Association between lithium treatment and renal, thyroid and parathyroid function: A cohort study of 6659 patients with bipolar disorder.

OBJECTIVES: Although potential adverse effects of lithium treatment on renal and endocrine systems have been extensively investigated, most prior studies are limited by selected populations and short follow-up. METHODS: Within the Psychiatric Services of the Central Denmark Region, we identified all patients with bipolar disorder and ≥1 serum-lithium (se-Li) measurements between January 1, 2013, and July 20, 2022, and reference patients with bipolar disorder matched on age, sex, and baseline creatinine. Outcomes were diagnoses of renal, thyroid and parathyroid disease, and blood tests measuring creatinine, estimated glomerular filtration rate (eGFR), thyroid-stimulating hormone (TSH), parathyroid hormone (PTH) and calcium. Analyses included unadjusted multilevel regression to describe changes in biochemical markers, and adjusted Cox regression to compare rates of disease/biochemical outcomes between lithium users and reference patients. RESULTS: Among 1646 lithium users (median age 36 years, 63% women) and 5013 reference patients, lithium users had decreasing TSH and eGFR, stable PTH, and increasing calcium levels over time. Lithium use was associated with increased rates of renal, thyroid and parathyroid disease, and levels of biochemical markers outside normal ranges (hazard rate ratios: 1.07-11.22), but the absolute number of severe outcomes was low (e.g., chronic kidney disease: N = 10, 0.6%). Notably, the rate of blood testing was substantially higher among lithium users than among reference patients (e.g., mean number of creatinine tests during the second year of follow-up: lithium users = 2.5, reference patients = 1.4). CONCLUSIONS: Severely adverse renal and endocrine outcomes are rare during lithium treatment. Observational studies of long-term lithium treatment are prone to detection bias.

Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats.

INTRODUCTION: The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. METHODOLOGY: Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220ng/3µl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium-pilocarpine model (3mEq/kg LiCl and 30mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. RESULTS: Rats injected with 120ng of GH did not had SE after 30mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70ng or 220ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. CONCLUSION: Our results indicate that, although GH has an anticonvulsive effect in the lithium-pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE.

Lithium-associated primary hyperparathyroidism:: An evaluation of screening and referral patterns in a southeastern veteran population.

BACKGROUND: Long-term lithium therapy has a well-established but under-recognized association with primary hyperparathyroidism. Rates of hypercalcemia, screening for primary hyperparathyroidism, and referral for parathyroidectomy were evaluated among United States veterans on long-term lithium therapy. METHODS: Patients undergoing chronic long-term lithium therapy (>12 months) were identified from 1999 to 2022. Demographics, long-term lithium therapy duration, post-treatment calcium, parathyroid hormone, creatinine, and vitamin D levels were abstracted. Rates of screening for hypercalcemia (calcium ≥10.2 mg/dL), primary hyperparathyroidism (parathyroid hormone ≥30 pg/mL in the setting of hypercalcemia), referral for parathyroidectomy, and outcomes were evaluated. RESULTS: A total of 1,356 patients underwent long-term lithium therapy, 514 of whom received chronic long-term lithium therapy. Baseline characteristics of patients with and without post-treatment hypercalcemia were compared. Of 148 patients with post-treatment hypercalcemia, 112 (74.7%) underwent no further evaluation for primary hyperparathyroidism, while 36 (25.3%) patients had a parathyroid hormone level recorded. Although 33 (91.7%) hypercalcemic patients screened positive for primary hyperparathyroidism, only 5 (13%) were referred for parathyroidectomy. Of the 4 patients who underwent parathyroidectomy, mean calcium was 11.2 mg/dL (range 11.1-11.4), and mean parathyroid hormone was 272 pg/mL (range 108-622). Three patients were localized on preoperative imaging, 2 of whom underwent unilateral exploration with cure, with 1 experiencing recurrence at 31 months. The remaining patient who localized preoperatively underwent bilateral exploration and had 2 ipsilateral glands resected and persistence. The patient who did not localize preoperatively underwent bilateral exploration with 3 gland resection and cure. CONCLUSIONS: Screening for primary hyperparathyroidism and referral for parathyroidectomy are underutilized in United States veterans undergoing chronic long-term lithium therapy. Institutional protocols to standardize screening, surveillance, and referrals to endocrinology/endocrine surgery could benefit this population at increased risk for primary hyperparathyroidism.

Subjects suffering from bipolar disorder taking lithium are less likely to report physical pain: a FACE-BD study.

BACKGROUND: Physical pain is a common issue in people with bipolar disorder (BD). It worsens mental health and quality of life, negatively impacts treatment response, and increases the risk of suicide. Lithium, which is prescribed in BD as a mood stabilizer, has shown promising effects on pain. METHODS: This naturalistic study included 760 subjects with BD ( FACE-BD cohort) divided in two groups: with and without self-reported pain (evaluated with the EQ-5D-5L questionnaire). In this sample, 176 subjects were treated with lithium salts. The objectives of the study were to determine whether patients receiving lithium reported less pain, and whether this effect was associated with the recommended mood-stabilizing blood concentration of lithium. RESULTS: Subjects with lithium intake were less likely to report pain (odds ratio [OR] = 0.59, 95% confidence interval [CI], 0.35-0.95; p = 0.036) after controlling for sociodemographic variables, BD type, lifetime history of psychiatric disorders, suicide attempt, personality traits, current depression and anxiety levels, sleep quality, and psychomotor activity. Subjects taking lithium were even less likely to report pain when lithium concentration in blood was ≥0.5 mmol/l (OR = 0.45, 95% CI, 0.24-0.79; p = 0.008). CONCLUSIONS: This is the first naturalistic study to show lithium's promising effect on pain in subjects suffering from BD after controlling for many confounding variables. This analgesic effect seems independent of BD severity and comorbid conditions. Randomized controlled trials are needed to confirm the analgesic effect of lithium salts and to determine whether lithium decreases pain in other vulnerable populations.

Antiepileptogenic Effects of Anakinra, Lamotrigine and Their Combination in a Lithium-Pilocarpine Model of Temporal Lobe Epilepsy in Rats.

Temporal lobe epilepsy is a common, chronic disorder with spontaneous seizures that is often refractory to drug therapy. A potential cause of temporal lobe epilepsy is primary brain injury, making prevention of epileptogenesis after the initial event an optimal method of treatment. Despite this, no preventive therapy for epilepsy is currently available. The purpose of this study was to evaluate the effects of anakinra, lamotrigine, and their combination on epileptogenesis using the rat lithium-pilocarpine model of temporal lobe epilepsy. The study showed that there was no significant difference in the number and duration of seizures between treated and untreated animals. However, the severity of seizures was significantly reduced after treatment. Anakinra and lamotrigine, alone or in combination, significantly reduced neuronal loss in the CA1 hippocampus compared to the control group. However, the drugs administered alone were found to be more effective in preventing neuron loss in the hippocampal CA3 field compared to combination treatment. The treatment alleviated the impairments in activity level, exploratory behavior, and anxiety but had a relatively weak effect on TLE-induced impairments in social behavior and memory. The efficacy of the combination treatment did not differ from that of anakinra and lamotrigine monotherapy. These findings suggest that anakinra and lamotrigine, either alone or in combination, may be clinically useful in preventing the development of histopathological and behavioral abnormalities associated with epilepsy.

Absolute and Relative Risks of Kidney Outcomes Associated With Lithium vs Valproate Use in Sweden.

Importance: Among patients with bipolar disorder, discordant findings have been published on the nephrotoxic effects of lithium therapy. Objective: To quantify absolute and relative risks of chronic kidney disease (CKD) progression and acute kidney injury (AKI) in people who initiated lithium compared with valproate therapy and to investigate the association between cumulative use and elevated lithium levels and kidney outcomes. Design, Setting, and Participants: This cohort study had a new-user active-comparator design and used inverse probability of treatment weights to minimize confounding. Included patients initiated therapy with lithium or valproate from January 1, 2007, to December 31, 2018, and had a median follow-up of 4.5 years (IQR, 1.9-8.0 years). Data analysis began in September 2021, using routine health care data from the period 2006 to 2019 from the Stockholm Creatinine Measurements project, a recurrent health care use cohort of all adult residents in Stockholm, Sweden. Exposures: New use of lithium vs new use of valproate and high (>1.0 mmol/L) vs low serum lithium levels. Main Outcomes and Measures: Progression of CKD (composite of >30% decrease relative to baseline estimated glomerular filtration rate [eGFR] and kidney failure), AKI (by diagnosis or transient creatinine elevations), new albuminuria, and annual eGFR decrease. Outcomes by attained lithium levels were also compared in lithium users. Results: The study included 10 946 people (median [IQR] age, 45 [32-59] years; 6227 female [56.9%]), of whom 5308 initiated lithium therapy and 5638 valproate therapy. During follow-up, 421 CKD progression events and 770 AKI events were identified. Compared with patients who received valproate, those who received lithium did not have increased risk of CKD (hazard ratio [HR], 1.11 [95% CI, 0.86-1.45]) or AKI (HR, 0.88 [95% CI, 0.70-1.10]). Absolute 10-year CKD risks were low and similar: 8.4% in the lithium group and 8.2% in the valproate group. No difference in the risk of developing albuminuria or the annual rate of eGFR decrease was found between groups. Among more than 35 000 routine lithium tests, only 3% of results were in the toxic range (>1.0 mmol/L). Lithium values greater than 1.0 mmol/L, compared with lithium values of 1.0 mmol/L or less, were associated with increased risk of CKD progression (HR, 2.86; 95% CI, 0.97-8.45) and AKI (HR, 3.51; 95% CI, 1.41-8.76). Conclusions and Relevance: In this cohort study, compared with new use of valproate, new use of lithium was meaningfully associated with adverse kidney outcomes, with low absolute risks that did not differ between therapies. However, elevated serum lithium levels were associated with future kidney risks, particularly AKI, emphasizing the need for close monitoring and lithium dose adjustment.

Absence of E-Cadherin and ß-Catenin in the Basal Plasma Membrane of Collecting Duct Cells During NDI Development and Recovery.

Lithium (Li) induces severe polyuria and polydipsia in up to 40% of patients undergoing Li treatment. In rats, Li treatment induces a reversible cellular remodeling of the collecting duct (CD), decreasing the fraction of principal-to-intercalated cells. To investigate the potential role of adherens junction proteins, we performed immunohistochemistry on kidney cross-sections from rats treated with Li as well as rats undergoing recovery on a normal diet following 4 weeks of Li-treatment. We performed immunoelectron microscopy on cryosections to determine the ultrastructural localizations. Immunohistochemistry showed that E-cadherin and ß-catenin were present in both the lateral and basal plasma membrane domains of CD cells. Immunoelectron microscopy confirmed that ß-catenin was localized both to the lateral and the basal plasma membrane. The basal localization of both proteins was absent from a fraction of mainly principal cells after 10 and 15 days of Li-treatment. After 4 weeks of Li-treatment few to no cells were absent of E-cadherin and ß-catenin at the basal plasma membrane. After 12 and 19 days of recovery some cells exhibited an absence of basal localization of both proteins. Thus, the observed localizational changes of E-cadherin and ß-catenin appear before the cellular remodeling during both development and recovery from Li-NDI.

A Single High Dose of Flufenamic Acid in Rats does not Reduce the Damage Associated with the Rat Lithium-Pilocarpine Model of Status Epilepticus but Leads to Deleterious Outcomes.

BACKGROUND: Epilepsy is one of the most common neurologic diseases, and around 30% of all epilepsies, particularly the temporal lobe epilepsy (TLE), are highly refractory to current pharmacological treatments. Abnormal synchronic neuronal activity, brain glucose metabolism alterations, neurodegeneration and neuroinflammation are features of epilepsy. Further, neuroinflammation has been shown to contribute to dysregulation of neuronal excitability and the progression of epileptogenesis. Flufenamic acid (FLU), a non-steroidal anti-inflammatory drug, is also characterized by its wide properties as a dose-dependent ion channel modulator. In this context, in vitro studies have shown that it abolishes seizure-like events in neocortical slices stimulated with a gamma-aminobutyric acid A (GABAA) receptor blocker. However, little is known about its effects in animal models. Thus, our goal was to assess the efficacy and safety of a relatively high dose of FLU in the lithium-pilocarpine rat model of status epilepticus (SE). This animal model reproduces many behavioral and neurobiological features of TLE such as short-term brain hypometabolism, severe hippocampal neurodegeneration and inflammation reflected by a marked reactive astrogliosis. METHODS: FLU (100 mg/kg, i.p.) was administered to adult male rats, 150 min before SE induced by pilocarpine. Three days after the SE, brain glucose metabolism was assessed by 2-deoxy-2-[18F]-fluoro-D-glucose ([18F]FDG) positron emission tomography (PET). Markers of hippocampal integrity, neurodegeneration and reactive astrogliosis were also evaluated. RESULTS: FLU neither prevented the occurrence of the SE nor affected brain glucose hypometabolism as assessed by [18F]FDG PET. Regarding the neurohistochemical studies, FLU neither prevented neuronal damage nor hippocampal reactive astrogliosis. On the contrary, FLU increased the mortality rate and negatively affected body weight in the rats that survived the SE. CONCLUSIONS: Our results do not support an acute anticonvulsant effect of a single dose of FLU. Besides, FLU did not show short-term neuroprotective or anti-inflammatory effects in the rat lithium-pilocarpine model of SE. Moreover, at the dose administered, FLU resulted in deleterious effects.

Estimating the per-protocol effect of lithium on suicidality in a randomized trial of individuals with depression or bipolar disorder.

BACKGROUND: The CSP590 randomized trial was designed to estimate the effect of lithium on suicidality. After a third of the intended number of participants were enrolled, the hazard ratio of suicidality was 1.10 (95% CI: 0.77, 1.55). Based on this, the trial was stopped for futility. However, only 17% of patients adhered to the specified protocol. AIMS: The objective was to estimate the per-protocol effect of lithium on suicidality, that is, the effect of adhering to the treatment strategies as specified in the protocol. METHODS: We stopped individuals' follow-up if/when they showed evidence of nonadherence. We then conducted the analysis in the restricted sample, adjusting for prognostic factors that predict adherence via inverse probability weighting. The primary outcome was the 12-month risk of suicidality (including death from suicide, suicide attempt, interrupted attempt, hospitalization specifically to prevent suicide). RESULTS: The estimated 12-month risk of suicidality was 18.8% for lithium, and 24.3% for placebo. The risk ratio was 0.78 (95% CI: 0.43, 1.37) and the risk difference -5.5 percentage points (95% CI: -17.5, 5.5). Results were consistent across sensitivity analyses. CONCLUSIONS: With one-third of the targeted sample size, lithium effects (compared with placebo) ranging between a 17.5% reduction and a 5.5% increase in the risk of suicidality were highly compatible with the data. Thus, a protective effect of lithium on suicidality among patients with bipolar disorder or major depressive disorder cannot be ruled out. Trials should incorporate adequate per-protocol analyses into the decision-making processes for stopping trials for futility.

An evaluation of the effect of lithium on taxane-induced neuropathy.

PURPOSE: No medications are known to protect against chemotherapy-induced peripheral neuropathy (CIPN). Pre-clinical models suggest that lithium may lessen taxane-induced neuropathy. Our aim was to use clinical data to assess whether concurrent lithium usage decreased the frequency or severity of CIPN in patients receiving taxane chemotherapy. METHODS: A retrospective analysis was performed using the electronic health record at Mayo Clinic to identify all patients prescribed concurrent lithium and paclitaxel. Four controls were matched to each case based on clinical variables. Neuropathy severity was graded from available patient and clinician reports. Rates of any neuropathy, dose reduction for CIPN, and treatment discontinuation for CIPN were compared. Conditional regression analysis was performed with propensity score matching. RESULTS: Six patients, receiving concurrent lithium and paclitaxel, were included in the analysis, and compared to 24 control cases. A similar number of paclitaxel cycles were administered to both groups. Any neuropathy was experienced by 33% (2/6) of patients receiving lithium and 38% (9/24) patients who did not receive lithium (p = 1.000). There was no difference in neuropathy severity (p = 0.8565), rate of chemotherapy dose reduction (17% vs. 17%, p = 1.000), or treatment discontinuation (17% vs 4%, p = 0.3655) for CIPN. In the propensity score analysis, the odds ratio for developing any neuropathy was 0.63 (95% confidence interval, 0.06 to 6.96, p = 0.7079). CONCLUSIONS: Lithium does not appear to significantly lessen the risk of neuropathy for patients receiving paclitaxel. IMPLICATIONS FOR CANCER SURVIVORS: Targeted approaches for preventing CIPN are desperately needed. Despite sound scientific rationale, the current study did not identify neuroprotective properties of lithium.

Association Between Estimated Geocoded Residential Maternal Exposure to Lithium in Drinking Water and Risk for Autism Spectrum Disorder in Offspring in Denmark.

Importance: Lithium is a naturally occurring and trace element that has mood-stabilizing effects. Maternal therapeutic use of lithium has been associated with adverse birth outcomes. In animal models, lithium modulates Wnt/ß-catenin signaling that is important for neurodevelopment. It is unknown whether exposure to lithium in drinking water affects brain health in early life. Objective: To evaluate whether autism spectrum disorder (ASD) in offspring is associated with maternal exposure to lithium in drinking water during pregnancy. Design, Setting, and Participants: This nationwide population-based case-control study in Denmark identified 8842 children diagnosed with ASD born from 2000 through 2013 and 43 864 control participants matched by birth year and sex from the Danish Medical Birth Registry. These data were analyzed from March 2021 through November 2022. Exposures: Geocoded maternal residential addresses during pregnancy were linked to lithium level (range, 0.6 to 30.7 µg/L) in drinking water estimated using kriging interpolation based on 151 waterworks measurements of lithium across all regions in Denmark. Main Outcomes and Measures: ASD diagnoses were ascertained using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes recorded in the Danish Psychiatric Central Register. The study team estimated odds ratios (ORs) and 95% CIs for ASD according to estimated geocoded maternal exposure to natural source of lithium in drinking water as a continuous (per IQR) or a categorical (quartile) variable, adjusting for sociodemographic factors and ambient air pollutants levels. The study team also conducted stratified analyses by birth years, child's sex, and urbanicity. Results: A total of 8842 participants with ASD (male, 7009 [79.3%]) and 43 864 control participants (male, 34 749 [79.2%]) were studied. Every IQR increase in estimated geocoded maternal exposure to natural source of lithium in drinking water was associated with higher odds for ASD in offspring (OR, 1.23; 95% CI, 1.17-1.29). Elevated odds among offspring for ASD were estimated starting from the second quartile (7.36 to 12.67 µg/L) of estimated maternal exposure to drinking water with lithium and the OR for the highest quartile (more than 16.78 µg/L) compared with the reference group (less than 7.39 µg/L) was 1.46 (95% CI, 1.35-1.59). The associations were unchanged when adjusting for air pollution exposures and no differences were apparent in stratified analyses. Conclusions and Relevance: Estimated maternal prenatal exposure to lithium from naturally occurring drinking water sources in Denmark was associated with an increased ASD risk in the offspring. This study suggests that naturally occurring lithium in drinking water may be a novel environmental risk factor for ASD development that requires further scrutiny.

Safety and efficacy of lithium in patients with amyotrophic lateral sclerosis: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: This study provides a systematic review and meta-analysis of randomized controlled trials (RCTs) investigating the safety and efficacy of lithium in amyotrophic lateral sclerosis (ALS) patients. METHODS: PubMed, Web of Science, Cochrane CENTRAL, Scopus, and Your Journals@Ovid were searched up to 9 December 2022. RCTs investigating lithium, either alone or with any supplement, in ALS patients were included. Meta-analysis was performed using RevMan and results are presented in forest plot. RESULTS: Four RCTs with 469 patients met the inclusion criteria and were included in our study. Lithium doses varied among the included studies and one study used a combined therapy of lithium with valproate. Meta-analysis showed no difference between lithium and placebo regarding severe adverse events (odds ratio = 1.13, 95% confidence interval: 0.73 to 1.75, P = 0.58). No significant differences were observed with regard to survival rate between the two groups (hazard ratio = 0.95, 95% confidence interval: 0.65 to 1.37, P = 0.77). There were also no significant differences between the two groups with regard to average changes of revised amyotrophic lateral sclerosis functional rating scale (P = 0.35) and forced vital capacity percentage predicted (P = 0.73). Subgroup analysis showed no significant differences regarding all investigated outcomes either for lithium alone or lithium with valproate. CONCLUSION: Current evidence suggests a safety profile with no benefit of lithium for ALS. However, given the limited number of RCTs and the safety findings, we recommend further well-designed RCTs to investigate lithium and valproate in ALS patients.

Impact of lithium on mortality among older adults with major psychiatric disorders: A 5-year prospective multicenter study.

OBJECTIVE: Prior studies report conflicting results about the association between lithium use and all-cause mortality. In addition, data are scarce on this association among older adults with psychiatric disorders. In this report, we sought to examine the associations of lithium use with all-cause mortality and specific causes of death (i.e., due to cardiovascular disorder, non-cardiovascular disease, accident, or suicide) among older adults with psychiatric disorders during a 5-year follow-up period. METHODS: In this observational epidemiological study, we used data from 561 patients belonging to a Cohort of individuals with Schizophrenia or Affective disorders aged 55-years or more (CSA). Patients taking lithium at baseline were first compared to patients not taking lithium, and then to patients taking (i) antiepileptics and (ii) atypical antipsychotics in sensitivity analyses. Analyses were adjusted for socio-demographic (e.g., age, gender), clinical characteristics (e.g., psychiatric diagnosis, cognitive functioning), and other psychotropic medications (e.g. benzodiazepines). RESULTS: There was no significant association between lithium use and all-cause mortality [AOR=1.12; 95%CI=0.45-2.79; p=0.810] or disease-related mortality [AOR=1.37; 95%CI=0.51-3.65; p=0.530]. None of the 44 patients taking lithium died from suicide, whereas 4.0% (N=16) of patients not receiving lithium did. CONCLUSION: These findings suggest that lithium may not be associated with all-cause or disease-related mortality and might be associated with reduced risk of suicide in this population. They argue against the underuse of lithium as compared with antiepileptics and atypical antipsychotics among older adults with mood disorders.

Iatrogenic endocrine complications of lithium therapy.

Lithium is a cation, similar to sodium and potassium, affecting ion transport. It is used in the medical field as a treatment of bipolar disorders. The main endocrine complications of lithium treatment affect thyroid and parathyroid glands, in association with renal complications. Thyroid adverse effects, which are more frequent in women, comprise hypothyroidism, goiter, or sometimes hyperthyroidism, through interference with the iodine symporter. The increase in thyroid volume is early. Prevalence of goiter is 4 times higher than in the general population and hypothyroidism (8-20%) more frequent in case of pre-existing thyroid autoimmunity. Hyperthyroidism likely to worsen mood is reported in 5% of cases but the causal link to lithium is unproven. An increase in serum calcium and PTH occurs in 30% of cases, as lithium stimulates parathyroid cell proliferation by activating the Wnt pathway. The risk of hyperparathyroidism, by adenoma and especially by hyperplasia, is 5 times higher than in the general population, with the particularity of frequent low urine calcium by action on the calcium-sensing receptor (CaSR). Renal complications include risk of acute or chronic renal failure and nephrogenic diabetes insipidus, which is a factor for hypernatremia and hypercalcemia through dehydration. Nephrogenic diabetes insipidus is not always reversible after lithium therapy discontinuation. Metabolically, weight gain can be observed, but rather less than with other psychotropic drugs, and lithium does not in itself induce diabetes. At pituitary level, corticotropic activation is frequent, but implicating the disease rather than lithium. Lithium treatment induces little or no hyperprolactinemia. Regular monitoring of serum calcium, the ionogram, creatinine and TSH is recommended in lithium treatment.

Low-level lithium in drinking water and subsequent risk of dementia: Cohort study.

BACKGROUND: Lithium, a mood stabilizer, is known to exhibit neuroprotective effects in animal models and may have anti-dementia effects. AIMS: We used data from Scottish Mental Survey 1932, a population-based cohort study, to investigate the association between lithium in drinking water and dementia rate in humans. METHOD: Lithium levels in drinking water from 285 sampling sites across Scotland dating from 2014 were obtained from the sole public water provider (Scottish Water). Dementia and non dementia cases were identified from cohort data by electronic health records until 2012, and linked to postcode. RESULTS: The mean lithium level at all sampling sites was 1.45 µg/L (SD 1.83, range 0.5-18.2) and was 1.26 (SD 0.63, range 0.55-9.19) for sites matched to participant data. Of 37,597 study members, 3605 developed dementia until June 2012. Lithium levels were positively associated with the risk of dementia in women (highest in second quartile, HR 1.17, 95%CI 1.04-1.32), but there was no relationship in men (highest in second quartile, HR 0.95, 95% CI 0.81-1.12). The pattern of association was explored further by decile, and in females there was an association between lithium level and increased dementia risk compared to the lowest decile (0.55-0.68 µg/L) in all deciles except the highest, corresponding with lithium levels 0.68-2.1 µg/L. CONCLUSIONS: Lithium levels in drinking water are very low across Scotland which limited detection of potential effect. Our results do not support an association between extremely low levels of lithium and later dementia risk. We found a trend to increased risk in females at lithium levels below but not above 2.1 µg/L.