events (AEs) that occurred with ARI + LI vs. ARI + VAL were: tremor (17.0% vs. 12.1%), akathisia (6.6% vs. 8.6%), headache (6.6% vs. 4.0%), insomnia (9.4% vs. 10.3%), depression (7.5% vs. 9.2%) and weight increase (11.3% vs. 8.6%). Extrapyramidal symptom-related AEs occurred in 24 (22.6%) ARI + LI- and 38 (21.8%) ARI + VAL-treated patients, with eight discontinuations. The majority of new-onset events of akathisia and insomnia occurred early. Mean (SE) weight change from double-blind endpoint to Week 46 (LOCF) was 2.3 (0.6) kg with ARI + LI and 2.0 (0.4) kg with ARI + VAL. Significant improvements from baseline over the 52 weeks (LOCF) occurred with ARI + LI and ARI + VAL on mean (95%CI) YMRS total score (-16.5 [-18.1; -14.8] and -17.6 [-18.9; -16.3], both p < 0.001 vs. baseline) and MADRS total score (-1.7 [-3.3; -0.1], p < 0.05 vs. baseline vs. -2.7 [-4.0; -1.4], p < 0.001 vs. baseline). Over the 46-week extension, continued aripiprazole provided continued YMRS improvement with ARI + LI (-2.9) and ARI + VAL (-3.3), while mean MADRS total changes were +1.1 and +1.0, respectively, and LIFE-RIFT changes were 0.2 and -0.5, respectively.

CONCLUSIONS

Long-term aripiprazole adjunctive to lithium/valproate in bipolar mania was safe and well tolerated. Improvements in manic symptoms and functioning were maintained. Aripiprazole, adjunctive to either lithium or valproate, appeared to be equally safe and effective combinations for the treatment of bipolar disorder.

LIMITATIONS

As an open-label extension study with a low completion rate, a conservative interpretation of the findings is warranted. Additionally, the study population was not randomly selected but chosen at the discretion of the investigator, and patients did not maintain therapeutic levels of their mood stabiliser consistently.