The incidence and clinical correlates of lithium toxicity: a retrospective review

The Gilded Clot: Review of Metal-Modulated Platelet Activation, Coagulation, and Fibrinolysis

The processes of blood coagulation and fibrinolysis that in part maintain the physical integrity of the circulatory system and fluidity of its contents are complex as they are critical for life. While the roles played by cellular components and circulating proteins in coagulation and fibrinolysis are widely acknowledged, the impact of metals on these processes is at best underappreciated. In this narrative review we identify twenty-five metals that can modulate the activity of platelets, plasmatic coagulation, and fibrinolysis as determined by in vitro and in vivo investigations involving several species besides human beings. When possible, the molecular interactions of the various metals with key cells and proteins of the hemostatic system were identified and displayed in detail. It is our intention that this work serve not as an ending point, but rather as a fair evaluation of what mechanisms concerning metal interactions with the hemostatic system have been elucidated, and as a beacon to guide future investigation.

General practitioners' perceptions of pharmacists working in general practice: a qualitative interview study

BACKGROUND

Pharmacists are being increasingly employed as part of general practice teams globally, and their input has been associated with several clinical and economic benefits. However, there is a paucity of research focussing on general practitioners' (GPs') perceptions of pharmacist integration into practices in countries where this novel role for pharmacists is yet to become commonplace.

OBJECTIVE

To explore GPs' perceptions of integrating pharmacists into general practices and to identify the behavioural determinants of GPs integrating pharmacists into practices.

METHODS

Semistructured interviews were conducted with GPs practising in Ireland, who were sampled using a combination of purposive, convenience, and snowball sampling. Interviews were audio-recorded and transcribed verbatim, which then were analysed using conventional content analysis and directed content analysis employing the Theoretical Domains Framework (TDF).

RESULTS

Seventeen GPs were interviewed between November 2021 and February 2022. Seven TDF domains were identified as predominant in influencing GPs' perceptions of pharmacist integration into general practices. These perceptions were mostly positive, especially regarding patient outcomes, cost savings, and improving access to care. However, there were concerns about funding the role, affecting others' workloads, and pharmacists' training needs to work in practices.

CONCLUSION

This study's theory-informed insight provides a deeper understanding of GPs' perceptions of pharmacists working in general practice and behaviours which can be targeted to help optimize integration. These findings should be utilized in future service development to preempt and address GPs' concerns ahead of pharmacist integration, as well as to inform the development of general practice-based pharmacist roles going forward.

Hemodialysis Treatment for Patients with Lithium Poisoning

BACKGROUND

Hemodialysis is often recommended to treat severe lithium poisoning. Nevertheless, the application rate of hemodialysis in patients with lithium poisoning is varied across different groups and the effect of hemodialysis is still undetermined. Therefore, this study aimed to analyze the hemodialysis rate of patients with lithium poisoning and to explore the clinical features of lithium-poisoned-patients treated or untreated with hemodialysis.

METHODS

Between 2001 and 2019, 36 patients treated at the Chang Gung Memorial Hospital for the management of lithium poisoning were stratified according to whether they were treated with hemodialysis (n = 7) or not (n = 29).

RESULTS

The patients were aged 50.7 ± 18.1 years. The poisoning patterns were acute on chronic (61.1%), chronic (25.0%) and acute (13.9%). The precipitating factors of dehydration and infection were noted in 36.1% and 25.0% of patients, respectively. Bipolar disorder (72.2%), depressive disorder (27.8%) and psychotic disorder (11.1%) were the top three psychiatric comorbidities. The hemodialysis group not only had a lower Glasgow Coma Scale (GCS) score (p = 0.001) but also had a higher respiratory failure rate (p = 0.033), aspiration pneumonia rate (p = 0.033) and acute kidney injury network (AKIN) score (p = 0.002) than the non-hemodialysis group. Although none of the patients died of lithium poisoning, the hemodialysis group required more endotracheal intubation (p = 0.033), more intensive care unit admission (p = 0.033) and longer hospitalization (p = 0.007) than the non-hemodialysis group.

CONCLUSION

The analytical results revealed zero mortality rate and low hemodialysis rate (1.9%). Compared with patients without hemodialysis, patients receiving hemodialysis suffered severer lithium-associated complications and needed a more intensive care unit admission and longer hospital stay.

Neurotoxicity in chronic lithium poisoning

BACKGROUND

Lithium-induced neurotoxicity typically occurs with chronic accumulation rather than following acute overdose. There is little emphasis in the literature on the protracted nature of lithium neurotoxicity long after the lithium concentration returns to the therapeutic range.

AIMS

To characterise lithium neurotoxicity, with a view of increasing awareness of this important phenomenon.

METHODS

This is a retrospective observational study of patients presenting with lithium-induced neurotoxicity over a 5-year period to a clinical toxicology unit. Patients were identified through the unit's database, and clinical notes were analysed.

RESULTS

There were 22 patients, with a median age of 65 (range: 36-89) years. Six patients (27%) had previous lithium toxicity, and nine (41%) were regularly prescribed medications that impair lithium excretion. The median lithium concentration on presentation was 2.2 mmol/L, taking a median of 3 days to return to the therapeutic range. Reversible acute kidney injury was observed in 21 patients (95%) on presentation. The median length of stay was 13 (range: 3-95) days due mostly to delayed neurological recovery. Confusion was the predominant symptom, present in 21 (95%) patients, followed by tremors (18(82%)) and ataxia (16(73%)). Multiple investigations were performed to exclude delirium differentials, including 11 computed tomography (CT) and five magnetic resonance imaging (MRI) brain scans, all unremarkable.

CONCLUSIONS

Lithium neurotoxicity has a prolonged course. Its severity correlates poorly with lithium concentrations, which normalise quickly. Most poisonings occur in elderly patients with acute kidney injury. Prolonged delirium often prompts multiple unnecessary investigations. Rationalisation of lithium therapy is important in elderly patients.

The clinical characteristics and correlates of lithium toxicity in a tertiary referral centre

INTRODUCTION

Lithium is a medication indicated for the treatment of bipolar disorder and treatment-resistant depression, with a narrow therapeutic index. Overdose, either acute or chronic can result in neurological symptoms, requiring dialysis and admission to intensive care in some cases. Lithium toxicity is avoidable with careful monitoring. However, we have noted several recent cases of lithium toxicity in our local service and thus sought to investigate this issue in a more systematic manner.

AIM

We aimed to quantify the incidence of lithium toxicity in our local population over a single year and identify the patients most at risk. We also aimed to generate clinical recommendations on the prevention of lithium toxicity to improve patient safety.

METHOD

We identified the incidence of lithium toxicity in our local population, by searching the hospital pathology database for patients with serum lithium levels greater than 1.0 mmol/L. We examined the available clinical notes for these patients.

RESULTS

We identified 74 serum lithium readings above 1.0 mmol/L measured in 44 individual patients. The highest recorded level was 3.2 mmol/L. Of these, 11 patients were aged 65 years or older. Hospital admission was required in 14 cases. There were missing data of note: 29.5% had no renal function/eGFR measurement at time of toxicity and 52.3% without a baseline eGFR.

CONCLUSION

Lithium toxicity is common in our population. Given the narrow therapeutic index, this demonstrates the need for careful monitoring and prescribing, especially patients aged 65 and over.

Outcomes of patient education practices to optimize the safe use of lithium: A literature review

Introduction:

Lithium is commonly used to treat various psychiatric disorders and is particularly effective in the maintenance phase of bipolar disorder. Unfortunately, this drug has a narrow therapeutic index and, if not monitored regularly, can result in toxicity. Therefore, for lithium to be prescribed safely, clinicians must ensure that patients are well educated on lithium toxicity, its prevention, and symptom recognition. This article summarizes studies that investigated lithium education strategies to help promote the safe use of lithium.

Methods:

Four electronic databases were searched using key terms and subject headings. Reference lists of relevant papers were also reviewed. The search was limited to literature published in English, without year limits. Eligible studies examined lithium patient education and the impact on patients' knowledge of safe lithium use.

Results:

Of a total of 517 citations that were retrieved from the electronic database search, 12 were selected for inclusion in this review. Most of the studies included assessed the effect of lithium education on various aspects of patients' knowledge, including but not limited to, lithium toxicity. Of the studies assessing the correlation between lithium knowledge and lithium levels, most demonstrated a positive correlation between lithium knowledge and lithium levels that were more stable and within the higher end of the recommended therapeutic range.

Conclusions:

Studies evaluating lithium patient education and its effect on improving the safe use of lithium are limited. Nevertheless, this literature review highlights that lithium patient education is critical to promote its safe use.

Lithium monitoring patterns in the United Kingdom and Ireland: Can shared care agreements play a role in improving monitoring quality? A systematic review

BACKGROUND

The appropriate monitoring of patients on lithium therapy has been the subject of extensive research in the form of clinical audits and surveys culminating in the development of specific guidelines to help clinicians provide optimal care for patients on lithium. The concept of 'shared care' has also gained attention in the literature with various types of shared care interventions being introduced as potential ways of improving communication between primary and secondary care.

OBJECTIVES

This article aims to (1) review the literature evaluating lithium monitoring practices in the United Kingdom and Ireland in the last 25 years and (2) determine whether locally agreed shared care agreements have the potential to improve monitoring quality.

METHODS

A literature search was conducted using the following databases: PubMed, Scopus, Web of Science, Academic Search Premier, CINAHL and PsychInfo. A total of 12 studies were selected for review including 11 audits/prospective chart reviews and one qualitative study using semi-structured interviews.

CONCLUSIONS

Overall, the quality of lithium monitoring seems to be improving throughout the years. However, none of the studies reviewed revealed complete adherence to monitoring guidelines. This may be due to a lack of effective communication between primary and secondary care. Several shared care interventions have been described in the literature but there is a paucity of studies concerned with the effects of local shared care arrangements designed for the specific purpose of lithium monitoring. Nonetheless, the extant data suggests that such agreements may help improve monitoring standards by allowing the responsibilities for managing the prescribing and monitoring of lithium to be more clearly defined and shared between primary and secondary care.

Lithium intoxication: Incidence, clinical course and renal function - a population-based retrospective cohort study

When prescribing lithium, the risk of toxicity remains a concern. In this study, we examined a cohort of patients exposed to lithium between 1997 and 2013. The aims of this study were to determine the frequency of lithium intoxication and to evaluate the clinical course and changes in renal function. Of 1340 patients, 96 had experienced at least one episode of lithium levels ⩾1.5 mmol/L, yielding an incidence of 0.01 per patient-year. Seventy-seven patients available for review had experienced 91 episodes, of whom 34% required intensive care and 13% were treated with haemodialysis. There were no fatalities. Acute kidney injury occurred, but renal function at baseline was not different to renal function after the episode. Renal impairment was often associated with co-morbidities and other factors. Both intermittent and continuous-venovenous haemodialysis were used, but the clearance of continuous-venovenous haemodialysis can be too low in cases where large amounts of lithium have been ingested. Saline and forced diuresis have been used and are safe. Lithium intoxication seems rare and can be safely managed in most cases. Physicians should not withhold lithium for fear of intoxication in patients who benefit from it. Yet, physicians should have a low threshold to screen for toxicity.

Stratifying Risk for Renal Insufficiency Among Lithium-Treated Patients: An Electronic Health Record Study

Although lithium preparations remain first-line treatment for bipolar disorder, risk for development of renal insufficiency may discourage their use. Estimating such risk could allow more informed decisions and facilitate development of prevention strategies. We utilized electronic health records from a large New England health-care system between 2006 and 2013 to identify patients aged 18 years or older with a lithium prescription. Renal insufficiency was identified using the presence of renal failure by ICD9 code or laboratory-confirmed glomerular filtration rate below 60 ml/min. Logistic regression was used to build a predictive model in a random two-thirds of the cohort, which was tested in the remaining one-third. Risks associated with aspects of pharmacotherapy were also examined in the full cohort. We identified 1445 adult lithium-treated patients with renal insufficiency, matched by risk set sampling 1 : 3 with 4306 lithium-exposed patients without renal insufficiency. In regression models, features associated with risk included older age, female sex, history of smoking, history of hypertension, overall burden of medical comorbidity, and diagnosis of schizophrenia or schizoaffective disorder (p<0.01 for all contrasts). The model yielded an area under the ROC curve exceeding 0.81 in an independent testing set, with 74% of renal insufficiency cases among the top two risk quintiles. Use of lithium more than once daily, lithium levels greater than 0.6 mEq/l, and use of first-generation antipsychotics were independently associated with risk. These results suggest the possibility of stratifying risk for renal failure among lithium-treated patients. Once-daily lithium dosing and maintaining lower lithium levels where possible may represent strategies for reducing risk.

Effect of Adenine on Clozapine-induced Neutropenia in Patients with Schizophrenia: A Preliminary Study

Objective

This study examined the utility of adenine for preventing clozapine-induced neutropenia.

Methods

This retrospective study examined the effect of adenine on clozapine-induced neutropenia in patients with treatment-resistant schizophrenia and was conducted at Okehazama Hospital in Japan from July 2010 to June 2013. Adenine was available for use from June 2011 onwards. Twenty-one patients started receiving clozapine treatment from July 2010 to April 2011 (the pre-adenine adoption group), and 47 patients started receiving it from May 2011 to June 2013 (the post-adenine adoption group). The effects of adenine were assessed based on changes in the patients’ leukocyte counts and the frequency of treatment discontinuation due to clozapine-induced neutropenia.

Results

Sixty-eight patients were treated with clozapine from July 2010 to June 2013. Of the 21 patients in the pre-adenine adoption group, 4 discontinued treatment due to clozapine-induced neutropenia, whereas only 2 of the 47 patients in the post-adenine adoption group discontinued treatment. The frequency of treatment discontinuation due to clozapine-induced neutropenia was significantly lower in post-adenine adoption group than in the pre-adenine adoption group (p=0.047).

Conclusion

Adenine decreased the frequency of treatment discontinuation due to clozapine-induced neutropenia. Our data suggest that combined treatment with clozapine and adenine is a safe and effective strategy against treatment-resistant schizophrenia.

Drug-induced cerebellar ataxia: a systematic review

BACKGROUND AND OBJECTIVES

Cerebellar ataxia can be induced by a large number of drugs. We here conducted a systemic review of the drugs that can lead to cerebellar ataxia as an adverse drug reaction (ADR).

METHODS

We performed a systematic literature search in Pubmed (1966 to January 2014) and EMBASE (1988 to January 2014) to identify all of the drugs that can have ataxia as an ADR and to assess the frequency of drug-induced ataxia for individual drugs. Furthermore, we collected reports of drug-induced ataxia over the past 20 years in the Netherlands by querying a national register of ADRs.

RESULTS

Drug-induced ataxia was reported in association with 93 individual drugs (57 from the literature, 36 from the Dutch registry). The most common groups were antiepileptic drugs, benzodiazepines, and antineoplastics. For some, the number needed to harm was below 10. Ataxia was commonly reversible, but persistent symptoms were described with lithium and certain antineoplastics.

CONCLUSIONS

It is important to be aware of the possibility that ataxia might be drug-induced, and for some drugs the relative frequency of this particular ADR is high. In most patients, symptoms occur within days or weeks after the introduction of a new drug or an increase in dose. In general, ataxia tends to disappear after discontinuation of the drug, but chronic ataxia has been described for some drugs.

Acute renal failure induced by markedly decreased appetite secondary to a depressive episode after discontinuation of long-term lithium therapy in an elderly patient with bipolar disorder

Some elderly patients on chronic lithium therapy for bipolar disorder and their doctors may be faced with a therapeutic dilemma over whether or not to continue prescribing/taking lithium given their increased risk of reduced renal function. We present the case of a 78-year-old woman with bipolar disorder who discontinued lithium therapy due to increased risk factors for renal injury. After discontinuation, she experienced markedly decreased appetite secondary to a depressive episode, and developed acute renal failure, which subsequently progressed to a more advanced stage of chronic kidney disease. This case suggests that extreme care must be taken to prevent the recurrence of depression in elderly patients with bipolar disorder who discontinue lithium therapy, even when they had been emotionally stable for a long time while receiving lithium. Medications other than lithium for bipolar disorder may be needed at the time lithium therapy is discontinued.

The effects of lithium on renal function in older adults--a systematic review

Chronic renal failure (CRF) and nephrogenic diabetes insipidus (NDI) are potential consequences of chronic lithium use, while acute renal failure (ARF) has been described in lithium intoxication. We performed a systematic review of all studies pertaining to the effects of lithium on the kidney in older adults. The ARF incidence was 1.5% per person-year and concurrent loop diuretic and angiotensin-converting enzyme inhibitor use with lithium increased the risk. The CRF prevalence estimates varied from 1.2% to 34%, with risk factors including age, previous lithium intoxication, polyuria, previously impaired renal function, and decreased maximal urine osmolality. The prevalence of NDI varied widely from 1.8%  to 85%. Risk factors included lithium duration, dose, level, slow-release formulation, and clinical nonresponse. Except for amiloride use in NDI, there is little evidence for treatment of other lithium-induced adverse renal effects. Currently, there is no compelling evidence to suggest that lithium should be avoided in elderly patients for fear of renal side effects.