Olanzapine-induced glucose dysregulation

A case report and literature review of olanzapine-associated hyperglycemia with previous history of gestational diabetes

Background

Olanzapine (Zyprexa) package labeling includes a warning for hyperglycemia, stating physicians should consider the risks and benefits when prescribing olanzapine to patients with an established diagnosis of diabetes mellitus or having borderline increased blood glucose levels. A case report of olanzapine-associated hyperglycemia in a patient with a history of gestational diabetes mellitus (GDM) is presented and literature review is discussed.

Case Report

A 33-year-old female with a past medical history of bipolar disorder, cocaine and amphetamine use disorder, hypertension, and GDM was initiated on olanzapine 5 mg PO daily which was subsequently titrated to 25 mg daily. On day 15 of admission, she developed signs and symptoms of hyperglycemia, with blood glucose readings >500 mg/dL. Insulin was initiated, olanzapine was discontinued, and her blood glucose began improving. She was later discharged on ziprasidone 20 mg PO twice daily.

Discussion

There have been several case reports published on olanzapine-induced hyperglycemia. This is the first case report to specifically recognize a history of GDM as a potential risk factor for developing olanzapine-associated hyperglycemia.

Conclusion

Adverse effect profiles and patient-specific risk factors should be considered when selecting appropriate antipsychotic treatment. Olanzapine may not be an ideal medication choice for a person with a history of GDM; however, if olanzapine is indicated, then close blood glucose monitoring is recommended.

Metabolic Effects of Aripiprazole and Olanzapine Multiple-Dose Treatment in a Randomised Crossover Clinical Trial in Healthy Volunteers: Association with Pharmacogenetics

Introduction

Aripiprazole and olanzapine are atypical antipsychotics. Both drugs can induce metabolic changes; however, the metabolic side effects produced by aripiprazole are more benign. The aim of the study was to evaluate if aripiprazole and olanzapine alter prolactin levels, lipid and glucose metabolism and hepatic, haematological, thyroid and renal function.

Methods

Twenty-four healthy volunteers received a daily oral dose of 10 mg aripiprazole and 5 mg olanzapine tablets for 5 days in a crossover randomised clinical trial and were genotyped for 51 polymorphisms in 18 genes by qPCR. Drug plasma concentrations were measured by LC–MS. The biochemical and haematological analyses were performed by enzymatic methods.

Results

Olanzapine induced hyperprolactinaemia but aripiprazole did not. Dopamine D3 receptor (DRD3) Ser/Gly and ATP binding cassette subfamily B member 1 (ABCB1) rs10280101, rs12720067 and rs11983225 polymorphisms and cytochrome P450 3A (CYP3A) phenotype had an impact on plasma prolactin levels. C-peptide concentrations were higher after aripiprazole administration and were influenced by catechol-O-methyltransferase (COMT) rs4680 and rs13306278 polymorphisms. Olanzapine and the UDP glucuronosyltransferase family 1 member A1 (UGT1A1) rs887829 polymorphism were associated with elevated glucose levels. CYP3A poor metabolizers had increased insulin levels. Volunteers’ weight decreased significantly during aripiprazole treatment and a tendency for weight gain was observed during olanzapine treatment. Triglyceride concentrations decreased as a result of olanzapine and aripiprazole treatment, and varied on the basis of CYP3A phenotypes and the apolipoprotein C-III (APOC3) rs4520 genotype. Cholesterol levels were also decreased and depended on 5-hydroxytryptamine receptor 2A (HTR2A) rs6314 polymorphism. All hepatic enzymes, platelet and albumin levels, and prothrombin time were altered during both treatments. Additionally, olanzapine reduced the leucocyte count, aripiprazole increased free T4 and both decreased uric acid concentrations.

Conclusions

Short-term treatment with aripiprazole and olanzapine had a significant influence on the metabolic parameters. However, it seems that aripiprazole provokes less severe metabolic changes.

Trial Registration

Clinical trial registration number (EUDRA-CT): 2018-000744-26

Graphical Abstract

Electronic Supplementary Material

The online version of this article (10.1007/s12325-020-01566-w) contains supplementary material, which is available to authorized users.

Olanzapine-induced Cataract in a Teenage Girl

Cataract, defined as cloudiness of the lens, is a common adverse effect of first-generation antipsychotic medications. Newer generation antipsychotics, also known as atypical antipsychotics, are less commonly associated with cataract. A 19-year-old girl with underlying schizophrenia on olanzapine for the past two years complained of gradual blurring of vision in both eyes for four months prior to presentation. On examination, the best corrected visual acuity was counting finger in both eyes. The anterior segment examination showed bilateral diffuse cortical cataract precluding fundus examination. Systemic examination was unremarkable. Blood investigations revealed a high random blood sugar, which normalised after she was initiated on oral hypoglycemic medication. After bilateral lens aspiration, her visual acuity was 6/6 bilaterally. Olanzapine may be cataractogenic via its action as a serotonin antagonist, which results in reduced glucose responsiveness of the pancreatic beta-cells. Patients on anti-psychotic medication are at risk of developing diabetes mellitus and cataract compared to the general population. Screening for diabetes mellitus should be part of the follow-up of these patients. Ophthalmological evaluation is warranted in the presence of visual complaints.

The metabolic side effects of 12 antipsychotic drugs used for the treatment of schizophrenia on glucose: a network meta-analysis

BACKGROUND

Antipsychotics have serious metabolic side effects on blood glucose. However, the comparative influence of these drugs on blood glucose levels has not been comprehensively evaluated. We conducted a network meta-analysis to create a hierarchy of the side effects of 12 antipsychotic drugs on changes in blood glucose levels.

METHODS

A systematic search of the PubMed, EMBASE and Cochrane databases (last search June 2016) was conducted to identify studies that reported randomized controlled trials (RCTs) comparing changes in blood glucose levels between patients receiving one of 12 antipsychotic drugs or a placebo for the treatment of schizophrenia or related disorders. The studies we searched were limited to those published in English. Two reviewers independently extracted data. The primary outcome of interest was changes in fasting glucose levels.

RESULTS

We included 47 studies with 114 relevant arms. Of the antipsychotic drugs, only olanzapine was associated with significantly increased glucose levels compared to a placebo (mean difference (MD) = 3.95, 95% confidence interval (CI) = 0.14 to 7.76). Moreover, olanzapine was associated with a significantly greater change in the glucose levels than ziprasidone (MD = 5.51, 95% CI = 1.62 to 9.39), lurasidone (MD = 5.58, 95% CI = 0.53 to 10.64) or risperidone (MD = 3.05, 95% CI = 0.87 to 5.22). Ziprasidone and lurasidone were associated with minimal glucose changes compared to the other antipsychotics.

CONCLUSIONS

Olanzapine was associated with a significantly greater change in blood glucose levels than ziprasidone, lurasidone, risperidone or placebo treatment. The application of a hierarchy of glucose metabolism-related side effects may help clinicians tailor the choice of antipsychotic drug to meet the needs of individual patients.

Atypical Antipsychotics and Diabetes: Discussion and Monitoring Recommendations

Objective:

To discuss the relationship between atypical antipsychotics (AAPs) and diabetes and to report new monitoring recommendations for patients being prescribed AAPs.

Data Sources:

Articles were identified through searches of MEDLINE and PubMed (1966–March 2004). Search terms included hyperglycemia, diabetes, glucose, atypical antipsychotics, clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole. Only articles published in the English language were included in the search. Additionally, bibliographies of articles cited were used to identify additional articles.

Study Selection and Data Extraction:

All available articles identified by the data sources were reviewed and those deemed relevant to the review were included.

Data Synthesis:

Information pertaining to diabetes/hyperglycemia risk in case reports and submissions to the Medwatch system prompted the FDA to require labeling changes for all AAPs. The exact relationship between AAPs and diabetes remains unclear. The association is clouded by the fact that patients with schizophrenia are, in general, at higher risk for diabetes mellitus. Sedentary lifestyle and poor dietary intake are 2 possible contributing causes of diabetes in patients with schizophrenia. Weight gain or other metabolic effects of AAPs may put patients at further risk of developing diabetes. The American Diabetes Association, American Psychiatric Association, American Association of Clinical Epidemiologists, and North American Association for the Study of Obesity have released a joint consensus statement addressing some of the concerns related to AAP use.

Conclusions:

Because of the apparent increased risk of diabetes in patients taking AAPs, monitoring weight, fasting blood glucose, blood pressure, and lipids should be a part of the baseline assessment and ongoing care.

Glucose Disturbances and Atypical Antipsychotic Use in the Intensive Care Unit

PURPOSE

Chronic use of atypical antipsychotics may lead to metabolic abnormalities including hyperglycemia. Although evidence supports acute hyperglycemic episodes associated with atypical antipsychotic use, the acute use of atypical antipsychotics in the intensive care unit (ICU) setting has not been studied. The purpose of this study is to evaluate the occurrence of hyperglycemia in ICU patients receiving newly prescribed atypical antipsychotic.

SUMMARY

Of the 273 patient charts reviewed, 50 patients were included in this study. Approximately 45% of patients experienced at least 1 hyperglycemic episode (blood glucose >180 mg/dL) after the initiation of an atypical antipsychotic in the ICU. Of the patients experiencing at least 1 hyperglycemic episode, 60% experienced multiple distinct hyperglycemic episodes. In this study, quetiapine was the most commonly used atypical antipsychotic, 19 (38%) patients were discharged from the ICU on the atypical antipsychotic, 6 (12%) patients died in the ICU, and 31 (62%) patients were treated with an antihyperglycemic agent. Logistic regression analysis showed that women and ICU patients with a higher Acute Physiology and Chronic Health Evaluation II (APACHE II) score were significantly more likely to have multiple hyperglycemic episodes.

CONCLUSION

Patients admitted to the ICU and initiated on an atypical antipsychotic may develop hyperglycemia independent of other glucose-elevating factors. The direct correlation of these agents to resulting acute hyperglycemia is unknown. Further studies are needed to investigate the link between atypical antipsychotics and acute hyperglycemia and the clinical significance of the impact on patient outcomes.

Fatal diabetic ketoacidosis and antipsychotic medication

Hyperglycemia and new onset diabetes have been described with certain antipsychotic medications and some of the initial presentations are fatal diabetic ketoacidosis (DKA). We report 17 deaths due to DKA in psychiatric patients treated with second generation antipsychotic medications. Death certificates and toxicology data were searched for DKA and hyperglycemia. We reviewed the medical examiner records which included the autopsy, toxicology, police, and medical examiner investigators' reports. The decedents ranged in age from 32 to 57 years (average 48 years). There were 15 men and two women. The immediate cause of death was DKA in all. The psychiatric disorders included: 10 schizophrenia, three bipolar/schizophrenia, two bipolar, and two major depression. The most frequent atypical antipsychotic medications found were quetiapine and olanzapine followed by risperidone. In 16 deaths, we considered the medication as primary or contributory to the cause of death.

[Utilisation of atypical antipsychotic drugs in institutionalised elderly persons and prevalence of metabolic alterations]

OBJECTIVES

Describe and evaluate atypical antipsychotics utilisation on the institutionalized elderly population of the Valencian Community and prevalence of associated metabolic alterations.

MATERIAL AND METHODS

Multicentre transversal descriptive study on medication utilisation and prevalence case-control of alterations of glycaemia, cholesterol and triglycerides. The statistical analysis of metabolic alterations is performed from the difference in prevalence and its statistical signification between the control group and the study group.

RESULTS

681 patients were included (study group, 344; control group, 337) from 20 social-health-care centres. 18.5% of the institutionalised patients are being treated with atypical antipsychotics. The most frequent diagnoses are: behavioural alterations associated with dementia (63.6%) and schizophrenia (18.4%). Risperidone is the most frequently used antipsychotic (66.0%). For all the drugs in general the doses used adjust to those recommended for elderly patients. The prevalence of alterations in glycaemia, cholesterol and triglycerides metabolism in the group under study is 23.96%, 34.83%, and 26.29%, respectively, with no statistically significant differences against the control group. The analysis by type of drug did not show significant differences.

CONCLUSIONS

The results obtained show that utilisation of atypical antipsychotics in elderly patients complies with the established general recommendations. The doses used in elderly patients with behavioural alterations associated with dementia, mostly treated with risperidone, do not have a significant impact over prevalence increase of metabolic alterations.

Atypical antipsychotics and diabetes mellitus

Recently, increasing attention has been drawn to the potential diabetogenic effect of novel antipsychotics. Until now, large prospective studies examining the relationship between atypical antipsychotics and impaired glucose metabolism have been lacking. However, the case reports and retrospective studies that we review here suggest an increased risk of developing diabetes mellitus (DM) in patients treated with atypical antipsychotics compared to schizophrenic patients treated with conventional antipsychotics or those without treatment. Although most atypical antipsychotic agents might have a diabetogenic potential, the risk of developing DM might be higher in patients treated with either clozapine or olanzapine than with risperidone, whereas data on quetiapine and ziprasidone is presently limited and needs further attention. Possible mechanisms include the induction of peripheral insulin resistance and the direct influence on pancreatic beta-cell function by 5-HT1A/2A/2C receptor antagonism, by inhibitory effects via alpha 2-adrenergic receptors or by toxic effects. On the other hand, atypical antipsychotics might not be an independent risk factor for the development of DM, but hasten the onset of DM in patients bearing other risk factors. It is suggested that schizophrenic patients should be monitored for the occurrence of glucose metabolism abnormalities before starting atypical antipsychotics, and at a 3-month interval at least during therapy.

Olanzapine in long-term treatment for bipolar disorder

BACKGROUND

Many patients with bipolar disorder require long-term treatment to prevent recurrence. Antipsychotic drugs are often used to treat acute manic episodes. It is important to clarify whether olanzapine could have a role in long-term prevention of manic and depressive relapses.

OBJECTIVES

To assess the effects of olanzapine, as monotherapy or adjunctive treatment, in preventing manic, depressive and mixed episodes in patients with bipolar affective disorder.

SEARCH STRATEGY

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (September 2006), the Cochrane Central Register of Controlled Trials (September 2006), MEDLINE (1966-December 2007), EMBASE (1980-2006), CINAHL (1982-2006), PsycINFO (1872-2006) and reference lists. We also contacted experts, trialists and pharmaceutical companies in the field.

SELECTION CRITERIA

Randomised controlled trials comparing olanzapine with placebo or other active treatment in long-term treatment of bipolar disorder.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information.

MAIN RESULTS

Five trials (1165 participants) were included in the review. There was no statistically significant difference between olanzapine and placebo (either alone or in combination with lithium or valproate) in terms of number of participants who experienced relapse into mood episode (random effects RR 0.68, 95% CI 0.43 to 1.07, p = 0.09; 2 studies, n=460), however restricting the analysis to the trial that compared olanzapine monotherapy versus placebo, there was a statistically significant difference in favour of olanzapine (RR 0.58, 95% CI 0.49 to 0.69, p<0.00001). No statistically significant difference was found between olanzapine and other mood stabilisers (lithium or valproate) in preventing symptomatic relapse for any mood episode, however, olanzapine was more effective than lithium in preventing symptomatic manic relapse (RR 0.59, 95% CI 0.39 to 0.89, p = 0.01; 1 study, n=361). Olanzapine either alone or as adjunctive treatment to mood stabilisers was associated with significantly greater weight gain than placebo. By contrast, olanzapine was associated with a lower rate of manic worsening, but with a higher rate of weight increase and depression than lithium.

AUTHORS' CONCLUSIONS

Though based on a limited amount of information, there is evidence that olanzapine may prevent further mood episodes in patients who have responded to olanzapine during an index manic or mixed episode and who have not previously had a satisfactory response to lithium or valproate. However, notwithstanding these positive results, the current evidence is stronger for lithium as first line maintenance treatment of bipolar disorder.

Atypical antipsychotic-induced metabolic side effects: insights from receptor-binding profiles

Atypical antipsychotic drugs offer several notable benefits over typical antipsychotics, including greater improvement in negative symptoms, cognitive function, prevention of deterioration, and quality of life, and fewer extrapyramidal symptoms (EPS). However, concerns about EPS have been replaced by concerns about other side effects, such as weight gain, glucose dysregulation and dyslipidemia. These side effects are associated with potential long-term cardiovascular health risks, decreased medication adherence, and may eventually lead to clinical deterioration. Despite a greater understanding of the biochemical effects of these drugs in recent years, the pharmacological mechanisms underlying their various therapeutic properties and related side effects remain unclear. Besides dopamine D(2) receptor antagonism, a characteristic feature of all atypical antipsychotic drugs, these agents also bind to a range of non-dopaminergic targets, including serotonin, glutamate, histamine, alpha-adrenergic and muscarinic receptors. This review examines the potential contribution of different receptors to metabolic side effects associated with atypical antipsychotic treatment for all seven agents currently marketed in the United States (risperidone, olanzapine, quetiapine, ziprasidone, aripiprazole, paliperidone and clozapine) and another agent (bifeprunox) in clinical development at the time of this publication.

Increased lactate levels and reduced pH in postmortem brains of schizophrenics: medication confounds

A number of postmortem studies have found decreased pH in brains of patients with schizophrenia. Insofar as lower pH has been associated with decreased mRNA expression in postmortem human brain, decreased pH in schizophrenia may represent an important potential confound in comparisons between patients and controls. We hypothesized that decreased pH may be related to increased concentration of lactic acid. However, in contrast to the previous notion that an increase in lactic acid represents evidence for primary metabolic abnormalities in schizophrenia, we hypothesized that this increase is secondary to prior antipsychotic treatment. We have tested this by first demonstrating that lactate levels in the cerebellum of patients with schizophrenia (n=35) are increased relative to control subjects (n=42) by 28%, p=0.001. Second, we have shown that there is an excellent correlation between lactate levels in the cerebellum and pH, and that this correlation is particularly strong in patients (r=-0.78, p=3E-6). Third, we have shown in rats that chronic haloperidol (0.8mg/kg/day) and clozapine (5mg/kg/day) increase lactic acid concentration in the frontal cortex relative to vehicle (by 31% and 22% respectively, p<0.01). These data suggest that lactate increases in postmortem human brain of patients with schizophrenia are associated with decreased pH and that these changes are possibly related to antipsychotic treatment rather than a primary metabolic abnormality in the prefrontal cortex of patients with schizophrenia.

Drug-Induced Endocrine and Metabolic Disorders

Complex interactions exist amongst the various components of the neuroendocrine system in order to maintain homeostasis, energy balance and reproductive function. These components include the hypothalamus-pituitary- adrenal and -gonadal axes, the renin-angiotensin-aldosterone system, the sympathetic nervous system and the pancreatic islets. These hormones, peptides and neurotransmitters act in concert to regulate the functions of many organs, notably the liver, muscles, kidneys, thyroid, bone, adrenal glands, adipocytes, vasculature, intestinal tract and gonads, through many intermediary pathways. Endocrine and metabolic disorders can arise from imbalance amongst numerous hormonal factors. These disturbances may be due to endogenous processes, such as increased secretion of hormones from a tumour, as well as exogenous drug administration. Drugs can cause endocrine abnormalities via different mechanisms, including direct alteration of hormone production, changes in the regulation of the hormonal axis, effects on hormonal transport, binding, and signalling, as well as similar changes to counter-regulatory hormone systems. Furthermore, drugs can affect the evaluation of endocrine parameters by causing interference with diagnostic tests. Common drug-induced endocrine and metabolic disorders include disorders of carbohydrate metabolism, electrolyte and calcium abnormalities, as well as drug-induced thyroid and gonadal disorders. An understanding of the proposed mechanisms of these drug effects and their evaluation and differential diagnosis may allow for more critical interpretation of the clinical observations associated with such disorders, better prediction of drug-induced adverse effects and better choices of and rationales for treatment.

Diabetes risk associated with use of olanzapine, quetiapine, and risperidone in veterans health administration patients with schizophrenia

To evaluate risk of new-onset type 2 diabetes associated with use of selected antipsychotic agents, the authors conducted a new-user cohort study in a national sample of US Veterans Health Administration patients with schizophrenia (and no preexisting diabetes). The authors studied 15,767 patients who initiated use of olanzapine, risperidone, quetiapine, or haloperidol in 1999-2001 after at least 3 months with no antipsychotic prescriptions. Patients were followed for just over 1 year. New-onset diabetes was identified through diagnostic codes and prescriptions for diabetes medication. In Cox proportional hazards regression adjusting for potential confounders, with patients initiating haloperidol use designated the reference group, diabetes risk was increased equally with new use of olanzapine (hazard ratio (HR) = 1.64, 95% confidence interval (CI): 1.22, 2.19), risperidone (HR = 1.60, 95% CI: 1.19, 2.14), or quetiapine (HR = 1.67, 95% CI: 1.01, 2.76). Diabetes risks were higher in patients under age 50 years. When data were reanalyzed with prevalent-user cohorts and matched case-control designs, results were similar, with slightly less elevated risk estimates. Assuming that the observed associations are causal, approximately one third of new cases of diabetes may be attributed to use of olanzapine, risperidone, and quetiapine in patients taking these medications. Prescribers should be mindful of diabetes risks when treating patients with schizophrenia.

Atypical antipsychotic drugs and diabetes mellitus in a large outpatient population: a retrospective cohort study

PURPOSE

Previous research has suggested an association between use of atypical antipsychotics and onset of diabetes mellitus. We sought to compare the incidence of new onset diabetes among patients receiving atypical antipsychotics, traditional antipsychotics or antidepressants.

METHODS

Retrospective cohort study of outpatients with claims for atypical antipsychotics (n = 10 265) compared to controls with claims for traditional antipsychotics (n = 4607), antidepressants (n = 60 856) or antibiotics (n = 59 878) in the administrative claims database of a large pharmaceutical benefit manager between June 2000 and May 2002. Main outcome measures were adjusted and unadjusted incidence rates of diabetes (new cases per 1000 per year) in a 12-month period, as measured using new prescriptions for antidiabetic drugs after a 6-month lead-in period.

RESULTS

Annual unadjusted incidence rates of diabetes (new cases per 1000 per year) were 7.5 for atypical antipsychotics, 11.3 for traditional antipsychotics, 7.8 for antidepressants and 5.1 for antibiotics. In multivariable analyses, age, male sex and Chronic Disease Score were associated with greater odds of diabetes onset. There were no statistically significant differences in outcome between the atypical antipsychotic, traditional antipsychotic and antidepressant groups. Multivariable comparisons among specific agents showed increased odds of diabetes for clozapine, olanzapine, ziprasidone and thioridazine (relative to risperidone), but these comparisons did not reach statistical significance.

CONCLUSIONS

In a large prescription claims database, outpatients taking atypical antipsychotics did not have higher rates of diabetes onset, compared to subjects taking traditional antipsychotics or antidepressants.

Prevalence of diabetes mellitus in chronic schizophrenic inpatients in relation to long-term antipsychotic treatment

BACKGROUND

Many reports indicate that the incidence and prevalence of diabetes mellitus is increased in schizophrenic patients and related to antipsychotic treatment. In an exploratory cross-sectional study we assessed the prevalence of type 2 diabetes mellitus in 266 chronic schizophrenic and schizoaffective inpatients and investigated whether the duration of antipsychotic treatment was related to the development of diabetes mellitus.

METHOD

We measured the non-fasting plasma glucose level in 266 inpatients with DSM IV diagnosis of schizophrenia or schizoaffective disorder in 5 different long-stay wards in the Netherlands. Measured variables were: age, sex, ethnicity, BMI, current antipsychotic treatment, duration of illness and duration of antipsychotic treatment.

RESULTS

The overall prevalence of type 2 diabetes mellitus was 9%, which is significantly higher than the prevalence of 4.9% in the general population (OR 1.89, CI 1.14-3.13; p<0.014). The prevalence was increased in two age cohorts: 30-39 years (3.8% vs. 0.3%, OR=13.29, CI=2.17-81.36, p=<0.005) and 40-49 years (9.3% vs. 1.5%, OR=6.74, CI=2.77-16.38, p=0.000). No new cases of diabetes mellitus were detected during the course of the study. The increased prevalence was found to be related to overweight and obesity. The time of exposure to antipsychotic treatment was not significantly correlated with the prevalence of diabetes mellitus when adjusted for age (F=0.804, df=1, p=0.371, respectively, F=0.194, df=1, p=0.660). Both typical and atypical antipsychotics contributed equally to the prevalence of diabetes mellitus.

CONCLUSION

No significant relation between long-term antipsychotic treatment and prevalence of diabetes mellitus was found. The high prevalence of diabetes mellitus in schizophrenic patients warrants screening of these patients already at young age for glucose disturbance.

Receptor occupancy-based analysis of the contributions of various receptors to antipsychotics-induced weight gain and diabetes mellitus

OBJECTIVE

Among various adverse reactions of atypical antipsychotics, weight gain and impaired glucose tolerance are clinically significant. The aim of this study is to analyze quantitatively the contributions of various receptors to these antipsychotics-induced adverse reactions based on the receptor occupancy theory.

METHODS

Two indices of antipsychotics-induced weight gain (the values estimated by a meta-analysis and the observed values in clinical trials) and the morbidity rate of type 2 diabetes mellitus during treatment with antipsychotics were taken from the literature. We calculated the estimated mean receptor occupancies of alpha1 adrenergic, alpha2 adrenergic, dopamine D2, histamine H1, muscarinic acetylcholine (mACh), serotonin 5-HT1A, 5-HT2A and 5-HT2C receptors by antipsychotics by using the pharmacokinetic parameters and receptor dissociation constants, and analyzed the correlation between the occupancies and the extent of adverse reactions as assessed using the aforementioned indices.

RESULTS

There were statistically significant correlations between the estimated occupancies of H1 and mACh receptors and antipsychotics-induced weight gain estimated by meta-analysis (r(s) = 0.81 and r(s) = 0.83, respectively, p < 0.01). There were also statistically significant correlations between these receptor occupancies and observed weight gain in clinical trials (r(s) = 0.66 in each case, p < 0.01). The morbidity rate of type 2 diabetes mellitus was highly correlated with H1, mACh, and 5-HT2C receptor occupancies (r(s) = 0.90 in each case, p < 0.05). However, H1 receptor occupancy was also highly correlated with mACh receptor occupancy among antipsychotics, so that only one of them may be critically associated with the adverse reactions. Considering that these adverse reactions have not been reported for drugs with mACh receptor antagonistic action, other than antipsychotics, the H1 receptor may contribute predominantly to the antipsychotics-induced weight gain and diabetes mellitus.

DISCUSSION/CONCLUSION

Model analysis based on receptor occupancy indicates that H1 receptor blockade is the primary cause of antipsychotics-induced weight gain and diabetes mellitus.

First-episode schizophrenia: a focus on pharmacological treatment and safety considerations

Schizophrenia is a debilitating disorder, which is usually chronic, and is one of the most devastating medical illnesses. Early and appropriate treatment with antipsychotics is an important strategy for patients with first-episode schizophrenia. However, there are many possible safety issues for patients with schizophrenia that should be considered and properly addressed. Depressive symptoms and suicidal behaviour commonly occur in first-episode schizophrenic patients, and every effort should be made to treat and minimise these symptoms. There are also important issues and considerations in young and first-episode patients that should also be considered in the emergency treatment setting and for minimising medication nonadherence in this population. Most importantly, adverse effects should be considered, minimised and addressed. While first- and second-generation antipsychotics (SGAs) both appear to offer similar efficacy for amelioration of positive symptoms in first-episode patients, SGAs may offer better tolerability, specifically regarding extrapyramidal symptoms (EPS) and tardive dyskinesia risk, and some prolactin-sparing benefits. However, these medications do cause a host of adverse effects, including weight gain, metabolic disturbances, corrected QT interval prolongation and prolactin-related adverse effects, which are important considerations relating to both the short- and long-term safety of patients with schizophrenia being treated with SGAs. Clozapine and olanzapine are most likely to cause weight gain and metabolic effects, while risperidone is more likely to cause EPS and prolactin elevations. Most antipsychotics should be used in low doses to minimise adverse effects and each medication should be optimised in a highly individualised way to maximise adherence and treatment outcomes and minimise tolerability and safety concerns. At some point in their lives, these patients will most probably experience periods of depression, suicidal behaviours, adverse effects and nonadherence, and every effort should be made to minimise or prevent these from occurring. Thus, safety concerns in this group of young patients, in the beginning of their first psychotic episode, are a major issue as they are starting a journey of antipsychotic treatment that is likely to last for the remainder of their lives.

Characterisation of olanzapine-induced weight gain and effect of aripiprazole vs olanzapine on body weight and prolactin secretion in female rats

RATIONALE

Atypical antipsychotic drug (APD)-induced weight gain causes non-compliance, increasing the risk of relapse and medical complications.

OBJECTIVES

In an animal model, we assessed body weights, food intake, body fat/lean body mass contents and blood serum levels of glucose and lipids in female rats treated with olanzapine (Experiment 1). Also, we investigated the effect of aripiprazole vs olanzapine treatment on weight gain (WG) and plasma prolactin secretion in two strains (Wistar and Sprague-Dawley) and in two housing conditions (singly and group housed; Experiment 2).

METHODS

In Experiment 1, Wistar females received either vehicle or olanzapine (5.0 mg kg(-1), p.o.) twice daily for 14 days. In Experiment 2, female rats (Wistar or Sprague-Dawley), housed singly or in groups, received either vehicle, aripiprazole (2.0-8.0 mg kg(-1), p.o.), or olanzapine (1.0-10 mg kg(-1), p.o.) twice daily for 7 days. Body weights and food intake were assessed daily. Body composition and blood assays were analyzed at the end of the treatment.

RESULTS

WG induced by chronic olanzapine treatment was characterised by hyperphagia, increased body fat, and serum free fatty acid content and reduced lean tissue and serum glucose content. Subchronic aripiprazole treatment resulted in rapid and robust WG similar to those observed with olanzapine. In spite of similar effects on body weight, aripiprazole and olanzapine stimulated markedly different patterns of prolactin secretion. Body weight changes and prolactin secretion induced by these APDs were significantly modulated by housing and by strain.

CONCLUSION

Assessment of body weight in the present model may not have predictive validity, and other measures may be needed to differentiate between WG-inducing and weight-neutral drugs.

Second-generation (atypical) antipsychotics and metabolic effects: a comprehensive literature review

Increasing numbers of reports concerning diabetes, ketoacidosis, hyperglycaemia and lipid dysregulation in patients treated with second-generation (or atypical) antipsychotics have raised concerns about a possible association between these metabolic effects and treatment with these medications. This comprehensive literature review considers the evidence for and against an association between glucose or lipid dysregulation and eight separate second-generation antipsychotics currently available in the US and/or Europe, specifically clozapine, olanzapine, risperidone, quetiapine, zotepine, amisulpride, ziprasidone and aripiprazole. This review also includes an assessment of the potential contributory role of treatment-induced weight gain in conferring risk for hyperglycaemia and dyslipidaemia during treatment with different antipsychotic medications. Substantial evidence from a variety of human populations, including some recent confirmatory evidence in treated psychiatric patients, indicates that increased adiposity is associated with a variety of adverse physiological effects, including decreases in insulin sensitivity and changes in plasma glucose and lipid levels. Comparison of mean weight changes and relative percentages of patients experiencing specific levels of weight increase from controlled, randomised clinical trials indicates that weight gain liability varies significantly across the different second generation antipsychotic agents. Clozapine and olanzapine treatment are associated with the greatest risk of clinically significant weight gain, with other agents producing relatively lower levels of risk. Risperidone, quetiapine, amisulpride and zotepine generally show low to moderate levels of mean weight gain and a modest risk of clinically significant increases in weight. Ziprasidone and aripiprazole treatment are generally associated with minimal mean weight gain and the lowest risk of more significant increases. Published studies including uncontrolled observations, large retrospective database analyses and controlled experimental studies, including randomised clinical trials, indicate that the different second-generation antipsychotics are associated with differing effects on glucose and lipid metabolism. These studies offer generally consistent evidence that clozapine and olanzapine treatment are associated with an increased risk of diabetes mellitus and dyslipidaemia. Inconsistent results, and a generally smaller effect in studies where an effect is reported, suggest limited if any increased risk for treatment-induced diabetes mellitus and dyslipidaemia during risperidone treatment, despite a comparable volume of published data. A similarly smaller and inconsistent signal suggests limited if any increased risk of diabetes or dyslipidaemia during quetiapine treatment, but this is based on less published data than is available for risperidone. The absence of retrospective database studies, and little or no relevant published data from clinical trials, makes it difficult to draw conclusions concerning risk for zotepine or amisulpride, although amisulpride appears to have less risk of treatment-emergent dyslipidaemia in comparison to olanzapine. With increasing data from clinical trials but little or no currently published data from large retrospective database analyses, there is no evidence at this time to suggest that ziprasidone and aripiprazole treatment are associated with an increase in risk for diabetes, dyslipidaemia or other adverse effects on glucose or lipid metabolism. In general, the rank order of risk observed for the second-generation antipsychotic medications suggests that the differing weight gain liability of atypical agents contributes to the differing relative risk of insulin resistance, dyslipidaemia and hyperglycaemia. This would be consistent with effects observed in nonpsychiatric samples, where risk for adverse metabolic changes tends to increase with increasing adiposity. From this perspective, a possible increase in risk would be predicted to occur in association with any treatment that produces increases in weight and adiposity. However, case reports tentatively suggest that substantial weight gain or obesity may not be a factor in up to one-quarter of cases of new-onset diabetes that occur during treatment. Pending further testing from preclinical and clinical studies, limited controlled studies support the hypothesis that clozapine and olanzapine may have a direct effect on glucose regulation independent of adiposity. The results of studies in this area are relevant to primary and secondary prevention efforts that aim to address the multiple factors that contribute to increased prevalence of type 2 diabetes mellitus and cardiovascular disease in populations that are often treated with second-generation antipsychotic medications.

Olanzapine-induced diabetes in a seven-year-old boy

The atypical antipsychotics have been recognized to induce diabetes mellitus and ketoacidosis in the adult psychiatric population. This report notes the onset of weight gain, diabetes, and apparent ketosis in a prepubertal boy diagnosed with bipolar disorder and treated with olanzapine. The hyperglycemia rapidly normalized after discontinuation of the olanzapine. Within 2 years, the diabetes recurred. In spite of the normalization of blood-glucose levels, urine ketone tests remained positive and were explained by the fact that patients taking valproic acid may have a false-positive urine test for ketones. Regular monitoring of glucose should be considered in children and adolescents who gain weight while treated with atypical antipsychotics.

Antipsychotic exposure and type 2 diabetes among patients with schizophrenia: a matched case-control study of California Medicaid claims

PURPOSE

To examine the risk of developing type 2 diabetes mellitus among people with schizophrenia exposed to atypical antipsychotics (clozapine, olanzapine, quetiapine, risperidone) compared to those exposed to conventional antipsychotics.

METHODS

A matched case-control design was used to examine California Medicaid beneficiaries. Cases developed diabetes subsequent to being diagnosed with schizophrenia (ICD-9295), were 18 years or older, and were exposed to at least one antipsychotic medication at some point during the 12 weeks preceding diabetes diagnosis. Diabetes was defined by diagnostic claim (ICD-9250) or prescription for antidiabetic agents. A total of 3663 cases were matched to 14 523 non-diabetic controls (people with schizophrenia matched on gender and age +/-5 years). All had to be continuously eligible for benefits during the 12-week period preceding diabetes onset in the case. Conditional logistic regression modeled the risk of exposure, controlling for age, ethnicity, and exposure to selected concomitant medications. Analyses were repeated with 24- and 52-week exposure windows.

RESULTS

Using a 12-week exposure window, olanzapine (OR = 1.36, 95%CI 1.20-1.53), clozapine (OR = 1.34, 95%CI 1.16-1.55), and combination atypical therapy (OR = 1.58, 95%CI 1.33-1.88), but not risperidone or quetiapine, were associated with increased odds of developing diabetes compared to conventional antipsychotics. Changing to a 24-week exposure window, the risks were: olanzapine (OR = 1.38, 95%CI 1.22-1.56), clozapine (OR = 1.32, 95%CI 1.14-1.53), or combinations (OR = 1.54, 95%CI 1.29-1.84). With a 52-week exposure window, the risks were: olanzapine (OR = 1.41, 95%CI 1.24-1.60), clozapine (OR = 1.41, 95%CI 1.21-1.65), combinations (OR = 1.58, 95%CI 1.31-1.90). Risk for olanzapine increased with dose. Hispanic, African American, and unknown ethnicity were significant risks for development of type 2 diabetes as was exposure to selected concomitant medications.

CONCLUSIONS

Exposure to olanzapine or clozapine is associated with a 34-41% increase in the developing of type 2 diabetes among California Medicaid recipients with schizophrenia. Prospective, randomized trials are needed to confirm these retrospective, observational findings.

Frequency of New-Onset Diabetes Mellitus and Use of Antipsychotic Drugs Among Central Texas Veterans

STUDY OBJECTIVES

To determine whether the frequency of new-onset diabetes mellitus differs between patients taking atypical antipsychotic agents and those taking typical agents, whether the frequency of new-onset diabetes differs among those taking the atypical antipsychotic agents, and what clinical and demographic factors influence the occurrence of new-onset diabetes.

DESIGN

Retrospective analysis.

SETTING

Central Texas Veterans Health Care System.

PATIENTS

Continuously enrolled adult (> or = 18 yrs) patients with no previous (6 mo) antipsychotic use and no history (previous 1 yr) of diabetes.

MEASUREMENTS AND MAIN RESULTS

Data from the Central Texas Veterans Health Care System were extracted from September 1995-November 2002. Clinical and demographic factors used in the analysis were antipsychotic agent taken, body mass index, diabetes-related risk factors, type of mental health comorbidity, age, sex, and race. Among those who met the inclusion criteria (3469 patients), chi2 analyses revealed no significant difference in the frequency of diabetes between the typical and atypical groups (p=0.5553) or among those taking atypical agents (p=0.6520). Multivariate logistic regression (1587 patients) revealed that increasing age (odds ratio [OR] 1.213, 95% confidence interval [CI] 1.016-1.447, p=0.0324), nonwhite race (OR 1.761, 95% CI 1.174-2.640, p=0.0062), and hyperlipidemia (OR 1.606, 95% CI 1.064-2.425, p=0.0242) were significantly related to new-onset diabetes.

CONCLUSIONS

Among veterans taking antipsychotic agents, no difference was noted in the frequency of diabetes between patients who took typical agents and those who took atypical agents. After controlling for demographic and clinical variables, still no significant difference was noted among the agents. The main factors (increasing age, nonwhite race, and hyperlipidemia) related to new-onset diabetes were those that are typically associated with the disease.

High-dose olanzapine-induced improvement of preexisting type 2 diabetes mellitus in schizophrenic patients

OBJECTIVE

During the last few years there have been numerous publications concerning glucose dysregulation and antipsychotic treatment with new-onset diabetes and exacerbation of existing disease being reported. At the same time three anecdotal reports describing decrease of blood glucose level during clozapine and olanzapine treatment were published. Here we report two cases of clinically significant dose-related reductions in glucose levels in schizophrenic and schizoaffective patients suffering from pre-existing type 2 diabetes during high dose (40 mg/day) olanzapine treatment. To the best of our knowledge, this is a first report of decreasing glucose blood levels in association with olanzapine therapy in pre-existing type 2 diabetes. Antipsychotic treatment with high doses of olanzapine showed that the relationship between olanzapine and glucose regulation is more unambiguous than usually assumed.

CONCLUSIONS

There is a need for further studies in order to define the influence of high dose olanzapine for schizophrenic and schizoaffective patients suffering from type 2 diabetes.

Differential effects of typical and atypical antipsychotics on nerve growth factor and choline acetyltransferase expression in the cortex and nucleus basalis of rats

Previously we reported that chronic exposure to haloperidol (HAL), but not the atypical antipsychotics risperidone (RISP) or clozapine (CLOZ), resulted in reductions in brain choline acetyltransferase (ChAT) immunoreactivity and impaired water maze task performance in rats. In the present study, we compared the effects of these antipsychotic drugs on the expression of nerve growth factor (NGF) as well ChAT the in the rat cortex and nucleus basalis of Meynert (NBM) in an effort to determine the underlying mechanism for the differential drug effects observed previously. We also evaluated the effects of these compounds in a crossover design to evaluate specific neurochemical consequences of switching between typical and atypical antipsychotics, a common practice observed in the clinical setting. Male Wistar rats (250-300 g) were exposed to HAL (2.0 mg/kg/day), RISP (2.5 mg/kg/day), or CLOZ (20 mg/kg/day) for 45 days or a pre-treatment regimen consisting of administering either RISP/HAL (i.e., RISP followed by HAL) or CLOZ/HAL, or a post-treatment regimen consisting of administering: HAL/RISP or HAL/CLOZ. The duration of each treatment in the crossover study was also 45 days. NGF and ChAT immunoreactivity were measured by quantitative immunohistochemistry in some sub-cerebral cortical regions and NBM after drug exposures. NGF protein was also measured by an enzyme-linked ImmunoSorbent assay (ELISA) in rat sensorimotor cortex. The results indicated that HAL (but not RISP or CLOZ) significantly reduced NGF levels in some sub-cortical regions and ChAT immunoreactivity in both cortex and NBM. However, pre-treatment with CLOZ prevented the HAL-associated decreases in NGF and ChAT, while post-treatment with either RISP or CLOZ (i.e., after the administration of HAL) appeared to restore NGF and ChAT to control levels. These data indicate that antipsychotic drugs exert dissimilar effects on the levels of NGF and ChAT in the brain, which may contribute to their differential effects on cognitive function. The crossover data further suggest that certain atypical antipsychotic drugs (e.g., clozapine) may have the potential to prevent or reverse the deleterious effects of HAL on important neurochemical substrates of cognitive function.

Reduced dopaminergic tone in hypothalamic neural circuits: expression of a "thrifty" genotype underlying the metabolic syndrome?

The thrifty genotype hypothesis postulates that the genetically determined ability to grow obese and insulin resistant in times of food abundance confers a survival advantage in times of famine. Obviously, this ability poses a major health threat in modern times, where food is always available in large quantities. In the last 10-15 years, many genes encoding pathways that orchestrate energy balance and fuel flux have been discovered. This paper summarizes the evidence that diminished dopaminergic tone in hypothalamic nuclei contributes to the "thrifty" genotype/phenotype. Reduced dopaminergic neurotransmission in the suprachiasmatic nucleus of seasonally obese animals appears to drive noradrenalin and NPY mediated transmissions in other nuclei to induce the obesity syndrome at the appropriate time of year. Treatment with dopamine D(2) receptor agonists can fully reverse the metabolic syndrome in these animals. Similar mechanisms are operative in non-seasonal obese animal models. In man, treatment with dopamine D(2) receptor antagonists induces obesity and type 2 diabetes mellitus, whereas dopamine D(2) receptor activation ameliorates the metabolic profile in obese nondiabetic and diabetic humans. Various loss of function mutations of the dopamine D(2) receptor gene are associated with overweight in humans. In concert, the data support the notion that diminution of dopaminergic (dopamine D(2) receptor mediated) transmission in relevant hypothalamic nuclei sets the stage for efficient partitioning of ingested nutrients to contribute to a phenotype that is not so thrifty anymore.

Hyperglycemia with antipsychotic treatment

Diabetes and mental disorders are common chronic illnesses in the United States. Recently, the introduction of a new class of atypical antipsychotic medications has been a major treatment advance for patients with mental disorders. Because of increased use of atypical antipsychotic medications, new and unanticipated side effects have often appeared. Treatment-emergent diabetes has been described for conventional and atypical antipsychotics. People with schizophrenia may be at increased risk for type 2 diabetes because of the side effects of antipsychotic medication, underlying predisposition, and less healthy lifestyles.

Adverse Metabolic Effects Associated with Atypical Antipsychotics

Adverse metabolic effects, such as diabetes mellitus, lipid abnormalities and weight gain, have increasingly been recognised with the use of the newer, so-called atypical antipsychotic drugs. This article reviews the current literature in the field and attempts to answer the question of whether the atypical antipsychotics differ in their effects on glucose-insulin homeostasis and lipid metabolism. It also addresses how then to manage the use of the atypical antipsychotics that do interfere with these metabolic systems. Differences in effects of atypical antipsychotics on leptin levels are also summarised and put into context; bodyweight gain associated with atypical antipsychotics is reviewed elsewhere. In summary, there are no large controlled trials published quantifying the prevalence of adverse effects on glucose-insulin homeostasis and lipid metabolism in patients receiving atypical antipsychotics. Nevertheless, the published articles and case reports reviewed in this article give a fairly good view of those adverse effects occurring with clozapine, olanzapine and risperidone, whereas little data are available regarding quetiapine, ziprasidone and zotepine, and no data exist for amisulpride and aripiprazole. Estimated rankings of the atypical agents, based on the available literature, show that the relative risk of glucose intolerance/diabetes mellitus, hyperlipidaemia and hyperleptinaemia is highest for clozapine and olanzapine, moderately high for quetiapine, rather low for risperidone and lowest for ziprasidone. Since adverse metabolic effects of atypical antipsychotics may have a negative influence on both the antipsychotic treatment outcome as well as the physical health of the patient, these effects have to be recognised and adequately managed. In this review, recommendations for prevention and treatment of the adverse metabolic effects are outlined.

Diabetes mellitus e antipsicóticos atípicos

Pacientes esquizofrênicos têm maior risco para desenvolvimento de transtorno hiperglicêmico e o uso de antipsicóticos parece ampliar o risco de desenvolvimento de diabetes mellitus. O presente trabalho é uma revisão da literatura acerca da relação entre antipsicóticos atípicos e risco de desenvolvimento de diabetes mellitus. A pesquisa bibliográfica foi realizada por meio dos bancos de dados Medline e Webofscience enfocando os seguintes tópicos: "Hyperglycemia", "Diabetes Mellitus", "Antipsychotic Agents", com o objetivo de identificar artigos originais e de revisão compreendidos entre 1997 e setembro de 2002. Conclui-se pela existência de maior risco de desenvolvimento de alterações glicídicas na população de pacientes utilizando medicamentos antipsicóticos. Medidas higieno-dietéticas e atenção aos fatores de risco devem ser levados em conta no tratamento de pacientes psicóticos.

Antipsychotic-induced type 2 diabetes: evidence from a large health plan database

Case evidence suggests that some of the atypical antipsychotics may induce type 2 diabetes. The objective of this study was to evaluate the association of antipsychotic treatment with type 2 diabetes in a large health plan database. Claims data for patients with psychosis within a health plan of nearly 2 million members were analyzed using logistic regression. Frequencies of newly treated type 2 diabetes in patients untreated with antipsychotics and among patients treated with quetiapine, risperidone, olanzapine, and conventional antipsychotics were compared. Based on exposure measured in months of antipsychotic treatment, quetiapine and risperidone patients had estimated odds of receiving treatment for type 2 diabetes that were lower than those of patients untreated with antipsychotics (not statistically significant); patients treated with conventional antipsychotics had estimated odds that were virtually equivalent to those of patients untreated with antipsychotics; olanzapine alone had odds that were significantly greater than those of patients untreated with antipsychotics (P = 0.0247). Odds ratios based on 8 months of screening for pre-existing type 2 diabetes and assuming 12 months of antipsychotic treatment were: risperidone = 0.660 (95% CI 0.311-1.408); olanzapine = 1.426 (95% CI 1.046-1.955); quetiapine = 0.976 (95% CI 0.422-2.271); and conventional antipsychotics = 1.049 (95% CI 0.688-1.613). Case reports, prospective trials, and other retrospective studies have increasingly implicated olanzapine and clozapine as causing or exacerbating type 2 diabetes. Few have implicated risperidone while evidence on quetiapine has been limited. This study supports earlier findings on risperidone versus olanzapine and builds evidence on quetiapine. Additional studies are needed to evaluate the association of antipsychotic treatment with type 2 diabetes.

Comparative study of the development of diabetes mellitus in patients taking risperidone and olanzapine

OBJECTIVES

A growing body of literature suggests that certain atypical antipsychotics, especially olanzapine and clozapine, may induce glucoregulatory dysfunction. We assessed the differences in risk of developing diabetes mellitus during treatment with olanzapine and risperidone by using patients treated with haloperidol and fluphenazine as control subjects in whom we would not expect to see an increased risk.

METHODS

We conducted a retrospective analysis of the Veteran's Integrated Service Network 10 Veterans Affairs (VA) database. Data for patients receiving olanzapine, risperidone, haloperidol, or fluphenazine from January 1, 1997-December 31, 2000, were included. Diabetes was defined as any health system encounter associated with the International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis for diabetes (250.xx) or prescription for a hypoglycemic agent. Data of patients with markers for diabetes within 1 year before their index date, female patients, racial groups other than Caucasian or African-American, and patients receiving clozapine were not analyzed. We performed a Cox regression, with antipsychotic therapy as a time-dependent covariate. Other covariates considered for inclusion in the final model were number of days supply of antipsychotic drug, age, race, psychiatric diagnoses, substance abuse, lithium, valproic acid, and other typical or atypical antipsychotic agents.

RESULTS

Data for 5837 patients were analyzed. Overall rate of developing diabetes in the study population was 6.3% (368 of 5837 patients). Olanzapine therapy was associated with a significantly higher risk of development of diabetes compared with risperidone (hazard ratio [HR] 1.37, 95% confidence interval 1.06-1.76, p=0.016) while controlling for race, age, diagnosis, substance abuse, lithium, valproic acid, and other atypical antipsychotic agents. No differences in the rate of developing diabetes were detected between fluphenazine and risperidone (HR 1.11, p=0.69), or haloperidol and risperidone (HR 0.89, p=0.41).

CONCLUSIONS

Olanzapine was associated with a 37% (HR 1.37) increased risk of development of diabetes compared with risperidone in a VA population, even after adjusting for other factors associated with the development of diabetes and temporal exposure to study drug. Because of limitations associated with database research, prospective studies should be conducted to corroborate these findings.

Alternatives to lithium and divalproex in the maintenance treatment of bipolar disorder

OBJECTIVES

The role of lithium carbonate in the maintenance treatment of bipolar disorder is well established. Unfortunately, many patients fail to respond adequately to this agent or are unable to tolerate its adverse effects. Divalproex has become a commonly used alternative to lithium, but it also is ineffective or poorly tolerated in many patients. This article attempts to review the available data on maintenance therapy in bipolar disorder with a variety of anticonvulsants and antipsychotics (both conventional and novel), with reference to relevant studies in acute mania and bipolar depression as well.

METHODS

Evidence on maintenance therapy and relevant acute-phase data were collected using MEDLINE database searches.

RESULTS

Data on maintenance therapy with agents other than lithium and divalproex are sparse, and often derived from open, uncontrolled studies. Implications and flaws of available data are discussed.

CONCLUSIONS

Other than lithium, there are few robust double-blind data to support the use of a variety of agents in the maintenance phase. However, uncontrolled data suggest that a number of agents merit further study.

Glucose intolerance with atypical antipsychotics

BACKGROUND

Previous studies have suggested that the atypical antipsychotics clozapine and olanzapine may be associated with an increased risk of glucose intolerance and diabetes mellitus. Early studies have also suggested an association between use of conventional antipsychotics and the development of glucose intolerance.

OBJECTIVE

To examine quantitatively the association between glucose intolerance including diabetes mellitus and the use of the atypical antipsychotics clozapine, olanzapine or risperidone, and to identify possible risk factors for the development of glucose intolerance during treatment with these drugs.

METHODS

All reports suggestive of glucose intolerance for clozapine, olanzapine and risperidone were identified in the WHO database for adverse drug reactions. In the analyses of possible risk factors for glucose intolerance all other reports of adverse drug reactions for clozapine, olanzapine and risperidone were used as reference. Using the Bayesian Confidence Propagation Neural Network method, the strengths of the associations over time between glucose intolerance and the use of these drugs were analysed. For comparison, the strengths of the associations between glucose intolerance and the use of the conventional antipsychotics haloperidol and chlorpromazine were also analysed.

RESULTS

Clozapine, olanzapine and risperidone were significantly associated with glucose intolerance. In contrast, chlorpromazine and haloperidol were not associated with glucose intolerance. For clozapine, olanzapine and risperidone grouped together, the following potential risk factors for glucose intolerance were identified: an underlying diabetic condition (odds ratio [OR] 10.22, 95% CI 8.20-12.73), an increase in weight (OR 2.36, 95% CI 1.76-3.17), male gender (OR 1.27, 95% CI 1.11-1.47), and concomitant use of valproic acid (OR 1.97, 95% CI 1.61-2.40), selective serotonin reuptake inhibitors (OR 1.63, 95% CI 1.33-1.99) or buspirone (OR 2.24, 95% CI 1.33-3.77).

CONCLUSION

Treatment with clozapine, olanzapine or risperidone appears to be associated with an increased risk of glucose intolerance.

Differential effects of antipsychotic agents on the risk of development of type 2 diabetes mellitus in patients with mood disorders

BACKGROUND

Atypical antipsychotics are being used increasingly in the management of mood disorders.

OBJECTIVE

The objective of this study was to investigate the association between exposure to antipsychotic therapy and newly reported type 2 diabetes mellitus in patients with mood disorders.

METHODS

Claims data for the period January 1996 through December 1997 were analyzed for patients with mood disorders in 2 large US health plans. Logistic regression models were used to determine the odds of reporting diabetes in patients exposed to risperidone, olanzapine, or high- or low-potency conventional antipsychotics compared with untreated patients, taking into account duration of treatment and dosage. Some of the covariates used in the models were concurrent use of antipsychotics, use of other psychotropic drugs, age, sex, and length of observation.

RESULTS

Based on the claims data, 849 patients were exposed to risperidone, 656 to olanzapine, 785 to high-potency conventional antipsychotics, and 302 to low-potency conventional antipsychotics; 2644 patients were untreated. The odds of newly reported type 2 diabetes in patients who received risperidone were not significantly different from those in untreated patients (12-month odds ratio [OR] = 1.024; 95% CI, 0.351-3.015). The odds in patients treated with high-potency conventional antipsychotics also did not differ significantly from those of untreated patients (12-month OR = 1.945; 95% CI, 0.794-4.786). Unlike patients who received risperidone or high-potency conventional antipsychotics, patients who received olanzapine (12-month OR = 4.289; 95% CI, 2.102-8.827) and low-potency conventional antipsychotics (12-month OR = 4.972; 95% CI, 1.967-12.612) had significantly higher odds for the development of type 2 diabetes compared with untreated patients.

CONCLUSIONS

These findings suggest that some antipsychotics may increase the risk for the development of type 2 diabetes in patients with mood disorders and that the effect may vary by drug. In contrast to olanzapine and low-potency conventional antipsychotics, risperidone and high-potency conventional antipsychotics were not associated with an increased risk for development of type 2 diabetes in this patient population.

Diabetes mellitus associated with atypical anti-psychotic medications

Diabetes or hyperglycemia associated with the use of atypical anti-psychotic agents is a subject of growing concern among health care providers and the patients who use the drugs. Although much attention has been relegated to this topic in the mental health literature, there has been little attention devoted to it in the diabetes literature. The purpose of this report is to review the problem of diabetes mellitus associated with atypical anti-psychotic use from an endocrinology perspective. This paper will specifically present (a) a review of the increased prevalence of diabetes in the setting of schizophrenia, (b) a compilation and critical assessment of the existing publications that have documented the association of hyperglycemia and atypical anti-psychotic use, (c) a discussion of the potential mechanisms through which antipsychotics may lead to disturbances in glucose homeostasis, and (d) recommendations for the effective monitoring and treatment of affected patients.

Cataract Occurrence With Antipsychotic Drugs

Chlorpromazine and several other phenothiazine neuroleptic drugs appear to induce cataract formation. However, the newer generation of antipsychotic agents has shown no evidence of an etiologic relationship with cataract occurrence. Research did reveal cataract occurrence in dogs who received quetiapine, which prompted concern despite there being no known causal link between quetiapine and lens opacities in humans. Nevertheless, quetiapine's manufacturer issued formal recommendations for ophthalmological follow-up examinations with the use of this drug. Infrequent occurrences of cataract development have been documented in people taking olanzapine but, again, without established causative association; a similar situation is seen with ziprasidone. Periodic ocular examinations of the lens are suggested for patients prescribed long-term treatment with phenothiazines or quetiapine.

Assessment of independent effect of olanzapine and risperidone on risk of diabetes among patients with schizophrenia: population based nested case-control study

OBJECTIVE

To quantify the association between olanzapine and diabetes.

DESIGN

Population based nested case-control study.

SETTING

United Kingdom based General Practice Research Database comprising 3.5 million patients followed between 1987 and 2000.

PARTICIPANTS

19 637 patients who had been diagnosed as having and treated for schizophrenia. 451 incident cases of diabetes were matched with 2696 controls.

MAIN OUTCOME MEASURES

Diagnosis and treatment of diabetes.

RESULTS

Patients taking olanzapine had a significantly increased risk of developing diabetes than non-users of antipsychotics (odds ratio 5.8, 95% confidence interval 2.0 to 16.7) and those taking conventional antipsychotics (4.2, 1.5 to 12.2). Patients taking risperidone had a non-significant increased risk of developing diabetes than non-users of antipsychotics (2.2, 0.9 to 5.2) and those taking conventional antipsychotics (1.6, 0.7 to 3.8).

CONCLUSION

Olanzapine is associated with a clinically important and significant increased risk of diabetes.

Olanzapine-associated diabetes mellitus

STUDY OBJECTIVE

To explore the clinical characteristics of hyperglycemia in patients treated with olanzapine.

DESIGN

Retrospective, epidemiologic survey of spontaneously reported adverse events related to olanzapine therapy

SETTING

Government-affiliated drug evaluation center.

PATIENTS

Two hundred thirty-seven patients with olanzapine-associated diabetes or hyperglycemia.

INTERVENTION

One hundred ninety-six cases from January 1994-May 15, 2001, were identified with the United States Food and Drug Administration's MedWatch Drug Surveillance System, and 41 cases published through May 15, 2001, were identified with MEDLINE or through meeting abstracts.

MEASUREMENTS AND MAIN RESULTS

Of the 237 cases, 188 were new-onset diabetes, 44 were exacerbations of preexistent disease, and 5 could not be classified. Mean patient age for newly diagnosed cases was 40.7+/-12.9 years and male:female ratio was 1.8. Seventy-three percent of all cases of hyperglycemia appeared within 6 months of start of olanzapine therapy. Eighty patients had metabolic acidosis or ketosis, 41 had glucose levels of 1000 mg/dl or greater, and 15 patients died. When olanzapine was discontinued or the dosage decreased, 78% of patients had improved glycemic control. Hyperglycemia recurred in 8 of 10 cases with rechallenge.

CONCLUSIONS

Number of reports, temporal relationship to start of olanzapine therapy, relatively young age, and improvement on drug withdrawal suggest that olanzapine may precipitate or unmask diabetes in susceptible patients.

Atypical antipsychotic-induced diabetes mellitus: how strong is the evidence?

Atypical antipsychotics offer significant improvements over older, conventional antipsychotic agents. However, recently the newer agents have been linked to medical morbidity including hyperglycaemia, diabetes mellitus, bodyweight gain and abnormal lipid levels. Even more concerning, because of a significant risk of death, there have been numerous case reports of patients treated with clozapine or olanzapine developing diabetic ketoacidosis shortly after initiation of the drug. Much of the information concerning the medical morbidity of diabetes mellitus is based on case reports, retrospective chart reviews, naturalistic studies and cross-sectional studies. While definitive studies have yet to be reported, mounting evidence suggests that the atypical antipsychotic agents, particularly clozapine and olanzapine, may significantly impair glucose metabolism and increase the risk of diabetes in patients with schizophrenia. Diabetic ketoacidosis, although it appears to be uncommon, is of great concern secondary to the risk of death. Patients treated with atypical antipsychotic agents should be routinely screened for diabetes and other metabolic abnormalities including raised lipid levels. Patients with risk factors for diabetes should be monitored more closely. Reports and clinical experience suggest that in a case of atypical antipsychotic-associated diabetes or diabetic ketoacidosis, discontinuation of the antipsychotic agent may result in complete resolution of the hyperglycaemia and diabetes.