Drug-induced lithium toxicity in the elderly: a population-based study

Identification of Patients Who Require Two-Point Blood Sampling for the Peak and Trough Values Rather Than One-Point Blood Sampling for the Trough Value for the Evaluation of AUC of Vancomycin Using Bayesian Estimation

OBJECTIVES

It is recommended to adjust the dose of vancomycin (VCM) with a target area under the concentration-time curve (AUC) of 400-600 μg·h/mL. Factors that affect the deviation between AUCs are estimated from the trough value alone and the trough and peak values using practical AUC-guided therapeutic drug monitoring (PAT) for vancomycin. In this study, factors that affect AUC were evaluated.

METHODS

AUCs were estimated from a single trough value and trough and peak values, and the patients were classified into those who showed a 10% or greater deviation (deviation group) and those in whom the deviation was less than 10% (no-deviation group). Risk factors related to ≥ 10% deviation of AUC were identified by univariate and multivariate analysis.

RESULTS

As a result of univariate and multivariate analysis of 30 patients in the deviation group and 344 patients in the no-deviation group, a creatinine clearance (CLcr) of ≥ 110 mL/min (odds ratio (OR) = 3.697, 95% confidence interval (CI) = 1.616-8.457, p = 0.002), heart failure with a brain natriuretic peptide (BNP) of ≥ 300 pg/mL (OR = 4.854, 95%CI = 1.199-19.656, p = 0.027), and the concomitant use of angiotensin converting enzyme inhibitor or angiotensin II receptor blocker (ACE-I/ARB) (OR = 2.544, 95%CI = 1.074-6.024, p = 0.034) were identified as risk factors of ≥ 10% deviation of AUC.

CONCLUSIONS

Estimation of AUC by two-point blood sampling for the trough and peak values rather than one-point blood sampling for the trough value is suggested to improve the prediction accuracy in patients with enhanced renal function, severe heart failure, and patients using ACE-I/ARB.

Causes, clinical characteristics, and outcomes of high lithium levels and intoxications: Retrospective analysis of patient records

BACKGROUND

The mood stabilizer lithium has a narrow therapeutic index with a relevant risk of intoxication. We used real-world hospital data to identify causes, treatment courses, and outcomes of high lithium levels and intoxications.

METHODS

Retrospective chart review of patients with a lithium concentration of ⩾1.1 mmol/L, who were treated at Charité University Medical Center Berlin.

RESULTS

We identified 136 patients (58% women; mean age: 54.7 years) with high lithium levels or intoxication. 66.9% were chronic (stable lithium dose but changes in other variables such as co-medication). 40.4% took at least one risk medication with a relative contraindication for concurrent lithium treatment. 11.1% of the cases with a high therapeutic level showed moderate to severe intoxications. Feverish infections were significantly associated with severe intoxications. Overall, 97.1% (132/136) of patients fully recovered, two had residual but mild symptoms and two died during hospitalization (unlikely related to the intoxication). In 37.5% of patients, no psychiatrist was involved in the management of high lithium levels or intoxication. In these patients, lithium treatment was adjusted or discontinued in 37.3% of the cases compared to 64.7% when a psychiatrist was involved (χ²(1) = 9.683, p = 0.002).

CONCLUSIONS

Patients and medical doctors should be aware of the increased risk of lithium intoxication already within the high therapeutic range and should consider alternative medications without relative contraindications for concurrent lithium use. Involving psychiatrists during or after an intoxication event is associated with more frequent adjustment of the maintenance lithium dose and should be considered in most cases.

Quality of laboratory biomarker monitoring during treatment with lithium in patients with bipolar disorder

BACKGROUND

Clinical guidelines recommend monitoring of creatinine and lithium throughout treatment with lithium. We here assessed the extent to which this occurs in healthcare in Sweden.

METHODS

This is an observational study of all adults with bipolar disorder starting lithium therapy in Stockholm, Sweden, during 2007-2018. The main outcome was monitoring of blood lithium and creatinine at therapy initiation and/or once annually. The secondary outcome was monitoring of calcium and thyroid-stimulating hormone (TSH). Patients were followed up until therapy cessation, death, out-migration, or to the end of 2018.

RESULTS

We identified 4428 adults with bipolar disorder who started lithium therapy and were followed up for up to 11 years. Their median age was 39 years, and 63% were women. The median duration on lithium therapy was 4.3 (IQR: 1.9-7.45) years, and the majority who discontinued therapy started another mood stabilizer soon after. Overall, 21% started lithium therapy without assessing the serum/plasma concentration of creatinine. The proportion of people who did not have both lithium and creatinine measured increased from 21% in the first year to 33% in the eleventh year. The proportion with annual testing for TSH or calcium was slightly lower. As few as 16% of patients had both lithium and creatinine tested once annually during their complete time on lithium.

CONCLUSIONS

In a Swedish community sample, lithium and creatinine monitoring was inconsistent with guideline recommendations that call for measurement of annual biomarker levels.

Severe Mental Illness and Cardiovascular Disease: JACC State-of-the-Art Review

People with severe mental illness, consisting of schizophrenia, bipolar disorder, and major depression, have a high burden of modifiable cardiovascular risk behaviors and conditions and have a cardiovascular mortality rate twice that of the general population. People with acute and chronic cardiovascular disease are at a higher risk of developing mental health symptoms and disease. There is emerging evidence for shared etiological factors between severe mental illness and cardiovascular disease that includes biological, genetic, and behavioral mechanisms. This state-of-the art review will describe the relationship between severe mental illness and cardiovascular disease, explore the factors that lead to poor cardiovascular outcomes in people with severe mental illness, propose strategies to improve the cardiovascular health of people with severe mental illness, and present areas for future research focus.

A Comprehensive Review of the Pharmacologic Perspective on Loop Diuretic Drug Interactions with Therapeutically Used Drugs

Background:

Loop diuretics help to manage the patients with edema associated with congestive heart failure, liver cirrhosis, and renal disease and hypertension. The patients taking loop diuretics may receive other medications to treat comorbidities leading to drug interactions.

Methodology:

The literature was searched in databases such as Medline/PMC/PubMed, Google Scholar, Cochrane Library, Science Direct, EMBASE, Web of science, Ebsco, Directory of open access journals (DOAJ) and reference lists to spot relevant articles using the keywords Drug interactions, Pharmacodynamic interactions, Loop diuretics, Bumetanide, Ethacrynic acid, Furosemide, and Torsemide.

Results:

Loop diuretics are associated with hypokalemia, ototoxicity and other adverse effects. The drugs affected by hypokalemia, and having the potential of inducing ototoxicity could interact with loop diuretics pharmacodynamically. Loop diuretics can interact with drugs such as amphotericin B, digoxin, angiotensin-converting enzyme inhibitors (ACE inhibitors), antidiabetic drugs, antifungal agents, dobutamine, gossypoland sotalol due to diuretic associated hypokalemia. In addition, the risk of ototoxicity could be enhanced by the concomitant use of loop diuretics and cisplatin, aminoglycoside antibiotics or phosphodiesterase 5 (PDE 5) inhibitors. Loop diuretics may also interact pharmacodynamically with drugs like cephalosporins, ceritinib, levothyroxine, pixantrone, probenecid, lithium, non-steroidal anti-inflammatory drugs (NSAIDs), sulfonylureas and herbal drugs.

Conclusion:

Clinicians, pharmacists and other health care providers should take responsibility for the safe use of medications. In addition, they are required to be aware of the drugs interacting with loop diuretics, to prevent adverse drug interactions.

An Overview of Clinically Imperative and Pharmacodynamically Significant Drug Interactions of Renin-Angiotensin-Aldosterone System (RAAS) Blockers

INTRODUCTION

Hypertension is a leading cause of cardiovascular disease and chronic kidney disease, resulting in premature death and disability. The Renin-Angiotensin-Aldosterone System (RAAS) blockers, including Angiotensin-Converting Enzyme (ACE) inhibitors or Angiotensin Receptor Blockers (ARBs), are used as first-line antihypertensive therapy to treat hypertensive patients with comorbidities, including diabetes, ischemic heart disease, heart failure, and chronic kidney disease. The use of RAS blockers is associated with the risks, such as hyperkalemia, angioedema, etc. The drugs potentiating them interact pharmacodynamically, resulting in adverse consequences. This review article focuses on the clinically important drug interactions of RAAS blockers.

MATERIALS AND METHODS

The electronic databases, such as Medline/PubMed Central/PubMed, Google Scholar, ScienceDirect, Cochrane Library, Directory of Open Access Journals (DOAJ), Embase, and reference lists were searched to identify relevant articles.

RESULTS

The risk of hyperkalemia may be enhanced potentially in patients receiving a RAS blocker and potassium-sparing diuretics, potassium supplements, trimethoprim, adrenergic betablockers, antifungal agents, calcineurin inhibitors, pentamidine, heparins or an NSAID, concomitantly. The patients taking ACE inhibitors and mTOR inhibitors, DPP4 inhibitors, alteplase, or sacubitril/valsartan concurrently may be at increased risk of developing angioedema.

CONCLUSION

Clinicians, pharmacists, and other healthcare practitioners should be accountable for medication safety. To avoid adverse implications, prescribers and pharmacists must be aware of the drugs that interact with RAAS blockers.

Lithium concentration and recurrence risk during maintenance treatment of bipolar disorder: Multicenter cohort and meta-analysis

OBJECTIVE

To compare differences in efficacy during maintenance treatment for bipolar disorder (BD) according to lithium serum levels. A multicenter retrospective cohort study and a dose-response meta-analysis were conducted.

METHODS

The cohort study was conducted in Taiwan from 2001 to 2019 to identify patients with euthymic BD according to different serum levels (<0.4, 0.4-0.8, and 0.8-1.2 mmol/L). We adopted adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) for time to the recurrence of mood episodes having the <0.4 mmol/L group as the reference group. Moreover, we systematically searched for related articles in major databases before January 31, 2021 (PROSPERO: CRD42021235812). We used random-effects modeling to estimate the dose-response relationships between lithium serum levels and recurrence of mood episodes, which were depicted as odds ratios (ORs) with 95% CIs.

RESULTS

A total of 1406 participants (cohort: 466; meta-analysis: 940) were included. In the cohort study, the 0.4-0.8 mmol/L group was associated with a significantly lower risk of recurrences (aHR: 0.75), while the 0.8-1.2 mmol/L group had a lower risk without statistical significance (aHR: 0.77). The dose-response meta-analysis showed that with the increase in lithium serum levels, the risk decreased (linear model OR: 0.85, for every 0.1 mmol/L increase; non-linear model OR: 1.00 at 0.0 mmol/L, 0.42 at 0.4 mmol/L, and 0.27 at 0.8 mmol/L).

CONCLUSION

Although confounding by indication cannot be excluded, the combined results suggest a significant preventative effect on the recurrence of major affective episodes among those with serum levels of 0.4-0.8 mmol/L.

Tolerability of lithium: A naturalistic discontinuation study in older inpatients (≥60 years)

OBJECTIVES

Lithium is one of the most effective treatment options in both bipolar disorder and treatment-resistant depression. The use of lithium in older patients declined during the last decades, probably resulting in undertreatment of older patients. To investigate how well lithium is tolerated in old age, we aimed to determine the frequency, reasons, and possible predictors of discontinuation due to adverse effects in a cohort of inpatients ≥60 years who had started with lithium.

METHODS

We performed a retrospective cohort study based on chart reviews. Participants were in treatment at Parnassia Group at The Hague, The Netherlands. After inclusion (between January 2010 and December 2016), participants were followed until April 2017, when we performed data extraction and analysis.

RESULTS

In our sample of 135 patients (median age 69 years, median follow-up duration 18 months), 49 (36.3%) participants discontinued lithium. Only a minority (11 [8.1%]) of the participants discontinued solely due to adverse effects. The majority discontinued lithium due to psychiatric (18, 5%) reasons (most commonly mentioned within this subgroup: lack of effectiveness and noncompliance) or a combination of reasons (7.4%). None of the factors we studied (age, gender, Charlson Comorbidity Index, polypharmacy, renal function, and neurological history) were significantly associated with discontinuation due to adverse effects.

CONCLUSIONS

The frequency of lithium discontinuation in our cohort was in range with frequencies reported in younger patients. Older age itself should not be a reason to withhold lithium treatment.

Depression, antidepressants and fall risk: therapeutic dilemmas-a clinical review

PURPOSE

The aim of this clinical review was to summarize the existing knowledge on fall risk associated with antidepressant use in older adults, describe underlying mechanisms, and assist clinicians in decision-making with regard to (de-) prescribing antidepressants in older persons.

METHODOLOGY

We comprehensively examined the literature based on a literature search in Pubmed and Google Scholar, and identified additional relevant articles from reference lists, with an emphasis on the most commonly prescribed drugs in depression in geriatric patients. We discuss use of antidepressants, potential fall-related side effects, and deprescribing of antidepressants in older persons.

RESULTS

Untreated depression and antidepressant use both contribute to fall risk. Antidepressants are equally effective, but differ in fall-related side effect profile. They contribute to (or cause) falling through orthostatic hypotension, sedation/impaired attention, hyponatremia, movement disorder and cardiac toxicity. Falling is an important driver of morbidity and mortality and, therefore, requires prevention. If clinical condition allows, withdrawal of antidepressants is recommended in fall-prone elderly persons. An important barrier is reluctance of prescribers to deprescribe antidepressants resulting from fear of withdrawal symptoms or disease relapse/recurrence, and the level of complexity of deprescribing antidepressants in older persons with multiple comorbidities and medications. Practical resources and algorithms are available that guide and assist clinicians in deprescribing antidepressants.

CONCLUSIONS

(De-) prescribing antidepressants in fall-prone older adults is often challenging, but detailed insight in fall-related side effect profile of the different antidepressants and a recently developed expert-based decision aid STOPPFalls assists prescribers in clinical decision-making.

A double-blind, randomized, placebo-controlled pilot trial of atorvastatin for nephrogenic diabetes insipidus in lithium users

OBJECTIVE

Lithium remains an important treatment for mood disorders but is associated with kidney disease. Nephrogenic diabetes insipidus (NDI) is associated with up to 3-fold risk of incident chronic kidney disease among lithium users. There are limited randomized controlled trials (RCT) for treatments of lithium-induced NDI, and existing therapies can be poorly tolerated. Therefore, novel treatments are needed for lithium-induced NDI.

METHOD

We conducted a 12-week double-blind pilot RCT to assess the feasibility and efficacy of 20 mg/d atorvastatin vs placebo in the treatment of NDI in chronic lithium users. Patients, recruited between September 2017 and October 2018, were aged 18 to 85, currently on a stable dose of lithium, and determined to have NDI.

RESULTS

Urinary osmolality (UOsm) at 12 weeks adjusted for baseline was not statistically different between groups (+39.6 mOsm/kg [95% CI, -35.3, 114.5] in atorvastatin compared to placebo groups). Secondary outcomes of fluid intake and aquaporin-2 excretions at 12 weeks adjusted for baseline were -0.13 L [95% CI, -0.54, 0.28] and 98.68 [95% CI, -190.34, 387.70], respectively. A moderate effect size was observed for improvements in baseline UOsm by ≥100 mOsm/kg at 12 weeks in patients who received atorvastatin compared to placebo (38.45% (10/26) vs 22.58% (7/31); Cohen's d = 0.66).

CONCLUSION

Among lithium users with NDI, atorvastatin 20 mg/d did not significantly improve urinary osmolality compared to placebo over a 12-week period. Larger confirmatory trials with longer follow-up periods may help to further assess the effects of statins on NDI, especially within patients with more severe NDI.

Psychiatric Medications and Hypertension

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of psychiatric medications that impact blood pressure in adult patients either as a direct side effect or indirectly, via negative metabolic impact or interactions with other medications. In addition, pertinent interactions between psychiatric medications and antihypertensive agents will be discussed.

RECENT FINDINGS

Although the novel intranasal antidepressant, esketamine, has been shown to increase blood pressure shortly after dosing, treatment with antihypertensive medications is not typically required. In addition, no increase in serious adverse cardiac events was reported with this medication. The negative metabolic impact of antipsychotic medications has been shown to occur within the first month of treatment and necessitates early monitoring. When compared with the general population with cardiovascular disease, mortality risk in patients with severe and persistent psychiatric illness is higher, and death occurs 10 years earlier. There are several psychiatric treatments that increase blood pressure directly as well as indirectly, via negative metabolic impact and drug/diet interactions. Fortunately, there are no absolute contraindications for use of any psychiatric medication in patients with pre-existing hypertension. Given data which suggests that patients diagnosed with more severe psychiatric disorders are known to receive inadequate medical care for hypertensive illness and experience increased mortality risk from cardiovascular disease, it is important for all physicians to be aware of the increased risk in this population and for both thorough assessment and treatment to occur.

Lithium Treatment Over the Lifespan in Bipolar Disorders

Lithium has been the treatment of choice for patients with bipolar disorder (BD) for nearly 70 years. It is recommended by all relevant guidelines as a first-line treatment for maintenance therapy. In this review, we outline the current state of evidence for lithium in the treatment of BD over the lifespan. First, we summarize the evidence on efficacy in general, from relapse prevention to acute anti-manic treatment and its role in treating mood episodes with mixed features and bipolar depression. As patients are often treated for many years and different aspects have to be considered in different phases of life, we discuss the particularities of lithium in the treatment of paediatric BD, in older aged individuals and in pregnant women. Lastly, we discuss the evidence on lithium's proposed suicide-preventive effects, the dangers of rapid discontinuation and lithium's adverse effects, particularly with regard to long-term treatment.

Drug-Drug Interactions Between Lithium and Cardiovascular as Well as Anti-Inflammatory Drugs

INTRODUCTION

Lithium is the gold standard in treating bipolar affective disorders. As patients become increasingly older, drug-drug interactions leading to decreased excretion of lithium represent a key issue in lithium safety. As no study considered the effect of comedications on lithium serum concentration in combination, we aimed to quantify the impact of drugs affecting renal blood flow and function and thus potentially interacting drugs (diuretics, ACE inhibitors, AT1 antagonists, and non-steroidal anti-inflammatory drugs) on lithium serum levels in addition to age, sex, and sodium and potassium serum levels as well as renal function.

METHODS

Retrospective data of lithium serum levels were analyzed in 501 psychiatric inpatients (2008-2015) by means of linear regression modelling.

RESULTS

The number of potentially interacting drugs was significantly associated with increasing serum levels of lithium in addition to the established factors of age, renal function, and sodium concentration. Additionally, absolute lithium levels were dependent on sex, with higher values in females. However, only NSAIDs were identified to increase lithium levels independently.

DISCUSSION

Routine clinical practice needs to focus on drugs affecting renal blood flow and function, especially on NSAIDs as over-the-counter medication that may lead to an increase in lithium serum concentration. To prevent intoxications, clinicians should carefully monitor the comedications, and they should inform patients about possible intoxications due to NSAIDs.

Low-dose lithium feeding increases the SERCA2a-to-phospholamban ratio, improving SERCA function in murine left ventricles

NEW FINDINGS

What is the central question of this study? Inhibition of glycogen synthase kinase-3 (GSK3) has been shown to improve cardiac SERCA2a function. Lithium can inhibit GSK3, but therapeutic doses used in treating bipolar disorder can have toxic effects. It has not been determined whether subtherapeutic doses of lithium can improve cardiac SERCA function. What is the main finding and its importance? Using left ventricles from wild-type mice, we found that subtherapeutic lithium feeding for 6 weeks decreased GSK3 activity and increased cardiac SERCA function compared with control-fed mice. These findings warrant the investigation of low-dose lithium feeding in preclinical models of cardiomyopathy and heart failure to determine the therapeutic benefit of GSK3 inhibition.

ABSTRACT

The sarco(endo)plasmic reticulum Ca²⁺ -ATPase (SERCA) pump is responsible for regulating calcium (Ca²⁺ ) within myocytes, with SERCA2a being the dominant isoform in cardiomyocytes. Its inhibitor, phospholamban (PLN), acts by decreasing the affinity of SERCA for Ca²⁺ . Changes in the SERCA2a:PLN ratio can cause Ca²⁺ dysregulation often seen in patients with dilated cardiomyopathy and heart failure. The enzyme glycogen synthase kinase-3 (GSK3) is known to downregulate SERCA function by decreasing the SERCA2a:PLN ratio. In this study, we sought to determine whether feeding mice low-dose lithium, a natural GSK3 inhibitor, would improve left ventricular SERCA function by altering the SERCA2a:PLN ratio. To this end, male wild-type C57BL/6J mice were fed low-dose lithium via drinking water (10 mg kg^-1  day^-1 LiCl for 6 weeks) and left ventricles were harvested. GSK3 activity was significantly reduced in LiCl-fed versus control-fed mice. The apparent affinity of SERCA for Ca²⁺ was also increased (pCa₅₀ ; control, 6.09 ± 0.03 versus LiCl, 6.26 ± 0.04, P < 0.0001) along with a 2.0-fold increase in SERCA2a:PLN ratio in LiCl-fed versus control-fed mice. These findings suggest that low-dose lithium supplementation can improve SERCA function by increasing the SERCA2a:PLN ratio. Future studies in murine preclinical models will determine whether GSK3 inhibition via low-dose lithium could be a potential therapeutic strategy for dilated cardiomyopathy and heart failure.

The Combination of Lithium and ACE Inhibitors: Hazardous, Critical, Possible?

Lithium is a well established therapeutic agent in the treatment of uni- and bipolar affective disorders. Angiotensin-converting enzyme (ACE) inhibitors are the most frequently used class of drugs in the treatment of cardiovascular diseases. Combination therapy with both may be considered in clinical practice on occurrence of arterial hypertension after years of successful lithium therapy, yet an increased risk of lithium intoxication in combination with ACE inhibitors has been described and thus the combination has been warned against. We describe three cases in which enalapril, lisinopril or ramipril was combined with lithium. Either additional co-medication with hydrochlorothiazide or dehydration rather than co-medication with ACE inhibitors could be identified as necessary factors for lithium intoxication. These cases suggest that a combination of lithium with ACE inhibitors is possible when sufficient hydration is ensured and a combination with hydrochlorothiazide is avoided. Lithium concentration should be controlled on a regular level.

Using Lithium in Older Age Bipolar Disorder: Special Considerations

Lithium is the gold-standard treatment for bipolar disorder, and is effective in the management of manic, depressive, and maintenance phases of bipolar disorder treatment. Despite this, the implications of lithium use in the older population remain less understood. This critical narrative review aims to better understand the impact of lithium in older age bipolar disorder (OABD), including tolerability and efficacy, based on up-to-date evidence. Relevant studies of efficacy, effectiveness, and tolerability published any time prior to May 2018 were identified using the PubMed keyword search "lithium older adult bipolar disorder" and references from recent international bipolar disorder guidelines. One randomized controlled trial was identified, the GERI-BD (Acute Pharmacotherapy in Late-Life Mania) study. This study found lithium to be effective in late-life mania and hypomania. The remaining literature examining lithium in OABD was reviewed, comprising of a number of small open-label and retrospective studies, with special considerations highlighted. In summary, there is a small yet increasing geriatric evidence base that lithium is effective in OABD. Although there can be adverse effects with lithium, it is generally well tolerated, and there are methods to minimize these risks. Further research would strengthen the evidence base for lithium therapy in OABD. In the meantime, lithium remains the gold-standard treatment for OABD.

Delphi survey of maintenance lithium treatment in older adults with bipolar disorder: An ISBD task force report

OBJECTIVES

Despite the growing numbers and proportion of older adults with bipolar disorder (OABD), there are very limited guidelines for the use of lithium with its double-edged potential for effectiveness and toxicity in this population. The primary aims of this Delphi survey were: (a) To determine the place of lithium among the preferred choices for maintenance treatment of OABD. (b) To provide detailed clinical guidelines for the safe and effective use of lithium in OABD.

METHODS

In the face of limited evidence, the Delphi survey method was used to achieve consensus by a group of 25 experts in OABD from nine countries. An oversight committee monitored and analyzed the results of each survey and formulated more focused questions with each subsequent iteration.

RESULTS

A 100% response rate was achieved for all three iterations of the survey. Lithium was the preferred choice for maintenance monotherapy in OABD. Serum levels of 0.4-0.8 mmol/L were recommended for ages 60-79 and serum levels of 0.4-0.7 mmol/L were recommended for ages 80 and over. Specific recommendations achieved consensus for second line monotherapy as well as for other drugs to be used in combination with lithium if necessary. Guidelines for routine monitoring of lithium in OABD were provided for laboratory investigations and clinical assessments.

CONCLUSIONS

Lithium remains the preferred choice for maintenance monotherapy in OABD. Laboratories should report the therapeutic range for serum levels of lithium separately for older adults.

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.

Atorvastatin in the treatment of Lithium-induced nephrogenic diabetes insipidus: the protocol of a randomized controlled trial

BACKGROUND

Lithium is the gold-standard treatment for bipolar disorder, is highly effective in treating major depressive disorder, and has anti-suicidal properties. However, clinicians are increasingly avoiding lithium largely due to fears of renal toxicity. Nephrogenic Diabetes Insipidus (NDI) occurs in 15-20% of lithium users and predicts a 2-3 times increased risk of chronic kidney disease (CKD). We recently found that use of statins is associated with lower NDI risk in a cross-sectional study. In this current paper, we describe the methodology of a randomized controlled trial (RCT) to treat lithium-induced NDI using atorvastatin.

METHODS

We will conduct a 12-week, double-blind placebo-controlled RCT of atorvastatin for lithium-induced NDI at McGill University, Montreal, Canada. We will recruit 60 current lithium users, aged 18-85, who have indicators of NDI, which we defined as urine osmolality (UOsm) < 600 mOsm/kg after 10-h fluid restriction. We will randomize patients to atorvastatin (20 mg/day) or placebo for 12 weeks. We will examine whether this improves measures of NDI: UOsm and aquaporin (AQP2) excretion at 12-week follow-up, adjusted for baseline.

RESULTS

Not applicable.

CONCLUSION

The aim of this clinical trial is to provide preliminary data about the efficacy of atorvastatin in treating NDI. If successful, lithium could theoretically be used more safely in patients with a reduced subsequent risk of CKD, hypernatremia, and acute kidney injury (AKI). If future definitive trials confirm this, this could potentially allow more patients to benefit from lithium, while minimizing renal risk.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02967653 . Registered in February 2017.

Lithium Intoxication: A Possible Interaction with Moxifloxacin

Lithium is a well-known treatment for patients with mood disorders. Intoxication by lithium may be lethal particularly in elderly due to altered pharmacokinetics, renal impairment or multiple drug use. We presented a 74-year-old female patient who had been stabile with lithium carbonate 600 mg/day for 5 years and developed lithium intoxication after bronchiolitis. She presented with altered mental status. The neurological signs resolved slowly after lithium and moxifloxacin were stopped immediately and fluid resuscitation administered. Considering possible drug interactions on elderly patients receiving lithium is essential.

Drug Interactions with Lithium: An Update

Lithium has been used for the management of psychiatric illnesses for over 50 years and it continues to be regarded as a first-line agent for the treatment and prevention of bipolar disorder. Lithium possesses a narrow therapeutic index and comparatively minor alterations in plasma concentrations can have significant clinical sequelae. Several drug classes have been implicated in the development of lithium toxicity over the years, including diuretics and non-steroidal anti-inflammatory compounds, but much of the anecdotal and experimental evidence supporting these interactions is dated, and many newer medications and medication classes have been introduced during the intervening years. This review is intended to provide an update on the accumulated evidence documenting potential interactions with lithium, with a focus on pharmacokinetic insights gained within the last two decades. The clinical relevance and ramifications of these interactions are discussed.

Hypertensive bipolar: chronic lithium toxicity in patients taking ACE inhibitor

A patient with bipolar I disorder has been treated with lithium and haloperidol for the last 20 years and received an ACE inhibitor for his hypertension since 9 years ago. Despite regular clinic follow-ups and blood monitoring, he recently developed tremors and delirium. On hospital admission, serum level of lithium was far above toxic level. Mental state examination revealed an anxious and disorientated man with irrelevant speech. Immediate discontinuation of lithium resulted in slow reduction of serum lithium levels and gradual resolution of tremor but his delirium persisted for 2 weeks. His condition took a turn for the worse when he developed acute renal failure and arm abscess. We discussed about lithium toxicity and the vulnerability factors which have induced delirium and renal failure in this patient.

Global Research Trends in Lithium Toxicity from 1913 to 2015: A Bibliometric Analysis

Lithium salts have been used to treat psychiatric disorders since the 1940s and are currently used in prophylaxis and treatment of depression and bipolar disorder. Therefore, we conducted this study to assess lithium toxicity-related publications using bibliometric approaches from a health point of view to assess global research trends in the lithium toxicity field to offer guidance to future research in this field. The data were retrieved from the online version of Scopus database on 6 August 2016. All records with the term 'lithium' in the title were retrieved, and those related to lithium toxicity were evaluated. There were a total of 1241 publications related to lithium toxicity published from 1913 to 2016. Articles (971 or 78.2%) were the most common type, followed by letters (179 or 14.4%) and reviews (61 or 4.9%). The annual publication of articles increased slightly after 1950 and the total number of publications related to lithium toxicity fluctuated with three peaks occurred in 1978, 1985 and 2014. The USA was the predominant country (25.38%), followed by the UK (7.82%), France (6.85%) and Canada (3.55%). Denmark had the highest productivity of publication after standardization by gross domestic product and population size. The average number of citations per article was 9.24, and the h-index for all publications in the field of lithium toxicity was 46. The highest h-index value was achieved by the USA (31) followed by the UK (21) and Canada (13). The Lancet was the highest ranked journal with 27 articles, followed by American Journal of Psychiatry with 23 articles. This study provides a bibliometric analysis on the global research trends in lithium toxicity studies during 1913-2015. There has been a progressive increase in the number of publications related to lithium toxicity published in the last decade, and most of the studies related to lithium toxicity arose from the USA and the UK.

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.

Lithium Poisoning

Lithium is a commonly prescribed treatment for bipolar affective disorder. However, treatment is complicated by lithium’s narrow therapeutic index and the influence of kidney function, both of which increase the risk of toxicity. Therefore, careful attention to dosing, monitoring, and titration is required. The cause of lithium poisoning influences treatment and 3 patterns are described: acute, acute-on-chronic, and chronic. Chronic poisoning is the most common etiology, is usually unintentional, and results from lithium intake exceeding elimination. This is most commonly due to impaired kidney function caused by volume depletion from lithium-induced nephrogenic diabetes insipidus or intercurrent illnesses and is also drug-induced. Lithium poisoning can affect multiple organs; however, the primary site of toxicity is the central nervous system and clinical manifestations vary from asymptomatic supratherapeutic drug concentrations to clinical toxicity such as confusion, ataxia, or seizures. Lithium poisoning has a low mortality rate; however, chronic lithium poisoning can require a prolonged hospital length of stay from impaired mobility and cognition and associated nosocomial complications. Persistent neurological deficits, in particular cerebellar, are described and the incidence and risk factors for its development are poorly understood, but it appears to be uncommon in uncomplicated acute poisoning. Lithium is readily dialyzable, and rationale support extracorporeal treatments to reduce the risk or the duration of toxicity in high-risk exposures. There is disagreement in the literature regarding factors that define patients most likely to benefit from treatments that enhance lithium elimination, including specific plasma lithium concentration thresholds. In the case of extracorporeal treatments, there are observational data in its favor, without evidence from randomized controlled trials (none have been performed), which may lead to conservative practices and potentially unnecessary interventions in some circumstances. More data are required to define the risk–benefit of extracorporeal treatments and their use (modality, duration) in the management of lithium poisoning.

General pharmacokinetic/pharmacodynamic concepts of mood stabilizers in the treatment of bipolar disorder

Introduction:

Mood stabilizers are the recommended treatment for patients who receive a diagnosis of bipolar disorder. Because of the necessity of mood stabilizer treatment in patients with bipolar disorder and the extent of pharmacokinetic and pharmacodynamic principles involved, the purpose of this review is to summarize the pharmacokinetic principles of lithium in addition to the pharmacodynamics of lithium, carbamazepine, lamotrigine, and valproic acid/valproate.

Methods:

Practice guidelines, review articles, and clinical trials were located using online databases PubMed, CINAHL, IDIS, and Medline. Search terms included at least one of the following: bipolar disorder, carbamazepine, lamotrigine, lithium, mood stabilizers, pharmacokinetics, pharmacodynamics, valproate, and valproic acid. Online clinical databases Dynamed® and Lexicomp® were also used in the study.

Results:

Mood stabilizers collectively possess distinct qualities that are closely regarded before, during, and after therapeutic initiation. Individual patient characteristics, coupled with these observed traits, add to the complexity of selecting the most optimal neurologic agent. Each medication discussed uniquely contributes to both the maintenance and restoration of overall patient well-being.

Discussion:

Introduction of mood stabilizers into drug regimens is often done in the presence of an array of mitigating factors. Safety and efficacy measures are commonly used to gauge desired results. Careful monitoring of patients' responses to selected therapies is paramount for arriving at appropriate clinical outcomes.

Creating a 'reverse' integrated primary and mental healthcare clinic for those with serious mental illness

Individuals with serious mental illness (SMI) are more likely to experience preventable medical health issues, such as diabetes, hyperlipidemia, obesity, and cardiovascular disease, than the general population. To further compound this issue, these individuals are less likely to seek preventative medical care. These factors result in higher usage of expensive emergency care, lower quality of care, and lower life expectancy. This manuscript presents literature that examines the health disparities this population experiences, and barriers to accessing primary care. Through the identification of these barriers, we recommend that the field of family medicine work in collaboration with the field of mental health to implement 'reverse' integrated care (RIC) systems, and provide primary care services in the mental health settings. By embedding primary care practitioners in mental health settings, where individuals with SMI are more likely to present for treatment, this population may receive treatment for somatic care by experts. This not only would improve the quality of care received by patients, but would also remove the burden of managing complex somatic care from providers trained in mental health. The rationale for this RIC system, as well as training and policy reforms, are discussed.

Hemodialysis for lithium poisoning

BACKGROUND

Lithium salts, particularly lithium carbonate, are frequently used to treat bipolar disorder and mania. Lithium poisoning, which can occur as a result of reduced renal elimination, prescribing error, drug-drug interactions, or deliberate overdosage, produces neurologic injury that can be permanent. Hemodialysis is often recommended to treat lithium poisoning. Although hemodialysis clearly enhances the elimination of lithium, it is unclear whether this translates into improved patient outcomes. Evidence from observational studies, generally of low methodological quality, shows similar outcomes in patients managed with or without the use of hemodialysis.

OBJECTIVES

To determine whether hemodialysis, applied in addition to standard therapy, reduces the likelihood, severity, or duration of neurological sequelae following lithium poisoning.

SEARCH METHODS

We ran the search on 15 May 2015. We searched the Cochrane Injuries Group's Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE (OvidSP), Embase Classic+Embase (OvidSP), CINAHL Plus, clinical trials registers and four other databases. We screened the reference lists of relevant studies, textbook chapters, and review articles, and performed a Google search to identify grey literature.

SELECTION CRITERIA

In the context of this review, hemodialysis was defined as any extracorporeal technique to filter and extract toxicants from the serum, including all forms of hemodialysis, hemofiltration, and continuous renal replacement techniques, but not peritoneal dialysis. We included any clinical trials in which patients were randomly allocated to receive, or not receive, hemodialysis in addition to standard care for lithium poisoning.

DATA COLLECTION AND ANALYSIS

Two authors reviewed the abstracts of all identified articles. If either author identified an article as potentially meeting the inclusion criteria, both authors reviewed the full text of the article.

MAIN RESULTS

No randomized controlled trials of hemodialysis therapy for lithium poisoning were identified.

AUTHORS' CONCLUSIONS

Although the use of hemodialysis to enhance the elimination of lithium in patients with lithium poisoning appears logical, there is no evidence from randomized controlled trials to support nor refute the use of hemodialysis in the management of patients with lithium poisoning.

Pathophysiology, diagnosis and management of nephrogenic diabetes insipidus

Healthy kidneys maintain fluid and electrolyte homoeostasis by adjusting urine volume and composition according to physiological needs. The final urine composition is determined in the last tubular segment: the collecting duct. Water permeability in the collecting duct is regulated by arginine vasopressin (AVP). Secretion of AVP from the neurohypophysis is regulated by a complex signalling network that involves osmosensors, barosensors and volume sensors. AVP facilitates aquaporin (AQP)-mediated water reabsorption via activation of the vasopressin V2 receptor (AVPR2) in the collecting duct, thus enabling concentration of urine. In nephrogenic diabetes insipidus (NDI), inability of the kidneys to respond to AVP results in functional AQP deficiency. Consequently, affected patients have constant diuresis, resulting in large volumes of dilute urine. Primary forms of NDI result from mutations in the genes that encode the key proteins AVPR2 and AQP2, whereas secondary forms are associated with biochemical abnormalities, obstructive uropathy or the use of certain medications, particularly lithium. Treatment of the disease is informed by identification of the underlying cause. Here we review the clinical aspects and diagnosis of NDI, the various aetiologies, current treatment options and potential future developments.

Appropriate prescribing in the elderly: Current perspectives

Advances in medical therapeutics have undoubtedly contributed to health gains and increases in life expectancy over the last century. However, there is growing evidence to suggest that therapeutic decisions in older patients are frequently suboptimal or potentially inappropriate and often result in negative outcomes such as adverse drug events, hospitalisation and increased healthcare resource utilisation. Several factors influence the appropriateness of medication selection in older patients including age-related changes in pharmacokinetics and pharmacodynamics, high numbers of concurrent medications, functional status and burden of co-morbid illness. With ever-increasing therapeutic options, escalating proportions of older patients worldwide, and varying degrees of prescriber education in geriatric pharmacotherapy, strategies to assist physicians in choosing appropriate pharmacotherapy for older patients may be helpful. In this paper, we describe important age-related pharmacological changes as well as the principal domains of prescribing appropriateness in older people. We highlight common examples of drug-drug and drug-disease interactions in older people. We present a clinical case in which the appropriateness of prescription medications is reviewed and corrective strategies suggested. We also discuss various approaches to optimising prescribing appropriateness in this population including the use of explicit and implicit prescribing appropriateness criteria, comprehensive geriatric assessment, clinical pharmacist review, prescriber education and computerized decision support tools.

Prevalence and correlates of renal disease in older lithium users: a population-based study

OBJECTIVE

Lithium is an important treatment for mood disorders, but concern about its association with renal disease has contributed to its limited use, particularly in older adults. Because high-quality evidence examining renal disease in this population is lacking, this study aims to quantify the prevalence and identify clinical correlates of renal disease in geriatric lithium users.

METHODS

In a population-based cross-sectional study on 2,480 lithium users aged 70 or more years, the authors searched the provincial administrative health data from Ontario, Canada between April 1, 2005 and March 31, 2011. Prevalence of chronic kidney disease (CKD), acute kidney injury (AKI), and nephrogenic diabetes insipidus (NDI) was measured using International Classification of Diseases, Tenth Revision codes. Logistic regression analyses were used to identify independent correlates of renal disease.

RESULTS

The 6-year prevalence rates of CKD, AKI, and NDI were 13.9%, 1.3%, and 3.0%, respectively. Hypertension (odds ratio [OR]: 2.05; 95% confidence interval [CI]: 1.50-2.79), diabetes mellitus (OR: 1.86; 95% CI: 1.45-2.38), ischemic heart disease (OR: 1.65; 95% CI: 1.24-2.20), NDI (OR: 2.54; 95% CI: 1.47-4.40), AKI (OR: 11.7; 95% CI: 5.26-26.1), lithium use for more than 2 years (OR: 1.71; 95% CI: 1.05-2.81), loop diuretic use (OR: 1.74; 95% CI: 1.26-2.41), hydrochlorothiazide use (OR: 1.48; 95% CI: 1.07-2.05), and atypical antipsychotic use (OR: 1.49; 95% CI: 1.17-1.89) were all independently associated with CKD.

CONCLUSION

Older lithium users have high rates of CKD. Lithium use duration was independently associated with CKD. Longitudinal studies including individuals without lithium exposure will be necessary to confirm whether lithium is indeed a risk factor for CKD in older adults.

Renal function in geriatric psychiatry patients compared to non-psychiatric older adults: effects of lithium use and other factors

OBJECTIVES

Chronic renal failure is very common, affecting 30%-40% of community-dwelling elderly. We wished to verify whether geriatric psychiatry patients are at increased risk of renal dysfunction compared to elderly controls, as well as whether lithium exposure and other factors are important predictors of risk.

METHOD

This is a four-year retrospective cohort and nested case-control study at a Canadian tertiary-care hospital using data from March 2007 to March 2011. We compared 82 geriatric psychiatry outpatients and 200 psychotropic-naïve family medicine controls aged ≥65. Our main continuous measure of renal outcome was change in estimated glomerular filtration rate (eGFR). Multivariate analyses were performed to determine potential risk factors for renal dysfunction in geriatric psychiatry patients, including age, hypertension, diabetes mellitus, diuretics, and lithium duration.

RESULTS

Clinically important decreases in eGFR (>8 mL/min/1.73 m(2)) were found in 40.2% of geriatric psychiatry patients compared to 29.5% of controls (p = 0.040). Multivariate analyses found that lithium duration was independently associated with adverse renal outcome in patients with eGFR < 60 mL/min/1.73 m(2). In this sub-population, lithium users had clinically important decreases in eGFR when compared to non-lithium users: 10.3 vs. 0.40 mL/min/1.73 m(2) (p = 0.017).

CONCLUSION

Geriatric psychiatry patients are at a greater risk for clinically important decreases of renal function than similarly aged controls. Lithium appears to be an important risk factor for renal dysfunction when eGFR is <60 mL/min/1.73 m(2). However, in the majority of older adults who have normal kidney function, lithium use appears to be safe.

Temporal association as a prerequisite factor of valsartan-induced lithium toxicity

OBJECTIVES

Lithium is often the mood stabilizer of choice for the treatment of type I bipolar disorder. However, side effects as well as the narrow therapeutic dosing range often complicate its use. Lithium toxicity can be fatal and its serum level needs to be closely monitored, especially at the time of introduction and titration, or whenever combined with potentially interacting drugs, such as inhibitors of angiotensin-converting enzyme (ACE-I) or angiotensin receptor 1 (AT1 ) blockers. ACE-I and AT1 blockers can increase serum lithium levels, leading to acute lithium toxicity upon their introduction or titration.

METHODS

Here, we report a case of lithium toxicity during concomitant treatment with valsartan, an AT1 blocker, in a patient who previously displayed a stable serum lithium level. The patient was observed for a few weeks and the serum lithium concentration was measured regularly.

RESULTS

In contrast to previous reports, the toxicity in our patient occurred not upon introduction or titration of lithium or valsartan but after subtle modifications in daily dosing schedule for lithium. Just before the onset of toxicity, lithium had been split into two doses, whereby half of the lithium daily dose was administrated concomitantly with valsartan. We presumed that this combination had led to simultaneous concentration peaks of valsartan and lithium, promoting lithium retention within a sharp time window.

CONCLUSIONS

Our observation points to the need for caution not only during the introduction and titration of ACE-I/AT1 blockers in lithium-treated patients, but also whenever the temporal pattern of drug administration is modified.

The McGill Geriatric Lithium-Induced Diabetes Insipidus Clinical Study (McGLIDICS)

OBJECTIVE

Despite being a common and potentially serious condition, nephrogenic diabetes insipidus (NDI) remains poorly understood in older lithium users. Our main objective was to compare the prevalence of NDI symptoms and decreased urine osmolality ([UOsm] < 300 milli-Osmoles [mOsm/kg]) among geriatric and adult lithium users. We also assessed NDI symptoms, serum sodium (Na+), and urine specific gravity (USG) as possible surrogate measures of decreased UOsm, and ascertained whether potential etiologic factors independently correlated with decreased UOsm.

METHOD

This was a cross-sectional study of 100 consecutive outpatients treated with lithium from 6 tertiary care clinics, of which 45 were geriatric (aged 65 years and older) and 55 adult (aged 18 to 64 years). Patients completed a symptom questionnaire and underwent laboratory tests, including UOsm, serum Na+, and USG.

RESULTS

Geriatric and adult lithium users had similar rates of decreased UOsm (12.5%, compared with 17.9%, P = 0.74), but geriatric patients reported less symptoms (P < 0.05). Although UOsm did not correlate with symptoms or current serum Na+, USG of less than 1.010 was suggestive of UOsm of less than 300 mOsm/kg. Age, lithium duration, and serum lithium level were independently associated with UOsm.

CONCLUSIONS

The prevalence of decreased UOsm is similar in geriatric and adult lithium users, but older patients are less likely to report urinary and thirst symptoms. Although subjective symptoms do not correlate with UOsm, USG may be a cost-efficient clinical surrogate measure for UOsm. We suggest clinicians increase their vigilance for decreased UOsm, especially in lithium users with advanced age, longer duration of lithium exposure, and higher lithium levels. This may potentially prevent lithium intoxication, falls, hypernatremic events, and renal dysfunction.

Monitoring lithium therapy: the impact of a quality improvement programme in the UK

OBJECTIVES

The study was designed to test an audit-based quality improvement programme (QIP) addressing lithium prescribing and monitoring in UK mental health services.

METHODS

A baseline clinical audit was conducted against the following standards: (i) measurement of renal and thyroid function before initiating treatment with lithium and (ii) recommended monitoring of serum lithium and renal and thyroid function during maintenance treatment. A re-audit was conducted at 18 months and a supplementary audit at three years.

RESULTS

Data were submitted for patients at baseline (n = 3,373), re-audit (n = 3,647), and supplementary audit (n = 5,683), 57% of whom had bipolar disorder. The baseline findings prompted a patient safety alert issued by the National Patient Safety Agency. By supplementary audit, the proportion of patients having four serum lithium tests over the previous year had increased from 30% at baseline to 48%, and the respective proportions that had two tests of renal function from 55% to 70% and thyroid function from 49% to 66%. Elderly patients and those prescribed a drug known to interact with lithium were not more likely to be monitored in line with the audit standards. Between baseline and supplementary audit, the proportion of patients with a diagnosis of bipolar disorder prescribed an antidepressant increased from 36% to 41%.

CONCLUSIONS

Improvements in biochemical monitoring of lithium treatment were achieved over time with participation in a QIP that included benchmarking of performance against clinical standards and customized change interventions. Nevertheless, gaps remain between the standard and current practice. Antidepressants are frequently prescribed in patients with bipolar disorder despite a paucity of evidence supporting their efficacy.

Adverse drug events as a cause of hospitalization in older adults

Older adults are about four to seven times more likely than younger persons to experience adverse drug events (ADEs) that cause hospitalization, especially if they are women and take multiple medications. The prevalence of drug-related hospitalizations has been reported to be as high as 31%, with large heterogeneity between different studies, depending on study setting (all hospital admissions or only acute hospital admissions), study population (entire hospital, specific wards, selected population and/or age groups), type of drug-related problem measured (adverse drug reaction or ADE), method of data collection (chart review, spontaneous reporting or database research) and method and definition used to detect ADEs. The higher risk of drug-related hospitalizations in older adults is mainly caused by age-related pharmacokinetic and pharmacodynamic changes, a higher number of chronic conditions and polypharmacy, which is often associated with the use of potentially inappropriate drugs. Other factors that have been involved are errors related to prescription or administration of drugs, medication non-adherence and inadequate monitoring of pharmacological therapies. A few commonly used drugs are responsible for the majority of emergency hospitalizations in older subjects, i.e. warfarin, oral antiplatelet agents, insulin and oral hypoglycaemic agents, central nervous system agents. The aims of the present review are to summarize recent evidence concerning drug-related hospitalization in older adults, to assess the contribution of specific medications, and to identify potential interventions able to reduce the occurrence of these drug-related events, as they are, at least partly, potentially preventable.

Prolonged peripheral nerve blockade in patients using lithium carbonate

Peripheral nerve blocks with local anaesthesia are routinely utilized in oral surgical procedures to achieve anaesthesia at the operative site. A number of local tissue factors as well as systemic conditions and medications may alter the onset, depth and duration of peripheral nerve blocks. This article describes two cases of extremely prolonged anaesthesia in patients treated with chronic oral lithium carbonate who had been administered inferior alveolar, lingual, long buccal, greater palatine and posterior superior alveolar nerve blocks with lidocaine with adrenaline for surgical removal of an upper and a lower third molar tooth. A possible relation with systemic lithium therapy and its probable mode of action are explored.

Age as a determinant of instability of serum lithium concentrations

BACKGROUND

Lithium is used both in bipolar disorder and as augmentation in treatment-resistant unipolar depression. Long-term treatment is often indicated. Pharmacokinetic and pharmacodynamic changes in older age, as well as increasing comorbidities and polypharmacy, could result in instability of serum lithium concentrations. In this study, several parameters, considered proxy for instability, were compared between age groups. These parameters were derived from studies involving oral anticoagulants.

METHODS

A retrospective study (1995-2004) was conducted using serum lithium concentrations from the laboratories of 3 hospitals in the Netherlands; 759 patients treated with lithium, 40 years or older, with at least 2 years' follow-up were identified. They were divided into 4 age groups: 40-49, 50-59, 60-69, and 70+ years; the youngest group was used as a reference group. The variance growth rate and percentage of time below, in, and above treatment range are all proxies for instability. They were analyzed between the age categories.

RESULTS

There was no significant difference for these variables between the reference group and the older age groups. In a subgroup of 454 patients, the parameters considered as proxy for instability during titration, number of days and number of serum lithium concentration measurements during titration, were evaluated; no significant difference was found between the age groups. In a small group of 117 patients, titration and maintenance treatment for at least 2 years could be analyzed separately. Also in this group, there was no difference between the age groups.

CONCLUSIONS

Age is not a determinant of serum lithium concentration instability. Therefore, age is not a reason to not initiate or discontinue lithium therapy.