Risperidone-associated new-onset diabetes

Retrospective analysis of risk factors in patients with treatment-emergent diabetes during clinical trials of antipsychotic medications

Aims

In this retrospective analysis, we assessed the short-term risk of treatment-emergent diabetes (TED) among patients with schizophrenia during clinical trials of antipsychotic medications.

Method

From a non-diabetic cohort of patients with schizophrenia (n=5013), the relationship between baseline non-fasting glucose measurement, presence at baseline of risk factors for diabetes, weight gain and therapy assignment on the risk of treatment-emergent diabetes were assessed.

Results

At the baseline assessment, about a third of patients identified with TED during treatment had non-fasting glucose levels over 7.8 mmol/l and two-thirds had multiple diabetes risk factors. Both baseline non-fasting glucose level and the presence of multiple pre-existing diabetes risk factors appeared to have a major impact on the risk of developing diabetes.

Conclusions

Overall, risk factors for diabetes in patients with schizophrenia overlap those in the general population. The results also suggest that many patients identified with TED might have had pre-existing glycaemic abnormalities or a high baseline burden of diabetes risk factors.

Treatment of Diabetic Ketoacidosis Associated With Antipsychotic Medication: Literature Review

BACKGROUND

The second-generation antipsychotics (SGAs) are associated with metabolic disturbances. Diabetic ketoacidosis (DKA) is a rare, but potentially fatal sign of acute glucose metabolism dysregulation, which may be associated with the use of SGAs. This study aims to review published reports of patients with schizophrenia and antipsychotic drug-associated DKA, focusing on the effective management of both conditions.

METHODS

Using a predefined search strategy, we searched PubMed and EMBASE from their inception to July 2016. The search terms were related to "diabetic ketoacidosis" and "antipsychotic medication." Case reports, case series, and reviews of case series written in English language were included in the review.

RESULTS

Sixty-five reports were analyzed. In most patients who developed antipsychotic-associated DKA, 1 or more suspected antipsychotic medications were discontinued. In 5 cases, a rechallenge test was trialed, and in only 1 case, it resulted in the elevation of blood glucose. The majority was subsequently treated with a different SGA in combination with insulin/oral hypoglycemic agents; although approximately a third of patients had a complete resolution of symptoms or could control diabetes with diet only at the point of discharge.

CONCLUSIONS

Patients taking antipsychotic medications should be regularly screened for insulin resistance and educated about potential complications of antipsychotic medications. This will allow clinicians to individualize treatment decisions and reduce iatrogenic contribution to morbidity and mortality. To achieve best treatment outcomes, antipsychotic-induced DKA should be treated jointly by psychiatry and endocrinology teams.

A Randomized, Controlled Multisite Study of Behavioral Interventions for Veterans with Mental Illness and Antipsychotic Medication-Associated Obesity

BACKGROUND

Weight gain and other metabolic sequelae of antipsychotic medications can lead to medication non-adherence, reduced quality of life, increased costs, and premature mortality. Of the approaches to address this, behavioral interventions are less invasive, cost less, and can result in sustained long-term benefits.

OBJECTIVE

We investigated behavioral weight management interventions for veterans with mental illness across four medical centers within the Veterans Affairs (VA) Healthcare System.

DESIGN

We conducted a 12-month, multi-site extension of our previous randomized, controlled study, comparing treatment and control groups.

PARTICIPANTS

Veterans (and some non-veteran women) diagnosed with mental illness, overweight (defined as having a BMI over 25), and required ongoing antipsychotic therapy.

INTERVENTIONS

One group received "Lifestyle Balance" (LB; modified from the Diabetes Prevention Program) consisting of classes and individual nutritional counseling with a dietitian. A second group received less intensive "Usual Care" (UC) consisting of weight monitoring and provision of self-help.

MAIN MEASURES

Participants completed anthropometric and nutrition assessments weekly for 8 weeks, then monthly. Psychiatric, behavioral, and physical assessments were conducted at baseline and months 2, 6, and 12. Metabolic and lipid laboratory tests were performed quarterly.

KEY RESULTS

Participants in both groups lost weight. LB participants had a greater decrease in average waist circumference [F(1,1244) = 11.9, p < 0.001] and percent body fat [F(1,1121) = 4.3, p = 0.038]. Controlling for gender yielded statistically significant changes between groups in BMI [F(1,1246) = 13.9, p < 0.001]. Waist circumference and percent body fat decreased for LB women [F(1,1243) = 22.5, p < 0.001 and F(1,1221) = 4.8, p = 0.029, respectively]. The majority of LB participants kept food and activity journals (92%), and average daily calorie intake decreased from 2055 to 1650 during the study (p < 0.001).

CONCLUSIONS

Behavioral interventions specifically designed for individuals with mental illness can be effective for weight loss and improve dietary behaviors. "Lifestyle Balance" integrates well with VA healthcare's patient-centered "Whole Health" approach. ClinicalTrials.gov identifier NCT01052714.

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.

Recent evidence and potential mechanisms underlying weight gain and insulin resistance due to atypical antipsychotics

OBJECTIVE

Atypical antipsychotics (AAPs) promote obesity and insulin resistance. In this regard, the main objective of this study was to present potential mechanisms and evidence concerning side effects of atypical antipsychotics in humans and rodents.

METHOD

A systematic review of the literature was performed using the MEDLINE database. We checked the references of selected articles, review articles, and books on the subject.

RESULTS

This review provides consistent results concerning the side effects of olanzapine (OL) and clozapine (CLZ), whereas we found conflicting results related to other AAPs. Most studies involving humans describe the effects on body weight, adiposity, lipid profile, and blood glucose levels. However, it seems difficult to identify an animal model replicating the wide range of changes observed in humans. Animal lineage, route of administration, dose, and duration of treatment should be carefully chosen for the replication of the findings in humans.

CONCLUSIONS

Patients undergoing treatment with AAPs are at higher risk of developing adverse metabolic changes. This increased risk must be taken into account when making decisions about treatment. The influence of AAPs on multiple systems is certainly the cause of such effects. Specifically, muscarinic and histaminergic pathways seem to play important roles.

The insulin sparing effect of telmisartan in a case of type 2 diabetes mellitus associated with schizophrenia under treatment of risperidone

A male patient was diagnosed with diabetes mellitus at age 37 and insulin treatment was introduced at age 49. About 2 years after the introduction of insulin, the antihypertensive agent was switched from candesartan (4 mg/day) to telmisartan (20 mg/day). The alteration improved his glycemic control dramatically, with the HbA1c levels decreasing from 8.3% to 6.0% in 6 months. Gradual marked reduction in insulin requirement was observed as it was reduced from 62 U/day to 46 U/day in 6 months and to 18 U/day in 15 months. Also his body weight was reduced from 81 kg to 65 kg in 15 months without remarkable life-style modification. Throughout the whole clinical course mentioned above, he was under treatment for schizophrenia with drugs including risperidone which possibly affects glucose metabolism. The medication for schizophrenia was not changed during this period. We present here the marked glycemia improvement effect and insulin sparing effect of telmisartan in a case of type 2 diabetes mellitus.

Treatment of bipolar disorders and metabolic syndrome: implications for primary care

Recognition of the prevalence of mood disorders and increased availability of medication options have led to calls for treating bipolar disorders in the primary care setting. Second-generation antipsychotic medications (SGAs) were initially lauded for treating bipolar disorders because of their efficacy and perceived safety relative to first-generation antipsychotic medications. Metabolic syndrome is a constellation of risk factors for cardiovascular disease and type 2 diabetes mellitus, which may emerge when treating bipolar disorders with SGAs. We conducted a search of the research literature examining the association between different SGAs and metabolic syndrome. Based on our review, we offer guidelines for monitoring patient status regarding metabolic syndrome and for providing interventions to promote healthy diet and exercise.

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.

Effects of risperidone on glucose metabolism in Chinese patients with schizophrenia: a prospective study

BACKGROUND

While most of the second generation antipsychotic agents are associated with abnormal glucose metabolism, previous studies have shown that risperidone has relatively little effect upon blood glucose levels. This study aimed to explore the effect of risperidone on the glucose-regulating mechanism of patients with schizophrenia by using the oral glucose tolerance test (OGTT), measuring insulin and C-peptide levels.

METHODS

Thirty inpatients with schizophrenia taking risperidone were studied. All the patients were given a simplified OGTT at baseline and six weeks after treatment. Plasma glucose, insulin, and C-peptide concentrations were measured at fasting, then 1 and 2h after OGTT respectively. Other data, including demographic characteristics and plasma drug concentrations, were also recorded.

RESULTS

(1) There was no significant increase in the proportion of patients demonstrating abnormal plasma glucose levels compared with baseline (p=1.000, McNemar test); (2) risperidone was associated with elevated insulin concentrations (p=0.013), C-peptide levels (p=0.020), insulin/glucose ratio (p=0.020) and BMI (p<0.01); (3) no sex differences in glucose-related measures were observed.

CONCLUSION

Risperidone treatment may be associated with alterations in glucose-regulating mechanisms in patients with schizophrenia.

Weight development in patients treated with risperidone: a 5-year naturalistic study

OBJECTIVE

To examine annual weight-development in a sample of 215 psychotic patients treated with risperidone over 5 years.

METHOD

Naturalistic longitudinal study.

RESULTS

The sample was more obese than the general population at baseline, but also increased much more in mean body mass index over approximately the same time period, while patients off medication seemed to remain weight stable. Excessive weight gain (>7%) was experienced by 40.2% and was weakly associated with weight at baseline (beta = -0.2%; P = 0.02), while independent of gender, symptoms, years of illness, prolactin levels and nicotine consumption. In patients with complete weight data (n = 87), approximately 72% (3.4 +/- 8.3 kg) of the observed 5 years weight gain (4.7 +/- 11.6 kg) had been accumulated after 2 years.

CONCLUSION

Antipsychotic drug treatment resulted in significant weight gain, which levelled off over time. Unfortunately, few significant predictors of adverse weight development could be identified, leaving little guidance for clinical decision making regarding this specific side-effect.

An open-label study of olanzapine in children and adolescents with schizophrenia

The purpose of this open-label study was to evaluate the use of olanzapine in the treatment of children and adolescents with schizophrenia. Sixteen children who were 8-17 years of age and met DSM-IV criteria for schizophrenia were admitted into a 10-week, open-label, optimizing dose study of olanzapine. The Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS), and the Clinical Global Impression (CGI)-Severity/Improvement scales were used to assess improvement during the study. Of the 16 subjects who completed the study, 12 demonstrated significant improvement on end of treatment BPRS, CGI, and PANSS scores compared with baseline. Male subjects showed greater improvement and also gained more weight. Weight gain occurred in all but 2 subjects. Weight gain was significant, with patients averaging a gain of about 6.2 kg during the 6-week course of the study. Two of the subjects experienced extrapyramidal symptoms. The average dose of olanzapine for all subjects was 0.17 mg/kg.

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.

Diabetes mellitus and antipsychotic treatment in the United Kingdom

OBJECTIVE

Treatment-emergent diabetes has been reported during exposure to conventional and atypical antipsychotics. This retrospective cohort study explored the UK General Practice Research Database (GPRD) to determine hazard ratios of diabetes for patients prescribed antipsychotics.

METHODS

A Cox proportional hazard regression model using age, gender, and obesity (BMI > 30 kg/m2) was used to determine the hazard ratio (HR) of diabetes development in conventional antipsychotic (N = 59,089), atypical antipsychotic (N = 9053), individual antipsychotic, and general patient population cohorts (N = 1,491,548).

RESULTS

Compared with the general GPRD patient population, patients exposed to conventional or atypical antipsychotics had a higher risk of developing diabetes (atypical antipsychotic cohort: HR = 2.9, CI = 2.0-4.4; and conventional antipsychotic cohort: HR = 1.9, CI = 1.6-2.3). The risk of developing diabetes during thioridazine, risperidone, or olanzapine treatment was significantly higher compared with the general GPRD patient population.

CONCLUSION

Consistent with other epidemiology studies, this study supports an increased risk of developing diabetes during treatment with antipsychotics.

[Therapy with antipsychotic drugs as a risk factor for diabetes in schizophrenia: a case-control study]

BACKGROUND AND OBJECTIVES

Atypical antipsychotics have been related with hyperglycaemia, diabetes mellitus, weight gain and lipid alterations in some patients. This study analyzed whether continuous treatment with risperidone, olanzapine, or clozapine entails a risk of glucose or lipid metabolism alterations in schizophrenic patients.

PATIENTS AND METHOD

Patients included in this study were schizophrenics who had received mono-therapeutic with clozapine, olanzapine or risperidone for a period of 1 to 3 years. Those schizophrenic patients who were diagnosed as diabetic during psychiatric treatment and those who showed fasting glycemia greater than or equal to 126 mg/dl in two consecutive measurements were considered cases. The remaining schizophrenic patients who were receiving treatment and did not show these alterations were considered controls.

RESULTS

In the adjusted analysis (multivariate logistic regression) of the effect of antipsychotic treatment on the presence of diabetes, which also assessed age and body-mass index, the adjusted odds ratio (OR) for olanzapine relative to risperidone was 2.22 (95% confidence interval [CI], 1.12-4.22), (p = 0.0228); and that for clozapine relative to risperidone was 2.87 (95% CI, 1.19, 6.93), (p = 0.0192). Both results reveal a significantly greater risk for the appearance of diabetes mellitus in patients treated with olanzapine or clozapine than in those treated with risperidone. There were significant differences in the risk of increase in triglycerides in patients receiving olanzapine (OR = 1.34; p = 0.0075) and clozapine (OR = 1.58; p = 0.0028).

CONCLUSIONS

The risk of the appearance of diabetes mellitus in patients treated with olanzapine is twice as high as that in patients treated with risperidone, and the risk in patients treated with clozapine is nearly triple as high as that found in patients treated with risperidone. Risperidone appears to be a safer antipsychotic drug in the long term, with regard to the risk of alterations in glucose and lipid metabolism.

Schizophrenia and increased risks of cardiovascular disease

OBJECTIVE

The aim of the study is to review the absolute and relative impacts of the major causes for premature mortality among patients with schizophrenia.

DATA SOURCES

We reviewed published articles on causes of mortality in the general population as well as among patients with schizophrenia.

STUDY SELECTION

We selected articles which published total and cause-specific mortality rates.

DATA EXTRACTION

We reviewed the causes of mortality and their risk factors.

DATA SYNTHESIS

The average life expectancy of the general population is 76 years (72 years in men, 80 years in women), whereas the corresponding figure is 61 years (57 years in men, 65 years in women) among patients with schizophrenia. Thus, patients with schizophrenia have approximately a 20% reduced life expectancy compared with the general population. Although patients with schizophrenia are 10 to 20 times more likely than the general population to commit suicide, more than two thirds of patients with schizophrenia, compared with approximately one-half in the general population, die of coronary heart disease (CHD). The chief risk factors for this excess risk of death are cigarette smoking, obesity leading to dyslipidemia, insulin resistance and diabetes, and hypertension.

CONCLUSIONS

The chief cause of excess premature mortality among patients with schizophrenia is CHD, caused mainly by their adverse risk factor profile. Because patients with schizophrenia have less access to medical care, consume less medical care, and are less compliant with their regimens, the choice of antipsychotic drug regimens that do not further adversely affect their risk factor for CHD is a major clinical and public health challenge among patients with schizophrenia.

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.

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.

[Assessment of metabolic impairments inducted by atypical antipsychotics among schizophrenic patients]

Conventional and atypical antipsychotics are known to induce weight gain, cause glucose and lipid impairments among schizophrenic patients. These impairments contribute to the intrinsic risk factors linked to the psychiatric pathology (sedentary state, nicotin addiction, diabetes) increasing numbers of cardiovascular complications. We propose to study ponderal modifications and presence of metabolic abnormalities in a population of schizophrenic patients treated by conventional or atypical antipsychotics, depending on the received treatment; 32 patients, whose schizophrenia diagnosis had been previously made, were consecutively included over a 4 months period. They were divided into three groups: patients treated by conventional antipsychotics (n = 6), by atypical antipsychotics (n = 16) or by a combination of both (n = 10); 6 patients (18%) display overweight problems, 4 patients (12.5%) got hypertriglyceridemia and 4 other patients (12.5%) have hypercholesterolemia. No particular drug could be directly targeted, partly because of the restricted size of our sample, but the patients presenting metabolism impairment were treated by atypical antipsychotic. The observance of these abnormalities is reflected in publications and lead to some antipsychotic treatments monitoring rules.

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.

Atypical antipsychotic agents and increased risk of diabetes: class action or differential action?

Atypical antipsychotic (AAP) agents are useful in treating patients with schizophrenia and other psychosis. Their advantages are the low incidence of extrapyramidal side effects, and possible amelioration of negative, cognitive and mood symptoms. Occurrence of diabetes after AAP drug administration is of concern as patients do not often recognise their symptoms, physicians may fail to diagnose early, with consequent morbidity and mortality. The symptoms of psychosis, including lack of insight and motivation, may decrease the ability of schizophrenic patients to communicate potential health problems. Whether or not AAP drugs induce diabetes and, if they do, if it is a class action or a differential action, is often debated. Clinical evidence on AAP drug-induced diabetes is mounting. With their discontinuation, the diabetes often dissipates, but reappears when they are started again, thereby implicating the AAP drugs in the development of diabetes. There is still dispute regarding the differential effect of the various AAP drugs in their ability to produce diabetes. Although not scientifically proven, available evidence seems to indicate that clozapine and olanzapine may have a higher propensity to induce diabetes compared with other AAP drugs.

A retrospective chart review of the clinical effects of atypical antipsychotic drugs on glycemic control in institutionalized patients with schizophrenia and comorbid diabetes mellitus

BACKGROUND

The association between schizophrenia and onset of type 2 diabetes mellitus (DM) is well documented. It is unclear whether this association is due to inherent risk factors in individuals with schizophrenia or to treatment with antipsychotic drugs, particularly atypical antipsychotic agents.

OBJECTIVES

The goals of this retrospective, observational study were the following: (1) to determine whether adequate glycemic control could be achieved in patients with schizophrenia and comorbid DM who were undergoing treatment with atypical antipsychotic drugs, (2) to identify inherent risk factors that may affect glycemic control in this patient population, and (3) to consider the possibility that combined medication and inherent risk factors may affect glycemic control.

METHODS

This was a retrospective, observational chart review that evaluated institutionalized patients in a New Jersey mental institution with concurrent diagnoses of schizophrenia and type 1 or 2 DM who were being treated with atypical antipsychotic agents (ie, olanzapine, risperidone, clozapine, or quetiapine) and were referred by their hospital internists to a weekly, half-day, in-hospital DM clinic. All patients with initial and end-point data for the efficacy measure (ie, change in glycosylated hemoglobin [HbA(1c)]) were included in the analysis. Mixed-effects linear and least-squares models were used to test whether a specific comorbidity had an effect on the change in HbA(1c) adjusted for the duration of the observation.

RESULTS

A total of 72 patients met entry criteria. Among the 38 patients with baseline and end-point data (20 treated with olanzapine and 18 treated with risperidone), mean (SD) HbA(1c) decreased from 8.21% (2.4%) to 7.62% (1.7%). The only baseline demographic characteristic or comorbidity that predicted significant worsening in the adjusted HbA(1c) change was hepatitis (P = 0.003).

CONCLUSIONS

Using appropriate, aggressive antidiabetic therapy, glycemic control was achieved in this group of patients with schizophrenia and comorbid DM who were treated with atypical antipsychotic agents.

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.

Diabetes mellitus among parkinsonian patients treated chronically with clozapine

Clozapine is the gold standard treatment for Parkinson's disease (PD) psychosis based on double blinded, placebo controlled trials, and has also been shown to alleviate tremor and dyskinesia. There is accumulating data suggesting that clozapine may be associated with increased frequency of diabetes mellitus (DM) compared to conventional neuroleptic drugs in treating schizophrenia. Forty-four predominantly geriatric parkinsonian subjects on clozapine for psychosis, tremor or dyskinesia, on an average dose of 50.6 mg/d for a mean duration of 41 months were reviewed. The prevalence of DM in this cohort was 18.1% (8/44). This rate was similar to that reported in the aged-matched general population (prevalence = 19.3% for ages > or = 60 years). In this small study, parkinsonian patients on long-term, low dose clozapine were not at increased risk for developing DM. Larger controlled prospective studies are needed to confirm this.

Weight gain and new onset diabetes associated with olanzapine and risperidone

OBJECTIVE

To assess whether newer antipsychotic medications are associated with weight gain and development of diabetes.

DESIGN

Retrospective cohort study.

SETTING

Data from a comprehensive electronic medical record serving an urban public hospital and a citywide network of mental health clinics.

PATIENTS/PARTICIPANTS

Three thousand one hundred fifteen patients at least 18 years old who were prescribed a single antipsychotic drug for at least 1 year.

METHODS

We identified independent predictors of significant weight gain (> or =7%) and new onset of diabetes mellitus in the first year of antipsychotic drug treatment, using logistic regression adjusted for demographic characteristics, obesity, preexisting psychiatric diagnoses, alcohol and drug abuse, number of primary care, psychiatric clinic, and emergency department visits, and pretreatment weight.

MEASUREMENTS AND MAIN RESULTS

Twenty-five percent of patients taking older phenothiazines developed significant weight gain in the first year of treatment compared to 40% of the patients taking olanzapine (adjusted odds ratio [OR], 2.8; 95% confidence interval [CI], 1.7 to 4.6; P <.0001) and 37% of patients taking risperidone (adjusted OR, 2.3; 95% CI, 1.5 to 3.4; P <.0001). New diabetes developed in 3% of patients taking older phenothiazines was new onset diabetes compared to 8.0% of patients taking olanzapine (adjusted OR, 1.9; 95% CI, 1.1 to 3.3; P=.03) and 3.5% of patients taking risperidone (adjusted OR, 0.7; 95% CI, 0.4 to 1.4; P=.3). No association was found between significant weight gain and developing diabetes (adjusted OR, 0.7; 95% CI, 0.4 to 1.4; P=.4).

CONCLUSIONS

Olanzapine and risperidone use was associated with gaining weight in the first year, but only olanzapine was associated with developing diabetes mellitus.

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.

Weight gain associated with atypical antipsychotic use in children and adolescents: prevalence, clinical relevance, and management

Atypical antipsychotics are increasingly prescribed to children and adolescents with neuropsychiatric disorders. Although their profile of potent antagonism at specific serotonin and dopamine receptors offers certain advantages compared with typical antipsychotics, their use has been associated with various adverse effects, including significant weight gain. This adverse effect is of particular concern in children and adolescents, secondary to the immediate and long-term health risks associated with weight gain, including obesity, diabetes mellitus, and hyperlipidemia. Indeed, from 1963 to 1991, the prevalence of obesity has approximately doubled in youth. Prior to selecting an atypical antipsychotic, a detailed review of the predictors of weight gain is necessary for every child and adolescent. Published data suggest that clozapine and olanzapine are associated with considerable weight gain, whereas risperidone and quetiapine have a moderate risk. Alternatively, ziprasidone and aripiprazole may exhibit a low risk for this adverse effect. Whereas behavioral and pharmacologic measures are available to manage weight gain associated with atypical antipsychotics, research is needed to establish more effective and safe interventions for this adverse effect in children and adolescents.

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.

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.

Hyperglycemia and hypertriglyceridemia in real world patients on antipsychotic therapy

There have been recent reports in the psychiatric literature of the possible association of glucose dysregulation and diabetes mellitus with the use of atypical antipsychotics. This article describes a retrospective chart review of patients from various clinical settings, including a continuing day treatment program, two inpatient programs, and a large private practice. Information was obtained with regard to weight, fasting blood glucose, lipid profiles, EKG changes, and medical comorbidities. The patients included those treated with conventional antipsychotic agents, clozapine, risperidone, olanzapine, and quetiapine. No one antipsychotic agent was associated with a statistically significantly higher prevalence of diabetes, lipid abnormalities, or EKG problems. It was noted, however, that there were higher rates of diabetes (17%), lipid abnormalities (43%), and hypertension (30%) across the sample. This finding suggests that the high prevalence of diabetes, lipid abnormalities, and hypertension in a young, chronically psychiatrically ill population makes the case for aggressive screening.

Treatment of schizophrenia: preventing the progression of disease

Atypical antipsychotic drugs offer a number of advantages compared with typical antipsychotic drugs during the acute treatment of psychotic episodes and maintenance treatment to prevent psychotic relapses in patients with schizophrenia. These advantages include superior efficacy, especially for negative symptoms and reduced extrapyramidal adverse effects. Clinicians, however, need to be vigilant regarding new adverse effects that may be more strongly associated with atypical than typical drugs, especially those related to weight gain. Despite increased pill costs for atypical antipsychotic drugs, the overall costs of providing care to patients with schizophrenia using these drugs do not appear to be substantially higher.

Risperidone-associated diabetes mellitus: a pharmacovigilance study

STUDY OBJECTIVE

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

DESIGN

Pharmacovigilance survey of spontaneously reported adverse events in risperidone-treated patients, with reports of haloperidol-associated hyperglycemia used as a control.

SETTING

Government-affiliated drug evaluation center.

INTERVENTION

The Food and Drug Administration MedWatch surveillance program was queried (risperidone, 1993-February 2002; haloperidol, late 1970s-February 2002) and results pooled with published cases.

MEASUREMENTS AND MAIN RESULTS

We identified 131 reports of risperidone-associated hyperglycemia in addition to seven reports of patients with hyperglycemia who received combined risperidone-haloperidol therapy and six reports of acidosis that occurred in the absence of hyperglycemia. We found 13 reports of haloperidol-associated hyperglycemia and 11 reports of acidosis without hyperglycemia. Of the reports of risperidone-associated hyperglycemia (monotherapy), 78 patients had newly diagnosed hyperglycemia, 46 had exacerbated preexisting diabetes, and 7 could not be classified. Mean +/- SD age was 39.8 +/- 17.4 years (range 8-96 yrs). Patients with new-onset diabetes (mean +/- SD age 34.8 +/- 15.7 yrs) were younger than those with preexisting diabetes (mean +/- SD age 48.8 +/- 17.5 yrs). The overall male:female ratio was 1.5. In most patients, hyperglycemia appeared within 3 months of the start of risperidone therapy. Severity of disease ranged from mild glucose intolerance to diabetic ketoacidosis or hyperosmolar coma. Twenty-six patients with acidosis or ketosis were reported. Four patients died.

CONCLUSION

Atypical antipsychotic treatment may unmask or precipitate hyperglycemia. Although such cases attributed to clozapine or olanzapine are more numerous than those associated with risperidone, the number for risperidone-associated hyperglycemia is relatively higher than that observed with the conventional neuroleptic haloperidol.

Patients on atypical antipsychotic drugs: another high-risk group for type 2 diabetes

Patients with schizophrenia are more likely than the general population to develop diabetes, which contributes to a high risk of cardiovascular complications; individuals with schizophrenia are two to three times more likely to die from cardiovascular disease than the general population. The risk of diabetes, and hence cardiovascular disease, is particularly increased by some of the new atypical antipsychotic drugs. Individuals taking an atypical antipsychotic drug, particularly younger patients under 40 years of age (odds ratio 1.63, 95% CI 1.23-2.16), represent an underrecognized group at high risk of type 2 diabetes. The mechanisms responsible for antipsychotic-induced diabetes remain unclear. Hypotheses include these drugs' potential to cause weight gain, possibly through antagonism at the H(1), 5-HT(2A), or 5-HT(2C) receptors. Other mechanisms independent of weight gain lead to elevation of serum leptin and insulin resistance. Patients with psychoses have difficulties with diet and lifestyle interventions for diabetes and weight management. If hyperglycemia develops, withdrawal from antipsychotic medication will often be inappropriate, and a change to an atypical antipsychotic drug with lower diabetogenic potential should be considered, especially in younger patients. Management of psychoses should routinely include body weight and blood glucose monitoring and steps to promote exercise and minimize weight gain. Careful collaboration between the psychiatric and diabetology teams is essential to minimize the risk of diabetes in patients taking atypical antipsychotic medication and for effective management when it develops. This collaboration will also help minimize the already high risk of cardiovascular disease in individuals with schizophrenia.

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.

Metabolic Issues With Atypical Antipsychotics in Primary Care: Dispelling the Myths

BACKGROUND: Recently, much attention has been focused on the increased rate of metabolic syndrome componen ts among psychiatric patients, including glucose intolerance, hyperglycemia, diabetes mellitus, hyperlipidemia, hypertension, and weight gain. Various reports have identified cases of newly diagnosed diabetes during treatment with atypical antipsychotic agents. However, the question remains whether there is a relationship between atypical antipsychotic use and the metabolic syndrome or whether there is a higher risk in this population irrespective of medication use. METHOD: Many articles on antipsychotics and metabolic issues are reviews of case reports or small, cross-sectional laboratory studies highlighting the suspected potential for differing rates of new-onset diabetes cases. We conducted a retrospective review of the literature from 1998 through 2002, using the MEDLINE database, and recent studies presented at major psychiatric medical conferences to create a broader perspective on the metabolic issues. RESULTS: We identified over 70 abstracts and published manuscripts, including case reports; cross-sectional lab studies; retrospective analyses of head-to-head, controlled clinical studies; retrospective database studies; pharmacoepidemiology studies; and prospective head-to-head studies presented in the past 4 years. Studies assessed differences in fasting plasma glucose, oral glucose tolerance tests (OGTT), modified OGTT, frequently sampled intravenous glucose tolerance tests, homeostasis model assessment-insulin resistance, odds or hazard ratios, prevalence, and incidence, as well as other elements of the metabolic syndrome. CONCLUSION: Data from this large body of scientific evidence indicate that the psychiatric patient population may be at a higher risk for the development of obesity, glucose homeostasis dysregulation, and hyperlipidemia compared with the general population. The available data do not demonstrate a consistent or clinically significant difference in the risk of new-onset diabetes during treatment with the various atypical antipsychotic agents.

Metabolic consequences of atypical antipsychotic drugs

Atypical antipsychotic drugs have become the treatment of choice for psychotic disorders. However, these medications, though certainly superior in many respects to the more traditional medications, have been shown to have a number of untoward consequences. Understanding of the metabolic consequences of these medications is essential for the psychiatrist. The possible development of diabetes, weight gain, and hypertriglyceridemia in patients taking atypical antipsychotics makes it imperative that the prescribing physician regularly monitor patients on these agents. One possible monitoring scheme is outlined and recommendations for treatment are discussed.

Severe weight gain induced by combination treatment with risperidone and paroxetine

Successful combination therapy with atypical antipsychotics and selective serotonin reuptake inhibitors has been reported for several psychiatric conditions. However, great attention should be paid to the possible adverse effects. In this retrospective chart review, we focused on the drug-drug interaction of paroxetine and risperidone. Retrospectively, we identified two patients treated with a combination of risperidone and paroxetine therapy, and analyzed their medical records. During a 3-month period of monotherapy with risperidone, the changes in body weight were +/- 0.0 kg in Patient 1 and -2.0 kg in Patient 2. In contrast, during combination therapy with paroxetine and risperidone, the body-weight changes were +14.0 kg in Patient 1 (after 4 months) and +13.5 kg in Patient 2 (after 5 months). In addition, diabetes mellitus was observed in Patient 2. Regarding the mechanism of severe weight gain in these two patients, we speculate a drug-drug interaction involving inhibition of the cytochrome P450 enzyme 2D6 (CYP4502D6) by paroxetine.

Relapse and rehospitalisation rates in patients with schizophrenia: effects of second generation antipsychotics

Recent studies suggest that the risk of relapse in patients with schizophrenia is approximately 3.5% per month. Predictors of more frequent relapses include poor compliance with antipsychotic drug treatment, severe residual psychopathology, poor insight into the illness and the need for treatment, comorbid substance abuse, and poor relationships between patients, families and care providers. Although conventional antipsychotic drugs, such as haloperidol and fluphenazine, are effective in preventing relapse, second generation antipsychotic drugs, such as clozapine, risperidone and olanzapine, appear to be superior in preventing relapse and improving the patient's quality of life. The development of adverse events can undermine treatment response and relapse prevention. Minimising adverse effects thus helps to improve treatment compliance and prevent relapse. Second generation antipsychotic drugs tend to have fewer adverse effects than conventional agents, especially pseudoparkinsonism and akathisia. The societal costs of treating patients with schizophrenia can be lessened by employing strategies that decrease relapse and the need for rehospitalisation, the most costly treatment alternative.

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.