Meta-analysis of the effects of lithium usage on serum creatinine levels

Psychotropic Drugs and Adverse Kidney Effects: A Systematic Review of the Past Decade of Research

BACKGROUND AND OBJECTIVE

Psychotropic drugs are a heterogenous group of treatments prescribed for many psychiatric disorders, often for long periods. Their effects on the kidney and its functioning are complex and a source of significant research and debate. This article aims to review recent evidence of the acute and chronic kidney adverse events of diverse psychotropes.

METHODS

A systematic search of randomized controlled trials and large observational studies (n ≥ 100) reporting the effects of psychotropic drugs on the kidney was conducted. The MEDLINE, PsycInfo, and EMBASE databases from 2011 to 2021, inclusive, were broadly searched with few restrictions and no prespecified outcomes. Two or more independent reviewers assessed and summarized all eligible studies, including risks of bias and levels of evidence.

RESULTS

In all, 1999 abstracts were screened for eligibility and 47 articles were included, which examined lithium (33), antiepileptics (10), antipsychotics (13), and antidepressants (9). No studies examining kidney adverse effects of other psychotropes, such as benzodiazepines, met inclusion criteria. Study populations were adult (8), geriatric (9), and mixed (30). Lithium was almost unanimously associated with (1) chronic kidney disease and (2) nephrogenic diabetes insipidus in methodologically diverse studies. The most supported risk factors for declining kidney functioning with lithium were advanced age, duration of lithium treatment, acute lithium toxicity, female sex, medications with known renal interactions, diabetes mellitus/hyperglycemia, and overall medical comorbidity. Supratherapeutic lithium concentrations are both the causes and consequences of acute kidney injury. Once significant chronic kidney disease has developed, four studies found that replacing lithium with other mood stabilizers does not slow progression, and the evolution to end-stage kidney disease is rare overall with modern practices. Compared to lithium, fewer studies examined antipsychotics and antiepileptics but found relatively less direct kidney harms. Antidepressants were not associated with acute or chronic kidney harms.

CONCLUSIONS

Despite the heterogeneity of findings, owing to varying methodologies and research challenges, recent studies strongly suggest that lithium is associated with an increased risk of chronic kidney disease and nephrogenic diabetes insipidus, especially in older adults and long-term lithium users. Clinicians should balance the harms of lithium against its established benefits, and ensure adequate monitoring and management of comorbidities in all patients. Weaker evidence suggests that antiepileptics such as valproate and antipsychotics result in comparatively less harm to the kidney than lithium, but warrant monitoring because of multiple direct and indirect mechanisms for potential kidney adverse events. Antidepressants do not have clear kidney adverse effects and appear safe (though potentially less effective) in the setting of kidney disease. Other classes of psychotropic drugs have received little research interest. Further research is warranted, particularly into specific antiepileptics and antipsychotics, and careful attention should be paid to mitigating important sources of bias such as confounding by indication.

Safety and Efficacy of Combined Low-Dose Lithium and Low-Dose Aspirin: A Pharmacological and Behavioral Proof-of-Concept Study in Rats

Despite established efficacy in bipolar disorder patients, lithium (Li) therapy has serious side effects, particularly chronic kidney disease. We examined the safety and behavioral effects of combined chronic low-dose aspirin plus low-dose Li in rats to explore the toxicity and therapeutic potential of this treatment. Rats were fed regular or Li-containing food (0.1% [low-dose, LLD-Li] or 0.2% [standard-dose, STD-Li]) for six weeks. Low-dose aspirin (1 mg/kg) was administered alone or together with Li. Renal function and gastric mucosal integrity were assessed. The effects of the combination treatment were evaluated in depression-like and anxiety-like behavioral models. Co-treatment with aspirin did not alter plasma Li levels. Chronic STD-Li treatment resulted in significant polyuria and polydipsia, elevated blood levels of creatinine and cystatin C, and increased levels of kidney nephrin and podocin—all suggestive of impaired renal function. Aspirin co-treatment significantly damped STD-Li-induced impairments in kidney parameters. There were no gastric ulcers or blood loss in any treatment group. Combined aspirin and LLD-Li resulted in a significant increase in sucrose consumption, and in the time spent in the open arms of an elevated plus-maze compared with the LLD-Li only group, suggestive of antidepressant-like and anxiolytic-like effects, respectively. Thus, we demonstrate that low-dose aspirin mitigated the typical renal side effects of STD-Li dose and enhanced the beneficial behavioral effects of LLD-Li therapy without aggravating its toxicity.

Plasma Lithium Levels in a General Population: A Cross-Sectional Analysis of Metabolic and Dietary Correlates

Initial evidence suggests that lithium might affect life expectancy and the risk for different disease conditions, but most studies were conducted in patients on lithium medication. Little is known about the association of blood lithium levels within the physiological range with cardiometabolic risk factors and diet. We measured plasma lithium in a community-based sample from Northern Germany (samples taken between 2010 and 2012). All participants (aged 25-82 years) underwent standardized examinations and completed a semi-quantitative food frequency questionnaire. Of several variables tested, the estimated glomerular filtration rate (eGFR) was statistically significantly (inversely) associated with lithium levels, mainly in individuals with slightly impaired renal function (eGFR < 75 mL/min/1.73 m²). Besides, lithium levels were positively associated with age and alcohol intake. Using reduced rank regression, we identified a dietary pattern explaining 8.63% variation in plasma lithium levels. Higher lithium levels were associated with higher intakes of potatoes, leafy vegetables, root vegetables, fruits, tea, beer, wine and dietetic products and lower intakes of pasta, rice, pork, chocolate, sweets, soft drinks, other alcoholic beverages, sauces and snacks. Our observations suggest that plasma lithium levels are associated inversely with kidney function, particularly in individuals with slightly impaired renal function, and positively with age and alcohol intake. Lithium at physiological levels was moderately related to an exploratory dietary pattern.

Systematic review and practical guideline for the prevention and management of the renal side effects of lithium therapy

Lithium is the first line therapy of bipolar mood disorder. Lithium-induced nephrogenic diabetes insipidus (Li-NDI) and lithium nephropathy (Li-NP, i.e., renal insufficiency) are prevalent side effects of lithium therapy, with significant morbidity. The objective of this systematic review is to provide an overview of preventive and management strategies for Li-NDI and Li-NP. For this, the PRISMA guideline for systematic reviews was used. Papers on the prevention and/or treatment of Li-NDI or Li-NP, and (influenceable) risk factors for development of Li-NDI or Li-NP were included. We found that the amount of evidence on prevention and treatment of Li-NDI and Li-NP is scarce. To prevent Li-NDI and Li-NP we advise to use a once-daily dosing schedule, target the lowest serum lithium level that is effective and prevent lithium intoxication. We emphasize the importance of monitoring for Li-NDI and Li-NP, as early diagnosis and treatment can prevent further progression and permanent damage. Collaboration between psychiatrist, nephrologist and patients themselves is essential. In patients with Li-NDI and/or Li-NP cessation of lithium therapy and/or switch to another mood stabilizer should be considered. In patients with Li-NDI, off label therapy with amiloride can be useful.

Comparison of 71 bipolar disorder pharmacotherapies for kidney disorder risk: The potential hazards of polypharmacy

BACKGROUND

This study compared the largest set of bipolar disorder pharmacotherapies to date (71 drugs and drug combinations) for risk of kidney disorders (KDs).

METHODS

This retrospective observational study used the IBM MarketScan® database to analyze data on 591,052 adults with bipolar disorder without prior nephropathy, for onset of KDs (of "moderate" or "high" severity) following psychopharmacotherapy (lithium, mood stabilizing anticonvulsants [MSAs], antipsychotics, antidepressants), or "No drug". Cox regression models included fixed pre-treatment covariates and time-varying drug exposure covariates to estimate the hazard ratio (HR) of each treatment versus "No drug".

RESULTS

Newly observed KD occurred in 14,713 patients. No regimen had significantly lower risk of KDs than "No drug". The HR estimates ranged 0.86-2.66 for "all" KDs and 0.87-5.30 for "severe" KDs. As additional drugs were combined to compare more complex polypharmacies, higher HRs were consistently observed. Most regimens containing lithium, MSAs, or antipsychotics had a higher risk than "No drug" (p < 0.05). The risk for "all" and "severe" KDs was highest respectively on monoamine oxidase inhibitors (MAOIs) (HR = 2.66, p = 5.73 × 10^-5), and a lithium-containing four-class combination (HR = 5.30, p = 2.46 × 10^-9). The HR for lithium monotherapy was 1.82 (p = 4.73 × 10^-17) for "severe" KDs.

LIMITATIONS

The limitations inherent for an observational study were non-randomized assignment of patients to treatment groups, non-standardization of diagnostic decisions, and non-uniform quality of data collection. No correction was made for medication dosage.

CONCLUSIONS

The findings support literature concerns about lithium nephrotoxicity and highlight the potential risks of MAOIs, MSAs, antipsychotics and psychotropic polypharmacy.

Factors related to lithium blood concentrations in Chinese Han patients with bipolar disorder

Background: The goal of this study was to identify the physiological factors related to the blood concentration of lithium in Chinese Han patients with bipolar disorder (BD). Materials and methods: A total of 186 Chinese Han patients with BD were assessed. Patients were recruited from the Anhui Mental Health Center. The concentrations of serum lithium were measured by a Dimension RxL Max biochemistry analyzer. Physiological factors, including body weight, body mass index (BMI), and routine laboratory parameters, were collected. Relationships between the serum lithium concentration and relevant clinical data were analyzed by Pearson correlation tests, and the independent relationships were determined by multivariate linear regression analysis. Results: Pearson correlation analysis showed that serum lithium concentrations were positively correlated with creatinine concentrations (r=0.147, P=0.046), Mg²⁺ concentrations (r=0.151, P=0.04), and the percentage of neutrophils (r=0.178, P=0.015) and negatively correlated with high-density lipoprotein (HDL) concentrations (r=-0.142, P=0.05), apolipoprotein A1 concentrations (r=-0.169, P=0.02), and Na⁺ concentrations (r=-0.148, P=0.046) in 186 patients with BD. Furthermore, multivariate linear regression analysis showed that serum lithium concentrations were negatively associated with Na⁺ concentrations and positively associated with the percentage of neutrophils. Conclusion: These results suggest that physiological factors, including creatinine, HDL, apolipoprotein A1, Na⁺, and Mg²⁺ concentrations and percentage of neutrophils, might be related to serum lithium concentrations and provide a basis for parameter selection of lithium population pharmacokinetics in Chinese Han patients with BD.

Drug information update. Lithium and chronic kidney disease: debates and dilemmas

Lithium is an established treatment for bipolar disorder and an augmenting agent for treatment-resistant depression. Despite awareness of renal adverse effects, including chronic kidney disease, for the past five decades, there has been a lack of research evidence. This has led to debates around the existence and magnitude of the risk. This article discusses the current evidence base regarding the link between lithium and chronic kidney disease, monitoring of renal functions and its clinical implications.

Long-term lithium treatment in bipolar disorder: effects on glomerular filtration rate and other metabolic parameters

Background

Concerns about potential adverse effects of long-term exposure to lithium as a mood-stabilizing treatment notably include altered renal function. However, the incidence of severe renal dysfunction; rate of decline over time; effects of lithium dose, serum concentration, and duration of treatment; relative effects of lithium exposure vs. aging; and contributions of sex and other factors all remain unclear.

Methods

Accordingly, we acquired data from 12 collaborating international sites and 312 bipolar disorder patients (6142 person-years, 2669 assays) treated with lithium carbonate for 8–48 (mean 18) years and aged 20–89 (mean 56) years. We evaluated changes of estimated glomerular filtration rate (eGFR) as well as serum creatinine, urea–nitrogen, and glucose concentrations, white blood cell count, and body-mass index, and tested associations of eGFR with selected factors, using standard bivariate contrasts and regression modeling.

Results

Overall, 29.5% of subjects experienced at least one low value of eGFR (<60 mL/min/1.73 m²), most after ≥15 years of treatment and age > 55; risk of ≥2 low values was 18.1%; none experienced end-stage renal failure. eGFR declined by 0.71%/year of age and 0.92%/year of treatment, both by 19% more among women than men. Mean serum creatinine increased from 0.87 to 1.17 mg/dL, BUN from 23.7 to 33.1 mg/dL, glucose from 88 to 122 mg/dL, and BMI from 25.9 to 26.6 kg/m². By multivariate regression, risk factors for declining eGFR ranked: longer lithium treatment, lower lithium dose, higher serum lithium concentration, older age, and medical comorbidity. Later low eGFR was also predicted by lower initial eGFR, and starting lithium at age ≥ 40 years.

Limitations

Control data for age-matched subjects not exposed to lithium were lacking.

Conclusions

Long-term lithium treatment was associated with gradual decline of renal functioning (eGFR) by about 30% more than that was associated with aging alone. Risk of subnormal eGFR was from 18.1% (≥2 low values) to 29.5% (≥1 low value), requiring about 30 years of exposure. Additional risk factors for low eGFR were higher serum lithium level, longer lithium treatment, lower initial eGFR, and medical comorbidity, as well as older age.

Long-term effect of lithium maintenance therapy on estimated glomerular filtration rate in patients with affective disorders: a population-based cohort study

BACKGROUND

For more than 40 years, the long-term effect of lithium maintenance therapy on renal function has been debated. We aimed to assess the effect of lithium maintenance therapy on estimated glomerular filtration rate (eFGR) in patients with affective disorders, and explore predictors for a decrease in eGFR.

METHODS

This population-based cohort study included adult patients (18-65 years of age at baseline) in Tayside (Scotland, UK) who had recently started on lithium maintenance treatment between Jan 1, 2000, and Dec 31, 2011 (retrospectively assigned to the lithium group) or those with exposure to other first-line drugs used in the treatment of affective disorders (quetiapine, olanzapine, and semisodium valproate) during the same period (retrospectively assigned to the comparator group). Patients had to have at least 6 months of (incidence) exposure to lithium or any of the comparator drugs, at least two eGFR values available in the observation period (one at baseline and at least one after ≥6 months post baseline). We excluded patients with previous exposure to lithium or one of the comparator drugs, those with a previous diagnosis of schizophrenia or other psychotic disorder, those with glomerular disease, tubulo-interstitial disease, or chronic kidney disease stages 4-5 at baseline, and those who had undergone renal transplant before exposure. Maximum follow-up was 12 years. Data were provided by the University of Dundee Health Informatics Centre, who have access to health-related population-based datasets containing data for every patient registered with a regional family doctor. Each patient has a unique ten-digit identifier, the Community Health Index, enabling us to link laboratory tests, dispensed community prescriptions, Scottish Morbidity Records, and mortality records to the patient. All data were anonymised according to Health Informatics Centre standard operating procedures. The primary outcome was the change per year in the eGFR, adjusted for age, sex, and baseline eGFR, and analysed by random coefficient models.

FINDINGS

1120 patients (305 exposed to lithium and 815 to comparator drugs) qualified for inclusion, providing 13 963 eGFR values over 12 years. The mean duration of exposure to lithium was 55 months (SD 42; range 6-144). Mean annual decline in eGFR (adjusted for age, sex, and baseline eGFR) was 1·3 mL/min per 1·73 m(2) (SE 0·2) in the lithium group, which did not differ significantly to that in the comparator group (0·9 mL/min/1·73 m(2) [SE 0·15]). After adjustment for additional confounders, the monthly decline in eGFR attributable to lithium exposure amounted to 0·02 mL/min per 1·73 m(2) (SE 0·02, p=0·30). As a post-hoc secondary outcome, we estimated the annual decline in eGFR for the lithium group to be 1·0 mL/min per 1·73 m(2) (SE 0·2), which again did not differ significantly to that in the comparator group (0·4 mL/min/1·73 m(2) [SE 0·2]. Modelling identified significant predictors for eGFR decline as age, baseline eGFR, comorbidities, co-prescriptions of nephrotoxic drugs, and episodes of lithium toxicity; however, duration of exposure to lithium and mean serum lithium level were not significant predictors for eGFR decline.

INTERPRETATION

Our analysis suggests no effect of stable lithium maintenance therapy (lithium levels in therapeutic range) on the rate of change in eGFR over time. Our results therefore contradict the idea that long-term lithium therapy is associated with nephrotoxicity in the absence of episodes of acute intoxication and that duration of therapy and cumulative dose are the major determinants of toxicity.

FUNDING

None.

Lithium nephrotoxicity

Reports of toxic effects on the kidney of lithium treatment emerged very soon after lithium therapy was introduced. Lithium-induced nephrogenic diabetes insipidus is usually self-limiting or not clinically dangerous. Some reports of irreversible chronic kidney disease and renal failure were difficult to attribute to lithium treatment since chronic kidney disease and renal failure exist in the population at large. In recent years, large-scale epidemiological studies have convincingly shown that lithium treatment elevates the risk of chronic kidney disease and renal failure. Most patients do not experience renal side effects. The most common side effect of polyuria only weakly predicts increasing creatinine or reduced kidney function. Among those patients who do experience decrease in creatinine clearance, some may require continuation of lithium treatment even as their creatinine increases. Other patients may be able to switch to a different mood stabilizer medication, but kidney function may continue to deteriorate even after lithium cessation. Most, but not all, evidence today recommends using a lower lithium plasma level target for long-term maintenance and thereby reducing risks of severe nephrotoxicity.

Effects of antipsychotics, antidepressants and mood stabilizers on risk for physical diseases in people with schizophrenia, depression and bipolar disorder

People with severe mental illness have a considerably shorter lifespan than the general population. This excess mortality is mainly due to physical illness. Next to mental illness-related factors, unhealthy lifestyle, and disparities in health care access and utilization, psychotropic medications can contribute to the risk of physical morbidity and mortality. We systematically reviewed the effects of antipsychotics, antidepressants and mood stabilizers on physical health outcomes in people with schizophrenia, depression and bipolar disorder. Updating and expanding our prior systematic review published in this journal, we searched MEDLINE (November 2009 - November 2014), combining the MeSH terms of major physical disease categories (and/or relevant diseases within these categories) with schizophrenia, major depressive disorder and bipolar disorder, and the three major psychotropic classes which received regulatory approval for these disorders, i.e., antipsychotics, antidepressants and mood stabilizers. We gave precedence to results from (systematic) reviews and meta-analyses wherever possible. Antipsychotics, and to a more restricted degree antidepressants and mood stabilizers, are associated with an increased risk for several physical diseases, including obesity, dyslipidemia, diabetes mellitus, thyroid disorders, hyponatremia; cardiovascular, respiratory tract, gastrointestinal, haematological, musculoskeletal and renal diseases, as well as movement and seizure disorders. Higher dosages, polypharmacy, and treatment of vulnerable (e.g., old or young) individuals are associated with greater absolute (elderly) and relative (youth) risk for most of these physical diseases. To what degree medication-specific and patient-specific risk factors interact, and how adverse outcomes can be minimized, allowing patients to derive maximum benefits from these medications, requires adequate clinical attention and further research.

Effects of 10 to 30 years of lithium treatment on kidney function

Long-term lithium treatment is associated with end-stage renal disease, but there is little evidence of a clinically significant reduction in renal function in most patients. We previously found that 1.5% of people who took lithium from the 1960s and 1970s developed end-stage renal disease; however, none of the patients who started after 1980 had end-stage renal disease. Here we aimed to study the prevalence and extent of kidney damage during the course of long-term lithium treatment since 1980. We retrieved serum lithium and creatinine levels from 4879 patients examined between 1 January 1981 and 31 December 2010. Only patients who started their lithium treatment during the study period and had at least 10 years of cumulative treatment were included. The study group comprised 630 adult patients (402 women and 228 men) with normal creatinine levels at the start of lithium treatment. There was a yearly increase in median serum creatinine levels already from the first year of treatment. About one-third of the patients who had taken lithium for 10-29 years had evidence of chronic renal failure but only 5% were in the severe or very severe category. The results indicate that a substantial proportion of adult patients who are treated with lithium for more than a decade develop signs of renal functional impairment, also when treated according to modern therapeutic principles. Our results emphasise that lithium treatment requires continuous monitoring of kidney function.

Short-term effects of lithium on white blood cell counts and on levels of serum thyroid-stimulating hormone and creatinine in adolescent inpatients: a retrospective naturalistic study

OBJECTIVE

The purpose of this study was to determine if the known side effects of lithium in adults may be generalized to younger patients with psychiatric disorders.

METHODS

A retrospective naturalistic study design was used. Data were collected from the database of a tertiary pediatric medical center covering the years 1994-2010. Included were patients hospitalized for bipolar and non-bipolar disorders and treated with lithium, alone or in combination with other medications. The electronic medical files were reviewed for changes in thyroid and kidney function and for hematological parameters during the course of treatment.

RESULTS

Sixty-one patients 12.5-20.4 years of age (mean 16.94±1.66) met the study criteria: 33 with bipolar disorder and 28 with a non-bipolar disorder. Mean duration of lithium treatment (mean lithium blood level, 0.73±0.24 mEq/L) was 193.68±254.35 days. Mean levels of thyroid-stimulating hormones (TSH) rose significantly from baseline to last measurement (3.16±2.68 vs. 1.52±0.92 mU/L; paired t=-5.19, df=50, p<0.001); in 25% of patients, TSH levels at the last measurement were above normal (≥4 mU/L). Only one patient developed TSH values >10 mU/L (the threshold considered clinically significant). Positive correlation was found between pre- and posttreatment TSH levels (Pearson's r=0.60; n=51, p<0.05). White blood cell count (WBC) also increased significantly following lithium treatment (7195±2151 vs. 7944±2096 cells/mm(3); t=2.83, df=60, p=0.006). No significant changes were noted in serum creatinine levels. There was no difference in these parameters between patients treated with lithium alone or in combination with other medications.

CONCLUSIONS

Lithium treatment in adolescents with bipolar or non-bipolar disorders is associated with a significant increase in blood TSH levels and WBC count. Lithium-treated adolescent inpatients with a high basal TSH level may be at risk of developing pituitary-thyroid axis dysregulation. Therefore, baseline measurement of thyroid functions and serial monitoring throughout treatment are recommended.

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.

Renal failure in lithium-treated bipolar disorder: a retrospective cohort study

Objective

Lithium users are offered routine renal monitoring but few studies have quantified the risk to renal health. The aim of this study was to assess the association between use of lithium carbonate and incidence of renal failure in patients with bipolar disorder.

Methods

This was a retrospective cohort study using the General Practice Research Database (GPRD) and a nested validation study of lithium exposure and renal failure. A cohort of 6360 participants aged over 18 years had a first recorded diagnosis of bipolar disorder between January 1, 1990 and December 31, 2007. Data were examined from electronic primary care records from 418 general practices across the UK. The primary outcome was the hazard ratio for renal failure in participants exposed to lithium carbonate as compared with non-users of lithium, adjusting for age, gender, co-morbidities, and poly-pharmacy.

Results

Ever use of lithium was associated with a hazard ratio for renal failure of 2.5 (95% confidence interval 1.6 to 4.0) adjusted for known renal risk factors. Absolute risk was age dependent, with patients of 50 years or older at particular risk of renal failure: Number Needed to Harm (NNH) was 44 (21 to 150).

Conclusions

Lithium is associated with an increased risk of renal failure, particularly among the older age group. The absolute risk of renal failure associated with lithium use remains small.

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.

Lithium usage and renal function testing in a large UK community population; a case-control study

OBJECTIVE

This study investigates the prevalence of lithium use, monitoring practice and associated effects on renal function in a large UK community sample.

METHOD

A large population-based renal function database was cross-referenced with a general practitioner database of 404,673 patients. The renal function of patients prescribed lithium during the 2-year period was compared with that of matched controls. The renal monitoring patterns of these cases were investigated in a naturalistic observational study. Data underwent parametric testing - continuous variables by analysis of variance, with appropriate adjustment, and categorical outcomes by χ(2) testing. Block analysis of variance was undertaken on case-control data.

RESULTS

A total of 422 patients in the database were prescribed lithium. Renal function monitoring in accordance with published guidelines occurred in 69% of patients. Patients taking lithium had a significantly higher serum creatinine (5.8 μmol/L, P<.001) and lower glomerular filtration rate (5.9 ml/min, P<.001) when compared to matched controls.

CONCLUSIONS

This is the first study carried out in a large community sample. Lithium remains widely prescribed in the community setting. The study confirms that lithium has a statistically and clinically significant negative effect on renal function. Despite published guidelines and recognition of the importance of serial measurements, monitoring of renal function is inconsistent.

Novel markers of kidney injury in bipolar patients on long-term lithium treatment

OBJECTIVES

We assessed kidney function in long-term lithium-treated bipolar patients compared with age-matched patients not taking lithium, including novel markers of kidney injury such as plasma neutrophil gelatinase-associated lipocalin (NGAL) and urinary beta-2 microglobulin (β2-MG) METHODS: The study comprised 120 patients with bipolar disorder of which 90 (30 males and 60 females) have been receiving lithium for 5-38 (mean 16) years, and 30 (10 males and 20 females) have never been exposed to lithium.

RESULTS

Lithium-treated patients, both men and women, showed significantly higher plasma NGAL and urinary β2-MG and lower urine specific gravity and estimated glomerular filtration rate (eGFR), compared with patients not taking lithium. In these patients, serum NGAL did not correlate with any clinical feature or other parameter of kidney function. Urinary β2-MG correlated with serum creatinine and eGFR in the whole group of lithium-treated patients and in addition, in males, with duration of illness, duration of lithium treatment, and urine specific gravity.

CONCLUSIONS

Lithium treatment causes an impairment of kidney function reflected also by abnormal levels of novel markers of kidney injury. Of these, urinary β2-MG, as a marker of tubular function seems to be better predictor than serum NGAL in lithium-treated patients because it shows multiple clinical and biochemical correlations, especially in men.

Chronic renal failure in lithium-using geriatric patients: effects of lithium continuation versus discontinuation--a 60-month retrospective study

OBJECTIVE

Lithium remains an important treatment in bipolar disorder. Although lithium is often discontinued because of signs of renal failure, it is unclear if this alters the course of renal function in the majority of patients. We hypothesize that in geriatric patients with chronic renal failure (CRF), who have a high burden of medical illness, lithium continuation does not significantly impact renal function (glomerular filtration rate (eGFR)).

METHODS

We conducted a retrospective study of tertiary-care geriatric psychiatry outpatients with a history of lithium use and evidence of CRF (eGFR ≤ 60 ml/min/1.73 m2 on ≥ 2 occasions in ≥ 3 months). The 27 patients who met these criteria were divided into lithium 'continuers' (continued use ≥ 2 years following CRF) and 'discontinuers'. Mean eGFR and creatinine were followed at 21 and 60 months after developing CRF.

RESULTS

Mean serum eGFR and creatinine were not significantly different between groups at any time during follow-up. When comparing renal function at 60 months to baseline, a trend towards increased creatinine was seen in continuers (p = 0.06) but not in discontinuers. Changes in eGFR in continuers and discontinuers after 60 months did not achieve statistical significance (p = 0.35 and 0.98). However, clinically important decreases in eGFR occurred in the majority of continuers but in none of the discontinuers.

CONCLUSIONS

There was a trend towards declining renal function in lithium continuers at 60-month follow-up. Future prospective longitudinal studies will be needed to confirm our findings. We suggest vigilance and close monitoring of renal function when continuing CRF patients on lithium for extended periods.

Lithium toxicity profile: a systematic review and meta-analysis

BACKGROUND

Lithium is a widely used and effective treatment for mood disorders. There has been concern about its safety but no adequate synthesis of the evidence for adverse effects. We aimed to undertake a clinically informative, systematic toxicity profile of lithium.

METHODS

We undertook a systematic review and meta-analysis of randomised controlled trials and observational studies. We searched electronic databases, specialist journals, reference lists, textbooks, and conference abstracts. We used a hierarchy of evidence which considered randomised controlled trials, cohort studies, case-control studies, and case reports that included patients with mood disorders given lithium. Outcome measures were renal, thyroid, and parathyroid function; weight change; skin disorders; hair disorders; and teratogenicity.

FINDINGS

We screened 5988 abstracts for eligibility and included 385 studies in the analysis. On average, glomerular filtration rate was reduced by -6·22 mL/min (95% CI -14·65 to 2·20, p=0·148) and urinary concentrating ability by 15% of normal maximum (weighted mean difference -158·43 mOsm/kg, 95% CI -229·78 to -87·07, p<0·0001). Lithium might increase risk of renal failure, but the absolute risk was small (18 of 3369 [0·5%] patients received renal replacement therapy). The prevalence of clinical hypothyroidism was increased in patients taking lithium compared with those given placebo (odds ratio [OR] 5·78, 95% CI 2·00-16·67; p=0·001), and thyroid stimulating hormone was increased on average by 4·00 iU/mL (95% CI 3·90-4·10, p<0·0001). Lithium treatment was associated with increased blood calcium (+0·09 mmol/L, 95% CI 0·02-0·17, p=0·009), and parathyroid hormone (+7·32 pg/mL, 3·42-11·23, p<0·0001). Patients receiving lithium gained more weight than did those receiving placebo (OR 1·89, 1·27-2·82, p=0·002), but not those receiving olanzapine (0·32, 0·21-0·49, p<0·0001). We recorded no significant increased risk of congenital malformations, alopecia, or skin disorders.

INTERPRETATION

Lithium is associated with increased risk of reduced urinary concentrating ability, hypothyroidism, hyperparathyroidism, and weight gain. There is little evidence for a clinically significant reduction in renal function in most patients, and the risk of end-stage renal failure is low. The risk of congenital malformations is uncertain; the balance of risks should be considered before lithium is withdrawn during pregnancy. Because of the consistent finding of a high prevalence of hyperparathyroidism, calcium concentrations should be checked before and during treatment.

FUNDING

National Institute for Health Research Programme Grant for Applied Research.