Lithium: updated human knowledge using an evidence-based approach: Part I: Clinical efficacy in bipolar disorder

Machine learning for predicting medical outcomes associated with acute lithium poisoning

The use of machine learning algorithms and artificial intelligence in medicine has attracted significant interest due to its ability to aid in predicting medical outcomes. This study aimed to evaluate the effectiveness of the random forest algorithm in predicting medical outcomes related to acute lithium toxicity. We analyzed cases recorded in the National Poison Data System (NPDS) between January 1, 2014, and December 31, 2018. We highlighted instances of acute lithium toxicity in patients with ages ranging from 0 to 89 years. A random forest model was employed to predict serious medical outcomes, including those with a major effect, moderate effect, or death. Predictions were made using the pre-defined NPDS coding criteria. The model's predictive performance was assessed by computing accuracy, recall (sensitivity), and F1-score. Of the 11,525 reported cases of lithium poisoning documented during the study, 2,760 cases were categorized as acute lithium overdose. One hundred thirty-nine individuals experienced severe outcomes, whereas 2,621 patients endured minor outcomes. The random forest model exhibited exceptional accuracy and F1-scores, achieving values of 99%, 98%, and 98% for the training, validation, and test datasets, respectively. The model achieved an accuracy rate of 100% and a sensitivity rate of 96% for important results. In addition, it achieved a 96% accuracy rate and a sensitivity rate of 100% for minor outcomes. The SHapley Additive exPlanations (SHAP) study found factors, including drowsiness/lethargy, age, ataxia, abdominal pain, and electrolyte abnormalities, significantly influenced individual predictions. The random forest algorithm achieved a 98% accuracy rate in predicting medical outcomes for patients with acute lithium intoxication. The model demonstrated high sensitivity and precision in accurately predicting significant and minor outcomes. Further investigation is necessary to authenticate these findings.

Lithium-induced apoptotic cell death is not accompanied by a noticeable inflammatory response in the kidney

Lithium (Li+) therapy is a valuable tool in psychiatric practice that remains underutilized due to safety concerns. Excessive plasma Li+ levels are nephrotoxic and can trigger a local immune response. Our understanding of the immunomodulatory effects of Li+ in the kidney is fragmentary. Here, we studied how immune mechanisms contribute to the development of Li+-induced adverse effects in the kidneys of C57BL/6NJ mice placed on a 0.3% lithium carbonate diet for 28 days. We combined histochemical techniques, immunoblotting, flow cytometry, qPCR and proteome profiler arrays to characterize renal tissue damage, infiltrating immune cells and cytokine markers, activation of pyroptotic and apoptotic cascades in the kidneys of mice receiving Li+-containing and regular diets. We found that biomarkers of tubular damage, kidney injury marker, KIM-1, and neutrophil gelatinase-associated lipocalin, NGAL, were elevated in the renal tissue of Li+-treated mice when compared to controls. This correlated with increased interstitial fibrosis in Li+-treated mice. Administration of Li+ did not activate the pro-inflammatory NLRP3 inflammasome cascade but promoted apoptosis in the renal tissue. The TUNEL-positive signal and levels of pro-apoptotic proteins, Bax, cleaved caspase-3, and caspase-8, were elevated in the kidneys of Li+-treated mice. We observed a significantly higher abundance of CD93, CCL21, and fractalkine, accumulation of F4.80+ macrophages with reduced M1/M2 polarization ratio and decreased CD4+ levels in the renal tissue of Li+-treated mice when compared to controls. Therefore, after 28 days of treatment, Li+-induced insult to the kidney manifests in facilitated apoptotic cell death without an evident pro-inflammatory response.

External Evaluation of Population Pharmacokinetics Models of Lithium in the Bipolar Population

Lithium has been used in the treatment of bipolar disorder for several decades. Treatment optimization is recommended for this drug, due to its narrow therapeutic range and a large pharmacokinetics (PK) variability. In addition to therapeutic drug monitoring, attempts have been made to predict individual lithium doses using population pharmacokinetics (popPK) models. This study aims to assess the clinical applicability of published lithium popPK models by testing their predictive performance on two different external datasets. Available PopPK models were identified and their predictive performance was determined using a clinical dataset (46 patients/samples) and the literature dataset (89 patients/samples). The median prediction error (PE) and median absolute PE were used to assess bias and inaccuracy. The potential factors influencing model predictability were also investigated, and the results of both external evaluations compared. Only one model met the acceptability criteria for both datasets. Overall, there was a lack of predictability of models; median PE and median absolute PE, respectively, ranged from -6.6% to 111.2% and from 24.4% to 111.2% for the literature dataset, and from -4.5% to 137.6% and from 24.9% to 137.6% for the clinical dataset. Most models underpredicted the observed concentrations (7 out of 10 models presented a negative bias). Renal status was included as a covariate of lithium's clearance in only two models. To conclude, most of lithium's PopPK models had limited predictive performances related to the absence of covariates of interest included, such as renal status. A solution to this problem could be to improve the models with methodologies such as metamodeling. This could be useful in the perspective of model-informed precision dosing.

A Case of Lithium Encephalopathy with Therapeutic Lithium Levels: The Diagnostic Role of EEG

Introduction. Lithium is considered a first-line therapy for both the acute phase and the maintenance of bipolar disorder. Many studies highlighted its neuroprotective and neuroplastic capacity suggesting a potential usefulness in the treatment of neurodegenerative diseases. Despite the undeniable efficacy, lithium clearly presents several adverse effects including neurotoxicity, also known as lithium encephalopathy, regarding both neurological, psychiatric, and cognitive side effects. In this case, adverse reactions are not always related to its serum levels, possibly appearing within the therapeutic range. Case Presentation. We analyzed the case of a bipolar patient who has been uncontinuosly treated with lithium salts since the onset of the psychopathological picture. Over the years, the average values of lithemia always remained around 0.60-0.70 mEq/L, but in 2019, the patient begun to manifest distal tremors and in the mandibular district accompanied, in the following months, by psychomotor slowdown, generalized tremors, reduced alertness, spatiotemporal disorientation, and aphasia. While alterations referable to neurodegenerative diseases were excluded, EEG maintained rhythm alteration 1 year after the probable intoxication. Discussion. This case confirms the central role of EEG for lithium neurotoxicity, while its dosages are in therapeutic range, being plasma levels are not always indicative of liquoral and neuronal lithium's levels. We highlight the importance of an early diagnosis of lithium encephalopathy proposing EEG as an indispensable tool for assessing lithium neurotoxicity both in acute and chronic intoxication.

Clinical evaluation of switching from immediate-release to prolonged-release lithium in bipolar patients, poorly tolerant to lithium immediate-release treatment: A randomized clinical trial

AIM

The effect of switching from lithium immediate release (Li-IR) to lithium prolonged release (Li-PR) on lithium-induced tremor after 1 and 12 weeks of treatment was evaluated in a randomized, multicenter, open trial, in bipolar patients from the participating sites with a tremor severity ≥2 (Udvalg for Kliniske Undersøgelser [UKU] rating scale) despite optimal lithium titration.

METHODS

The primary endpoint was the evaluation of tremor by means of the UKU scale after 1 week of treatment. Secondary endpoints included manic Young Mania Rating Scale (YMRS) and depressive symptoms (Montgomery-Asberg Depression Rating Scale), a global assessment of the patient's status (Clinical Global Impression), polyuria/polydipsia (UKU item 3.8) and patient-reported outcomes.

RESULTS

Owing to difficulties in including suitable patients the enrollment phase was closed when 73 patients were randomized. Notwithstanding the lower number of patients, in the modified intention-to-treat population (n = 70) the primary endpoint was statistically significant: tremor improved after 1 week in 62.9% in Li-PR group against 20.0% of patients in Li-IR group (p = .0006; two-tailed Fisher's exact test). The difference remained statistically significant after 4 (p = .0031) and 12 weeks (p = .0128). The same analysis performed in the PP population confirmed these results. Among the secondary endpoints, only the factor convenience of the treatment satisfaction questionnaire showed a statistically significant difference between groups. There were no apparent differences in the safety profile of the two formulations.

CONCLUSIONS

This study is the first comparative documentation of a potential benefit of the prolonged-release formulation in reducing the symptom tremor, a well-known adverse effect of lithium therapy. Indeed, the study results should be interpreted taking into account the sample size lower than planned.

Clinical response and metabolic effects of lithium in 323 mood disorder patients

BACKGROUND

Lithium is the mainstay for the maintenance treatment of mood disorders (MD), but its efficacy needs to be weighed against its side effects profile. Here, we assessed retrospectively the clinical response to long-term lithium treatment, as well as the rate of associated metabolic side effects.

METHODS

Clinical data were collected from patients treated with lithium for at least 12 months at the Lucio Bini Center for Mood Disorders in Cagliari, Italy. Clinical response was determined as the difference in number of mood episodes and percent of illness time before and during lithium treatment. Symptomatic values of metabolic parameters (plasma levels of glucose, cholesterol, urea nitrogen [BUN], creatinine, TSH, white blood cells [WBC]), and Body Mass Index (BMI) were determined.

RESULTS

We studied 323 MD patients (60.2% women). The percent of illness time was significantly reduced for both depressive (F = 4.94, p<0.0001), and manic (F = 3.95, p < 0.0001) episodes, whereas the rates of episodes/year were significantly reduced for mania (F = 2.01, p = 0.02), but not for depression (F = 1.54, p = 0.06). Rates of MD patients with symptomatic values of metabolic parameters were 14.3% for WBC ≥10,000/µl, 26.9% for glucose levels ≥100 mg/dl, 54.2% for cholesterol levels ≥200 mg/dl, 7.5% for BUN ≥50 mg/dl, 21.9% for creatinine levels ≥1.2 mg/dl, and 20.9% for TSH levels ≥3.50 mU/l.

CONCLUSIONS

Long-term lithium treatment was clinically effective, but the rates of metabolic effects were substantial although some of them were also associated with older age. Lithium-treated patients should receive accurate clinical monitoring to decrease the impact of long-term side effects.

Structural variation in the glycogen synthase kinase 3β and brain-derived neurotrophic factor genes in Japanese patients with bipolar disorders

Background

Lithium is the first‐line drug for the treatment of bipolar disorders (BDs); however, not all patients responded. Glycogen synthase kinase (GSK) 3β and brain‐derived neurotrophic factor (BDNF) play a role in the therapeutic action of lithium. Since structural variations were reported in these genes, it is possible that these genomic variations may be involved in the therapeutic responses to lithium.

Method

Fifty patients with BDs and 50 healthy subjects (mean age 55.0 ± 15.0 years; M/F 19/31) participated. We examined structural variation of the GSK3β and BDNF genes by real‐time PCR. We examined the influence of structural variation of these genes on the therapeutic responses to lithium and the occurrence of antidepressant‐emergent affective switch (AEAS). The efficacy of lithium was assessed using the Alda scale, and AEAS was evaluated using Young Mania Rating Scale.

Results

Although we examined structural variations within intron II and VII of the GSK3^® gene and from the end of exon IV to intron IV and within exon IX of the BDNF gene, no structural variation was found in BDs. Whereas 5 of 50 patients exhibited three copies of the genomic region within exon IV of the BDNF gene, all healthy subjects had two copies. No difference in the therapeutic efficacy of lithium was found between patients with three and two copies. No difference in the occurrence of AEAS was found between the two groups.

Conclusion

The amplification of the BDNF gene influenced neither the therapeutic responses to lithium nor the occurrence of AEAS.

Five of 50 patients with bipolar disorders exhibited three copies of the genomic region within exon IV of the BDNF gene. But, 50 healthy subjects had two copies. This amplification did not affect the therapeutic responses to lithium.

Phycoremediation of lithium ions from aqueous solutions using free and immobilized freshwater green alga Oocystis solitaria: mathematical modeling for bioprocess optimization

Lithium is registered as a serious pollutant that causes environmental damage to an irrigation water supply. Freshwater green alga (Oocystis solitaria) was studied for its potential to remove lithium ions from aqueous solutions. The Plackett-Burman design was applied for initial screening of six factors for their significances for the removal of lithium from aqueous solutions using Oocystis solitaria cells. Among the variables screened, pH, lithium concentration, and temperature were the most significant factors affecting lithium removal. Hence, the levels of these significant variables were further investigated for their interaction effects on lithium removal using the Box-Behnken statistical design. The optimum conditions for maximum lithium removal from aqueous solutions by Oocystis solitaria were the initial lithium concentration of 200 mg/L, contact time of 60 min, temperature of 30 °C, pH 5, and biomass of Oocystis solitaria cells of 1 g/L with agitation condition. Under the optimized conditions, the percentage of maximum lithium removal was 99.95% which is larger than the percentage of lithium removal recorded before applying the Plackett-Burman design (40.07%) by 2.49 times. The different properties of Oocystis solitaria, as an adsorbent, were explored with SEM and via FTIR analysis. The spectrum of FTIR analysis for samples of Oocystis solitaria cells before lithium biosorption showed different absorption peaks at 3394 cm^-1, 2068 cm^-1, 1638 cm^-1, 1398 cm^-1, 1071 cm^-1, and 649 cm^-1 which has been shifted to 3446 cm^-1, 2924 cm^-1, 1638 cm^-1, 1384 cm^-1, 1032 cm^-1, and 613 cm^-1, respectively, after lithium biosorption by the alga. The treatment of aqueous solution containing lithium with Oocystis solitaria cells immobilized in alginate beads removed 98.71% of lithium at an initial concentration of 200 mg/L after 5 h. Therefore, Oocystis solitaria may be considered as an alternative for sorption and removal of lithium ions from wastewaters.

Population Pharmacokinetics and Exposure-Response of Lithium Carbonate in Patients Based on Tubular Reabsorption Mechanisms

BACKGROUND AND OBJECTIVE

Lithium, which is used to treat bipolar disorder, has a narrow therapeutic blood concentration range and quickly reaches clinically toxic levels. We performed a population pharmacokinetic analysis with a lithium tubular reabsorption model including urinary pH and investigated the relationship between blood lithium concentration and tremor as a side effect.

METHODS

Routine clinical data, including 389 serum concentrations, were collected from 214 patients orally administered an adjusted amount of lithium carbonate. Pharmacokinetics were described using a one-compartment distribution model with first-order absorption and elimination. The fractions of the MID (Li⁺ + LiCO₃^-) and ION (2Li⁺ + CO₃^2-) forms were calculated using the Henderson-Hasselbalch equation, and the influences of these fractions on clearance (CL) were evaluated. The rate of tremor development was analyzed using a logit model.

RESULTS

Oral apparent CL (CL/F) was explained by nonrenal CL and renal CL, and renal CL was varied by the fractions of lithium forms influenced by urinary pH. The contribution of MID to CL was slightly larger than that of ION. The rate of tremor development was estimated to be more than 30% when the trough lithium concentration was greater than 1.26 mEq L^-1.

CONCLUSION

Renal function and urinary pH are important indices in lithium treatment, so the serum concentration of lithium may be predicted based on the renal function and urinary pH.

An Oldie but Goodie: Lithium in the Treatment of Bipolar Disorder through Neuroprotective and Neurotrophic Mechanisms

Lithium has been used for the treatment of bipolar disorder (BD) for the last sixty or more years, and recent studies with more reliable designs and updated guidelines have recommended lithium to be the treatment of choice for acute manic, mixed and depressive episodes of BD, along with long-term prophylaxis. Lithium’s specific mechanism of action in mood regulation is progressively being clarified, such as the direct inhibition on glycogen synthase kinase 3β, and its various effects on neurotrophic factors, neurotransmitters, oxidative metabolism, apoptosis, second messenger systems, and biological systems are also being revealed. Furthermore, lithium has been proposed to exert its treatment effects through mechanisms associated with neuronal plasticity. In this review, we have overviewed the clinical aspects of lithium use for BD, and have focused on the neuroprotective and neurotrophic effects of lithium.

Correlation of lithium bioaccessibility from tea (Camellia sinensis L.) with tea type and consumption habits

In this study, the total contents, leachability into tea infusions, and bioaccessibility of lithium from black, Earl Grey, and green teas were evaluated by inductively coupled plasma mass spectrometry. Leachabilities were evaluated after infusion for 2, 5, or 10min. Bioaccessibility was determined in vitro under simulated stomach and intestinal digestion conditions. Addition of lemon juice, sugar, or milk for consumption, and calcium, tannic acid, and citric acid as additives were evaluated to determine if they affected bioaccessibility of lithium from black tea. The bioaccessible lithium contributed to 0.01%, 0.02%, and 0.03% of the recommended dietary allowances of lithium for black, Earl Grey, and green tea samples, respectively. These contributions may increase up to 4.4 times or decrease up to seven times with certain additives.

Does the "Silver Bullet" Lose its Shine Over the Time? Assessment of Loss of Lithium Response in a Preliminary Sample of Bipolar Disorder Outpatients

Background:

Though often perceived as a “silver bullet” treatment for bipolar disorder (BD), lithium has seldom reported to lose its efficacy over the time.

Objective:

The aim of the present study was to assess cases of refractoriness toward restarted lithium in BD patients who failed to preserve maintenance.

Method:

Treatment trajectories associated with re-instituted lithium following loss of achieved lithium-based maintenance in BD were retrospectively reviewed for 37 BD-I patients (median age 52 years; F:M=17:20 or 46% of the total) over an 8.1-month period on average.

Results:

In our sample only 4 cases (roughly 11% of the total, of whom F:M=2:2) developed refractoriness towards lithium after its discontinuation. Thirty-three controls (F:M=15:18) maintained lithium response at the time of re-institution. No statistically significant difference between cases and controls was observed with respect to a number of demographic and clinical features but for time spent before first trial ever with lithium in life (8.5 vs. 3 years; U=24.5, Z=-2.048, p=.041) and length of lithium discontinuation until new therapeutic attempt (5.5 vs. 2 years; U=8, Z=-2.927, p=.003) between cases vs. controls respectively. Tapering off of lithium was significantly faster among cases vs. controls (1 vs. 7 days; U=22, Z=-2.187), though both subgroups had worrisome high rates of poor adherence overall.

Conclusion:

Although intrinsic limitations of the present preliminary assessment hamper the validity and generalizability of overall results, stating the clinical relevance of the topic further prospective research is warranted. The eventual occurrence of lithium refractoriness may indeed be associated with peculiar course trajectories and therapeutic outcomes ultimately urging the prescribing clinicians to put efforts in preserving maintenance of BD in the absence of any conclusive research insight on the matter.

Lithium in Bipolar Disorder: Optimizing Therapy Using Prolonged-Release Formulations

Lithium has been a gold standard in the treatment of bipolar disorder (BD) for several decades. Despite a general reduction in the use of lithium over the past several years, it is effective in the management of both manic and depressive episodes in BD and continues to be recommended as a first-line mood stabilizer. This review provides an overview of the pharmacology of lithium and highlights its clinical profile in the management of BD, focusing on the potential advantages of prolonged-release (PR) versus immediate-release (IR) formulations of lithium. A literature search using PubMed was performed to identify articles describing IR and PR lithium in BD using specific search terms like 'lithium', 'prolonged-release', 'sustained-release', 'extended-release', 'bipolar disorder', 'adherence' and 'compliance'. Relevant pharmacodynamic and pharmacokinetic data were also included. Several clinical trials suggested that lithium is effective in the treatment of acute mania and prophylaxis of BD and reduces the risk of suicide in patients with BD; it may also be used in combination with other drugs in the treatment of bipolar depression. Treatment with lithium must be monitored to avoid lithium-associated toxicity. The prolonged PR formulation of lithium has several advantages including consistent serum lithium concentrations, fewer adverse events and improved adherence to therapy. Although direct comparative studies between PR and IR formulations of lithium are primarily limited to pharmacokinetic studies, PR formulation of lithium provides potential advantages over IR formulation and can be effectively used in the management of BD with lesser adverse events.

Exposure to lithium through drinking water and calcium homeostasis during pregnancy: A longitudinal study

There is increasing evidence of adverse health effects due to elevated lithium exposure through drinking water but the impact on calcium homeostasis is unknown. This study aimed at elucidating if lithium exposure through drinking water during pregnancy may impair the maternal calcium homeostasis. In a population-based mother-child cohort in the Argentinean Andes (n=178), with elevated lithium concentrations in the drinking water (5-1660μg/L), blood lithium concentrations (correlating significantly with lithium in water, urine and plasma) were measured repeatedly during pregnancy by inductively coupled plasma mass spectrometry and used as exposure biomarker. Markers of calcium homeostasis included: plasma 25-hydroxyvitamin D3, serum parathyroid hormone (PTH), and calcium, phosphorus and magnesium concentrations in serum and urine. The median maternal blood lithium concentration was 25μg/L (range 1.9-145). In multivariable-adjusted mixed-effects linear regression models, blood lithium was inversely associated with 25-hydroxyvitamin D3 (-6.1nmol/L [95%CI -9.5; -2.6] for a 25μg/L increment in blood lithium). The estimate increased markedly with increasing percentiles of 25-hydroxyvitamin D3. In multivariable-adjusted mixed-effects logistic regression models, the odds ratio of having 25-hydroxyvitamin D3<30nmol/L (19% of the women) was 4.6 (95%CI 1.1; 19.3) for a 25μg/L increment in blood lithium. Blood lithium was also positively associated with serum magnesium, but not with serum calcium and PTH, and inversely associated with urinary calcium and magnesium. In conclusion, our study suggests that lithium exposure through drinking water during pregnancy may impair the calcium homeostasis, particularly vitamin D. The results reinforce the need for better control of lithium in drinking water, including bottled water.

Exposure to Lithium and Cesium Through Drinking Water and Thyroid Function During Pregnancy: A Prospective Cohort Study

BACKGROUND

Impaired thyroid function is a common side effect of lithium medication. Recent data indicate that lithium exposure through drinking water, although providing much lower doses than the medication, may also affect thyroid hormone levels. However, the effects in susceptible groups like pregnant women are not known.

METHODS

In a population-based mother-child cohort in the Argentinean Andes (n = 194), an area with varying concentrations of lithium in the drinking water, we assessed lithium exposure repeatedly during pregnancy by measuring the concentrations in blood using inductively coupled plasma mass spectrometry. The markers of thyroid function included thyrotropin (TSH), free/total thyroxine (fT4/T4), free/total triiodothyronine (fT3/T3), thyroglobulin, and transthyretin in serum, sampled at the same time. Multiple potential confounders, including exposure to arsenic, cesium, and boron (elevated in water) as well as selenium and iodine (essential for thyroid function) were considered.

RESULTS

The lithium concentrations in blood [median 25 μg/L (0.0036 mmol/L); range 1.9-145 μg/L (0.000027-0.021 mmol/L)] correlated significantly with those in urine and drinking water (rs = 0.84, p < 0.001, and rs = 0.40, p < 0.001, respectively). Using linear quantile regression models, we found a positive association between blood lithium (log2 transformed) and TSH concentrations, particularly in the lowest percentiles of TSH (B = 0.20 mIU/L, [95% confidence interval 0.048-0.35] at the fifth percentile). We also found inverse associations of blood lithium with transthyretin, particularly at the highest percentiles, as well as with fT3 and T3, with less obvious variation across percentiles. Unexpectedly, blood cesium concentrations (median 111 μg/L, range 2.5-711 μg/L) were also inversely associated with fT3 and T3, particularly at the highest T3 percentiles, but not with TSH or transthyretin. Arsenic and boron exposure (also through drinking water) did not show any associations with the thyroid parameters.

CONCLUSIONS

The study supports previous findings that lithium exposure through drinking water may impair thyroid function. The results regarding cesium exposure through drinking water are new. During pregnancy, impaired thyroid function may be detrimental for fetal development. The findings reinforce the need for better control of drinking water, including bottled water, as well as a health-based guideline value.

Environmental exposure to lithium during pregnancy and fetal size: a longitudinal study in the Argentinean Andes

BACKGROUND

Lithium, used for treating bipolar disease, crosses freely the placenta and is classified as teratogenic. It is unclear to what extent environmental lithium exposure may affect fetal growth and development.

OBJECTIVES

To elucidate potential effects of lithium exposure through drinking water during pregnancy on fetal size.

METHODS

We developed a prospective population-based mother-child cohort (N=194) in an area with highly varying drinking water lithium concentrations (5-1600 μg/L) in northern Argentinean Andes. Blood and urinary lithium concentrations (sampled repeatedly during pregnancy) were measured using inductively coupled plasma mass spectrometry. We measured fetal size by ultrasound in second and third trimesters, and weight, length and head circumference at birth. Multivariable models were used to examine associations between lithium exposure (continuous and in tertiles) and fetal size measures.

RESULTS

Lithium in maternal blood (median 25; range 1.9-145 μg/L) and urine (1645; 105-4600 μg/L) was inversely associated (apparently linearly) with all fetal measures (body, head and femur) in the second trimester, and with birth length (β -0.53 cm per 25 μg/L increase in blood lithium, 95%CI -1.0; -0.052). An increase of 100 μg/L in blood was associated with 2 cm shorter newborns (about one standard deviation).

CONCLUSIONS

Lithium exposure through drinking water was associated with impaired fetal size and this seemed to be initiated in early gestation. Further studies are warranted to confirm causality and to understand the mechanisms. If confirmed, these findings have public health relevance and emphasize the need for more data on lithium concentrations in drinking water, including bottled water.

How appropriate is therapeutic drug monitoring for lithium? Data from the Belgian external quality assessment scheme

BACKGROUND

Lithium remains a mainstay in the management of mood disorders. As with many psychotropic drugs, lithium treatment requires continuous observation for adverse effects and strict monitoring of serum concentrations. The present study aimed to assess the appropriateness of lithium assays used by Belgian laboratories, and to evaluate acceptability of their clinical interpretations.

METHODS

Nine in-house serum samples spiked with predetermined concentrations of lithium were distributed to 114 participants in the Belgian external quality assessment scheme. Laboratories were requested to report the assay technique, lithium measurements and interpretations with regard to measured concentrations. Inter/intramethod imprecision and bias were reported and acceptability of clinical interpretations was assessed. The intramethod variability was evaluated by selecting methods used by 6 laboratories or more. Flame photometry (IL 943) was considered as the reference method.

RESULTS

Laboratories returned assay results using colorimetry (69.3%), ion selective electrode (15.8%), flame photometry (8.8%), atomic absorption spectroscopy (5.2%) or mass spectrometry (0.9%). Lithium concentrations were systematically higher when measured with the Vitros assay (median bias: 4.0%), and were associated with consecutive biased interpretations. In contrast, the Thermo Scientific Infinity assay showed a significant negative bias (median bias: 9.4%). 36.0% of laboratories reported numerical values below their manufacturer cut-off for the blank sample; 16.6% of these laboratories detected residual lithium concentrations.

CONCLUSIONS

The present study revealed assay-related differences in lithium measurements and their interpretations. Overall, there appeared to be a need to continue EQA of therapeutic drug monitoring for lithium in Belgium.

Long term course of bipolar I disorder in India: using retrospective life chart method

BACKGROUND

There are grounds to believe that the course of bipolar disorder may be different in tropical countries such as India when compared to temperate nations. There is a dearth of literature about the course of bipolar I disorder from India.

METHODS

This study was conducted in a multispecialty teaching hospital in southern India. Patients with a DSM-IV TR diagnosis of bipolar I disorder, confirmed using SCID-I, with a minimum duration of illness of 3 years were assessed. Information was gathered on demographic and clinical variables, and the life course of episodes was charted using the National Institute of Mental Health - Life Chart Methodology Clinician Retrospective Chart (NIMH-LCM-CRC).

RESULTS

A total of 150 patients with bipolar disorder were included. The mean age at onset of illness was 24.8 (± 8.2) years. Mania was the first episode in a majority (85%) of the cases, and was the most frequent episode in the course of the illness, followed by depression. Patients spent an average of 11.1% of the illness duration in a mood episode, most commonly a manic episode. The median duration of manic or depressive episode was 2 months. Median time to recurrence after the first episode was 21 months (inter-quartile range of 10-60 months), and was shorter for women than men.

LIMITATIONS

The hospital based sample from a particular region limits generalizability. Recall bias may be present in this retrospective information based study. Medical illness, personality disorders, other Axis I psychiatric disorders (apart from substance use disorder) and influence of adherence to treatment on the course of the disorder were not assessed systematically.

CONCLUSIONS

Bipolar I disorder among Indian patients has a course characterized by predominantly manic episodes, which is in line with previous reports from tropical countries and substantially different from that of temperate regions.

Minimizing negative outcomes associated with potentially harmful lithium levels by means of pharmacist-led educational interventions in an inpatient psychiatric facility

Introduction: Studies examining educational interventions led by pharmacists to minimize negative outcomes associated with elevated and potentially harmful lithium levels in inpatient psychiatric facilities are lacking. Other studies indicate a need for improvement of therapeutic drug monitoring for lithium. The aim of this article is to identify potential improvements in negative outcomes associated with harmful lithium blood levels after educational interventions are delivered by a clinical pharmacist to providers of an inpatient psychiatric facility.

Methods: Medication reports were queried from the pharmacy database to identify all patients who were taking lithium within 1 year. Laboratory results, physician progress notes, nursing progress notes, and treatment plans were studied to detect any adverse events associated with lithium levels. Educational interventions created by pharmacy services were tailored toward medical staff and delivered over a 3 month period. Learning was assessed at pre-educational and posteducational interventions.

Results: One hundred fifteen patients received lithium between March 2012 and March 2013. The most-frequent adverse effects reported associated with lithium included tremor, dizziness, slurred speech, and lethargy. Two patients were sent to the local emergency department for lithium toxicity and required dialysis. Fifty-two patients received lithium after educational interventions, and no adverse events were reported. A lithium drug-monitoring spreadsheet was created for pharmacy use, and drug-monitoring guidelines were revised and disseminated throughout the facility.

Discussion: A reduction in negative outcomes associated with lithium was noted after educational interventions to medical staff occurred. The impact of pharmacist-led educational interventions demonstrated a high potential for success.

Outcome of mood stabilizer discontinuation in bipolar disorder after 5 years of euthymia

OBJECTIVE

The objective was to study the outcome of mood stabilizer discontinuation on recurrence in patients with bipolar disorder after at least 5 years of euthymia.

METHODS

Twenty-three patients diagnosed with bipolar affective disorder according to the International Classification of Diseases, 10th Revision Diagnostic Criteria for Research, receiving mood stabilizer prophylaxis for at least 5 years, had undergone planned discontinuation, and the rates and time to recurrence were studied.

RESULTS

Twenty (87%) of 23 patients had recurrence, and all of the episodes were manic. Kaplan-Meier survival analysis showed median time to recurrence following discontinuation of mood stabilizer prophylaxis was 10 months (SE, 6.06 months; 95% confidence interval, 0 to 21.89 months).

CONCLUSION

Four fifths of our patients had recurrence following discontinuation of mood stabilizer prophylaxis within 10 months.

An important role for cholecystokinin, a CLOCK target gene, in the development and treatment of manic-like behaviors

Mice with a mutation in the Clock gene (ClockΔ19) have been identified as a model of mania; however, the mechanisms that underlie this phenotype, and the changes in the brain that are necessary for lithium's effectiveness on these mice remain unclear. Here, we find that cholecystokinin (Cck) is a direct transcriptional target of CLOCK and levels of Cck are reduced in the ventral tegmental area (VTA) of ClockΔ19 mice. Selective knockdown of Cck expression via RNA interference in the VTA of wild-type mice produces a manic-like phenotype. Moreover, chronic treatment with lithium restores Cck expression to near wild-type and this increase is necessary for the therapeutic actions of lithium. The decrease in Cck expression in the ClockΔ19 mice appears to be due to a lack of interaction with the histone methyltransferase, MLL1, resulting in decreased histone H3K4me3 and gene transcription, an effect reversed by lithium. Human postmortem tissue from bipolar subjects reveals a similar increase in Cck expression in the VTA with mood stabilizer treatment. These studies identify a key role for Cck in the development and treatment of mania, and describe some of the molecular mechanisms by which lithium may act as an effective antimanic agent.

Maintenance treatment with quetiapine when combined with either lithium or divalproex in bipolar I disorder: analysis of two large randomized, placebo-controlled trials

BACKGROUND

To determine the efficacy and safety of quetiapine combined with lithium or divalproex for preventing mood events in patients with bipolar I disorder. In this pooled analysis of two similar long-term studies (D1447C00126 [NCT00107731] and D1447C00127 [NCT00081380]), lithium and divalproex treatment groups were analyzed separately.

METHODS

Patients received open-label quetiapine (400-800 mg/d) plus lithium or divalproex to achieve ≥12 weeks of clinical stability before being randomized to double-blind combination treatment with quetiapine (400-800 mg/d) or placebo plus lithium or divalproex for up to 104 weeks. The primary endpoint was time to first mood event postrandomization following open stabilization.

RESULTS

Of 3,414 patients in the stabilization phase, 1,326 were randomized. There were no differences in the risk of recurrence of mood, mania, or depression between quetiapine plus lithium or quetiapine plus divalproex. Among patients co-treated with placebo and lithium, the risk of recurrence of a mania event was significantly higher than among patients co-treated with placebo and divalproex. In patients with an index episode of mania, placebo plus lithium was associated with a significantly higher risk of recurrence of a mania event than placebo plus divalproex. Safety data were generally consistent with recognized safety profiles.

CONCLUSIONS

In patients with bipolar I disorder previously stabilized on quetiapine and lithium or divalproex, maintenance therapy with quetiapine significantly increased the time to recurrence of a mood event (mania or depression) versus placebo, regardless of whether it was combined with lithium or divalproex.

Maternal exposure to metals--concentrations and predictors of exposure

A variety of metals are important for biological function but have also been shown to impact health at elevated concentrations, whereas others have no known biological function. Pregnant women are a vulnerable population and measures to reduce exposure in this group are important. We undertook a study of maternal exposure to the metals, aluminium, arsenic, copper, cobalt, chromium, lithium, manganese, nickel, selenium, tin, uranium and zinc in 173 participants across Western Australia. Each participant provided a whole blood and urine sample, as well as drinking water, residential soil and dust samples and completed a questionnaire. In general the concentrations of metals in all samples were low with the notable exception of uranium (blood U mean 0.07 µg/L, range <0.01-0.25 µg/L; urinary U mean 0.018 µg/g creatinine, range <0.01-0.199 µg/g creatinine). Factors that influenced biological concentrations were consumption of fish which increased urinary arsenic concentrations, hobbies (including mechanics and welding) which increased blood manganese concentrations and iron/folic acid supplement use which was associated with decreased concentrations of aluminium and nickel in urine and manganese in blood. Environmental concentrations of aluminium, copper and lithium were found to influence biological concentrations, but this was not the case for other environmental metals concentrations. Further work is underway to explore the influence of diet on biological metals concentrations in more detail. The high concentrations of uranium require further investigation.

Lithium alters the morphology of neurites regenerating from cultured adult spiral ganglion neurons

The small-molecule drug lithium (as a monovalent ion) promotes neurite regeneration and functional recovery, is easy to administer, and is approved for human use to treat bipolar disorder. Lithium exerts its neuritogenic effect mainly by inhibiting glycogen synthase kinase 3, a constitutively-active serine/threonine kinase that is regulated by neurotrophin and "wingless-related MMTV integration site" (Wnt) signaling. In spiral ganglion neurons of the cochlea, the effects of lithium and the function of glycogen synthase kinase 3 have not been investigated. We, therefore, set out to test whether lithium modulates neuritogenesis from adult spiral ganglion neurons. Primary cultures of dissociated spiral ganglion neurons from adult mice were exposed to lithium at concentrations between 0 and 12.5 mM. The resulting neurite morphology and growth-cone appearance were measured in detail by using immunofluorescence microscopy and image analysis. We found that lithium altered the morphology of regenerating neurites and their growth cones in a differential, concentration-dependent fashion. Low concentrations of 0.5-2.5 mM (around the half-maximal inhibitory concentration for glycogen synthase kinase 3 and the recommended therapeutic serum concentration for bipolar disorder) enhanced neurite sprouting and branching. A high concentration of 12.5 mM, in contrast, slowed elongation. As the lithium concentration rose from low to high, the microtubules became increasingly disarranged and the growth cones more arborized. Our results demonstrate that lithium selectively stimulates phases of neuritogenesis that are driven by microtubule reorganization. In contrast, most other drugs that have previously been tested on spiral ganglion neurons are reported to inhibit neurite outgrowth or affect only elongation. Lithium sensitivity is a necessary, but not sufficient condition for the involvement of glycogen synthase kinase 3. Our results are, therefore, consistent with, but do not prove lithium inhibiting glycogen synthase kinase 3 activity in spiral ganglion neurons. Experiments with additional drugs and molecular-genetic tools will be necessary to test whether glycogen synthase kinase 3 regulates neurite regeneration from spiral ganglion neurons, possibly by integrating neurotrophin and Wnt signals at the growth cone.

Potential mechanisms of action of lithium in bipolar disorder. Current understanding

Lithium has been used for over half a century for the treatment of bipolar disorder as the archetypal mood stabilizer, and has a wealth of empirical evidence supporting its efficacy in this role. Despite this, the specific mechanisms by which lithium exerts its mood-stabilizing effects are not well understood. Given the inherently complex nature of the pathophysiology of bipolar disorder, this paper aims to capture what is known about the actions of lithium ranging from macroscopic changes in mood, cognition and brain structure, to its effects at the microscopic level on neurotransmission and intracellular and molecular pathways. A comprehensive literature search of databases including MEDLINE, EMBASE and PsycINFO was conducted using relevant keywords and the findings from the literature were then reviewed and synthesized. Numerous studies report that lithium is effective in the treatment of acute mania and for the long-term maintenance of mood and prophylaxis; in comparison, evidence for its efficacy in depression is modest. However, lithium possesses unique anti-suicidal properties that set it apart from other agents. With respect to cognition, studies suggest that lithium may reduce cognitive decline in patients; however, these findings require further investigation using both neuropsychological and functional neuroimaging probes. Interestingly, lithium appears to preserve or increase the volume of brain structures involved in emotional regulation such as the prefrontal cortex, hippocampus and amygdala, possibly reflecting its neuroprotective effects. At a neuronal level, lithium reduces excitatory (dopamine and glutamate) but increases inhibitory (GABA) neurotransmission; however, these broad effects are underpinned by complex neurotransmitter systems that strive to achieve homeostasis by way of compensatory changes. For example, at an intracellular and molecular level, lithium targets second-messenger systems that further modulate neurotransmission. For instance, the effects of lithium on the adenyl cyclase and phospho-inositide pathways, as well as protein kinase C, may serve to dampen excessive excitatory neurotransmission. In addition to these many putative mechanisms, it has also been proposed that the neuroprotective effects of lithium are key to its therapeutic actions. In this regard, lithium has been shown to reduce the oxidative stress that occurs with multiple episodes of mania and depression. Further, it increases protective proteins such as brain-derived neurotrophic factor and B-cell lymphoma 2, and reduces apoptotic processes through inhibition of glycogen synthase kinase 3 and autophagy. Overall, it is clear that the processes which underpin the therapeutic actions of lithium are sophisticated and most likely inter-related.

Environmental lithium exposure in the north of Chile--II. Natural food sources

Lithium, generally, occurs in barely trace amounts in ground water with few major exceptions. One of these is the northern area of Chile where all potable water and many of the food stuffs contain high levels of lithium. Surface water can contain between 100 and 10,000 times more than most rivers in North America. Inevitably, food, both animal and vegetable, contains higher lithium levels than found elsewhere. In consequence, the local population has been exposed to high levels of lithium in their food and drinking water for as long as the region has been populated. The present report details lithium levels in a variety of food stuffs from several locations in Northern Chile and compares these with those found elsewhere. The implications for the local population have been discussed in our earlier paper.

Early improvement of psychotic symptoms with lithium monotherapy as a predictor of later response in mania

Although lithium has been the first line agent in the treatment of bipolar disorder (BD), few studies have evaluated lithium's efficacy in mania with psychosis and its association with later response. Furthermore, given the widespread concern about antipsychotic side effects, answering a question about whether lithium alone can manage to treat both psychotic and non-psychotic mania seems a very relevant one. The present study addresses the antipsychotic efficacy of lithium monotherapy in acute mania and early improvement of psychotic symptoms as a predictor of later response of manic symptoms. Forty-six patients presenting a manic episode (32 with psychotic features and 14 subjects without psychotic features) were treated for 4 weeks with lithium monotherapy and evaluated weekly using the Young Mania Rating Scale (YMRS). Subjects with rapid cycling, substance abuse/dependence, or mixed episodes were excluded. The overall antimanic efficacy of lithium in psychosis vs. non-psychosis groups was evaluated. In addition, early improvement of psychotic symptoms and its prediction of subsequent response (>50% decrease in total YMRS scores) or remission were evaluated. Lithium showed a similar efficacy in both psychosis and non-psychosis mania. Early improvement of psychotic symptoms was associated with clinical response and remission at endpoint.

Relationship between serum lithium, salivary lithium, and urinary lithium in patients on lithium therapy

Lithium carbonate is used in the treatment of both psychiatric and nonpsychiatric disorders. The aim of this study was to explore the relationship between serum lithium, salivary lithium, and urinary lithium. Blood, saliva, and urine samples were collected from 50 patients, and estimation of serum, salivary, and urine lithium was done using an atomic absorption spectrophotometer. Mean serum lithium was 0.75 ± 0.25 mEq/L, mean salivary lithium was 1.91 ± 0.80 mEq/L, and mean urine lithium was 7.16 ± 4.84 mEq/L. A significant direct correlation was found between serum lithium and salivary lithium (r = 0.695, p < 0.001). This correlation was higher in females (r = 0.770, p < 0.001) when compared to males (r = 0.665, p < 0.001). Even though a significant correlation was found between serum and salivary lithium levels, more studies are needed in this domain to establish salivary therapeutic monitoring as a feasible option for patients on lithium carbonate therapy.

Predictive animal models of mania: hits, misses and future directions

Mania has long been recognized as aberrant behaviour indicative of mental illness. Manic states include a variety of complex and multifaceted symptoms that challenge clear clinical distinctions. Symptoms include over-activity, hypersexuality, irritability and reduced need for sleep, with cognitive deficits recently linked to functional outcome. Current treatments have arisen through serendipity or from other disorders. Hence, treatments are not efficacious for all patients, and there is an urgent need to develop targeted therapeutics. Part of the drug discovery process is the assessment of therapeutics in animal models. Here we review pharmacological, environmental and genetic manipulations developed to test the efficacy of therapeutics in animal models of mania. The merits of these models are discussed in terms of the manipulation used and the facet of mania measured. Moreover, the predictive validity of these models is discussed in the context of differentiating drugs that succeed or fail to meet criteria as approved mania treatments. The multifaceted symptomatology of mania has not been reflected in the majority of animal models, where locomotor activity remains the primary measure. This approach has resulted in numerous false positives for putative treatments. Recent work highlights the need to utilize multivariate strategies to enable comprehensive assessment of affective and cognitive dysfunction. Advances in therapeutic treatment may depend on novel models developed with an integrated approach that includes: (i) a comprehensive battery of tests for different aspects of mania, (ii) utilization of genetic information to establish aetiological validity and (iii) objective quantification of patient behaviour with translational cross-species paradigms.

The science and practice of lithium therapy

INTRODUCTION

Despite more that 60 years of clinical experience, the effective use of lithium for the treatment of mood disorder, in particular bipolarity, is in danger of becoming obsolete. In part, this is because of exaggerated fears surrounding lithium toxicity, acute and long-term tolerability and the encumbrance of life-long plasma monitoring. Recent research has once again positioned lithium centre stage and amplified the importance of understanding its science and how this translates to clinical practice.

OBJECTIVE

The aim of this paper is to provide a sound knowledge base as regards the science and practice of lithium therapy.

METHOD

A comprehensive literature search using electronic databases was conducted along with a detailed review of articles known to the authors pertaining to the use of lithium. Studies were limited to English publications and those dealing with the management of psychiatric disorders in humans. The literature was synthesized and organized according to relevance to clinical practice and understanding.

RESULTS

Lithium has simple pharmacokinetics that require regular dosing and monitoring. Its mechanisms of action are complex and its effects are multi-faceted, extending beyond mood stability to neuroprotective and anti-suicidal properties. Its use in bipolar disorder is under-appreciated, particularly as it has the best evidence for prophylaxis, qualifying it perhaps as the only true mood stabilizer currently available. In practice, its risks and tolerability are exaggerated and can be readily minimized with knowledge of its clinical profile and judicious application.

CONCLUSION

Lithium is a safe and effective agent that should, whenever indicated, be used first-line for the treatment of bipolar disorder. A better understanding of its science alongside strategic management of its plasma levels will ensure both wider utility and improved outcomes.

[Suicide and nutrition: a bio-psychosocial approach]

This article proposes a new bio-psychosocial perspective on the links between mental health, more specifically suicide, and nutrition. We first discuss the links between nutrition, its social role and suicide. The act of eating is studied as a social integrator and regulator, in the light of Durkheim's theorization. Nutrition is also examined as self-destruction, with particular cases of "diet-related suicide." De-structuring of meals and alienating foods are identified as contributing factors to the de-structuring of "nutrition models." We then discuss the place of food within the psychopathology, and finally, the links between biological parameters reflected in food and suicide risk. Avenues of research and intervention along this bio-psychosocial approach are also proposed.

General and comparative efficacy and effectiveness of antidepressants in the acute treatment of depressive disorders: a report by the WPA section of pharmacopsychiatry

Current gold standard approaches to the treatment of depression include pharmacotherapeutic and psychotherapeutic interventions with social support. Due to current controversies concerning the efficacy of antidepressants in randomized controlled trials, the generalizability of study findings to wider clinical practice and the increasing importance of socioeconomic considerations, it seems timely to address the uncertainty of concerned patients and relatives, and their treating psychiatrists and general practitioners. We therefore discuss both the efficacy and clinical effectiveness of antidepressants in the treatment of depressive disorders. We explain and clarify useful measures for assessing clinically meaningful antidepressant treatment effects and the types of studies that are useful for addressing uncertainties. This includes considerations of methodological issues in randomized controlled studies, meta-analyses, and effectiveness studies. Furthermore, we summarize the differential efficacy and effectiveness of antidepressants with distinct pharmacodynamic properties, and differences between studies using antidepressants and/or psychotherapy. We also address the differential effectiveness of antidepressant drugs with differing modes of action and in varying subtypes of depressive disorder. After highlighting the clinical usefulness of treatment algorithms and the divergent biological, psychological, and clinical efforts to predict the effectiveness of antidepressant treatments, we conclude that the spectrum of different antidepressant treatments has broadened over the last few decades. The efficacy and clinical effectiveness of antidepressants is statistically significant, clinically relevant, and proven repeatedly. Further optimization of treatment can be helped by clearly structured treatment algorithms and the implementation of psychotherapeutic interventions. Modern individualized antidepressant treatment is in most cases a well-tolerated and efficacious approach to minimize the negative impact of otherwise potentially devastating and life-threatening outcomes in depressive disorders.

Specific role of VTA dopamine neuronal firing rates and morphology in the reversal of anxiety-related, but not depression-related behavior in the ClockΔ19 mouse model of mania

Lithium has been used extensively for mood stabilization, and it is particularly efficacious in the treatment of bipolar mania. Like other drugs used in the treatment of psychiatric diseases, it has little effect on the mood of healthy individuals. Our previous studies found that mice with a mutation in the Clock gene (ClockΔ19) have a complete behavioral profile that is very similar to human mania, which can be reversed with chronic lithium treatment. However, the cellular and physiological effects that underlie its targeted therapeutic efficacy remain unknown. Here we find that ClockΔ19 mice have an increase in dopaminergic activity in the ventral tegmental area (VTA), and that lithium treatment selectively reduces the firing rate in the mutant mice with no effect on activity in wild-type mice. Furthermore, lithium treatment reduces nucleus accumbens (NAc) dopamine levels selectively in the mutant mice. The increased dopaminergic activity in the Clock mutants is associated with cell volume changes in dopamine neurons, which are also rescued by lithium treatment. To determine the role of dopaminergic activity and morphological changes in dopamine neurons in manic-like behavior, we manipulated the excitability of these neurons by overexpressing an inwardly rectifying potassium channel subunit (Kir2.1) selectively in the VTA of ClockΔ19 mice and wild-type mice using viral-mediated gene transfer. Introduction of this channel mimics the effects of lithium treatment on the firing rate of dopamine neurons in ClockΔ19 mice and leads to a similar change in dopamine cell volume. Furthermore, reduction of dopaminergic firing rates in ClockΔ19 animals results in a normalization of locomotor- and anxiety-related behavior that is very similar to lithium treatment; however, it is not sufficient to reverse depression-related behavior. These results suggest that abnormalities in dopamine cell firing and associated morphology underlie alterations in anxiety-related behavior in bipolar mania, and that the therapeutic effects of lithium come from a reversal of these abnormal phenotypes.

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.

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.

Lithium ameliorates nucleus accumbens phase-signaling dysfunction in a genetic mouse model of mania

Polymorphisms in circadian genes such as CLOCK convey risk for bipolar disorder. While studies have begun to elucidate the molecular mechanism whereby disruption of Clock alters cellular function within mesolimbic brain regions, little remains known about how these changes alter gross neural circuit function and generate mania-like behaviors in Clock-Δ19 mice. Here we show that the phasic entrainment of nucleus accumbens (NAC) low-gamma (30-55 Hz) oscillations to delta (1-4 Hz) oscillations is negatively correlated with the extent to which wild-type (WT) mice explore a novel environment. Clock-Δ19 mice, which display hyperactivity in the novel environment, exhibit profound deficits in low-gamma and NAC single-neuron phase coupling. We also demonstrate that NAC neurons in Clock-Δ19 mice display complex changes in dendritic morphology and reduced GluR1 expression compared to those observed in WT littermates. Chronic lithium treatment ameliorated several of these neurophysiological deficits and suppressed exploratory drive in the mutants. These results demonstrate that disruptions of Clock gene function are sufficient to promote alterations in NAC microcircuits, and raise the hypothesis that dysfunctional NAC phase signaling may contribute to the mania-like behavioral manifestations that result from diminished circadian gene function.

Acute Bipolar Depression: A Review of the Use of Olanzapine/Fluoxetine

Depression is the predominant mood state in patients with bipolar I or II disorder over the course of illness. In spite of this, relatively few pharmacological treatments have been shown to be effective for treating depressive episodes associated with bipolar disorder in adults. Combination therapy with olanzapine and fluoxetine (OFC) is approved in the US for the treatment of acute depressive episodes in adults with bipolar I disorder. The short-term efficacy and safety of OFC for the treatment of bipolar depression are supported by results of four randomized, acute-phase studies. OFC has been associated with significantly greater depressive symptom improvement than placebo, and with higher rates of treatment response and remission than placebo and olanzapine monotherapy. OFC has also been shown to improve depressive symptoms to a greater degree than modestly dosed lamotrigine, with similar rates of positive treatment response and remission. Although OFC was generally well tolerated in each of the reviewed studies, clinically significant weight gain, adverse changes in glycemic and lipid profile, and prolactin elevation may complicate both short- and long-term treatment. OFC was not associated with significantly increased risk of treatment-emergent mania in any of the reviewed studies. The broader effectiveness of OFC for the treatment of bipolar depression across clinically relevant subtypes (eg, patients with bipolar II disorder and comorbid substance abuse) and over long-term follow-up are needed. Comparative effectiveness studies of OFC and other available agents are also needed in order to determine its place among other available options for treating acute bipolar depressive episodes.

No association between genetic markers in BDNF gene and lithium prophylaxis in a Greek sample

Abstract Lithium efficacy is, at least partially, under genetic control. We investigated the association between markers in BDNF and lithium prophylactic efficacy. A set of 10 SNPs within BDNF were genotyped in a sample of 83 bipolar patients. Response to lithium was assessed by presence or absence of any illness phases during a period of 3 years of longitudinal observation. No significant association was detected between the genetic variants tested in BDNF and lithium prophylaxis. Despite the negative association, limitations including small sample size suggest that larger scale genetic associations studies of these genes and lithium prophylaxis are nonetheless indicated.

Bipolar depression: overview and commentary

Depressive phases are the most prevalent component of bipolar disorders, even with modern treatment. Bipolar depressive morbidity is often misdiagnosed and is limited in response to available treatments. These conditions are especially debilitating and are associated with psychiatric comorbidity, substance abuse, functional disability, and increased mortality owing to early suicide and accidents, and later medical illnesses. There is growing awareness that bipolar depression is one of the greatest challenges in modern psychiatry. It is essential to differentiate various forms of depression, dysthymia, and dysphoric mixed states of bipolar disorders from the clinical features of more common, unipolar major depressive disorders. In bipolar depression, antidepressant responses often are unsatisfactory, and these agents probably are overused. Emerging treatments, including several anticonvulsant and modern antipsychotic drugs, as well as lithium-alone or in selected combinations-are partially effective for bipolar depression. Interest in recognizing bipolar depression and seeking more effective, specific, and safer treatments for it are growing.