New-onset diabetes mellitus and diabetic ketoacidosis associated with olanzapine treatment

Pharmacological treatment of psychotic agitation

The presentation of agitated psychotic patients to psychiatric emergency services is a common occurrence. The traditionally accepted treatment for such patients involves the use of a typical antipsychotic, generally haloperidol. More recently benzodiazepines, such as lorazepam, have been used in combination with antipsychotics due to their sedative properties and relatively benign adverse effect profiles. Standard clinical protocol at many institutions involves the intramuscular administration of 5 to 10mg of haloperidol and 1 to 2mg of lorazepam. Atypical antipsychotics have gained acceptance as first-line treatments for psychotic disorders. These drugs are seen as an improvement over traditional antipsychotics because of their increased efficacy and reduced extrapyramidal effects. The utility of atypical antipsychotics in the emergency setting has been relatively unexplored because slow titration schedules or dose-limiting adverse effects for some members of the class have made this form of treatment impractical. However, the recent availability of oral liquid and rapidly dissolving tablet preparations of some atypical agents has provided useful alternatives in some cases. Nevertheless, for many patients a parenteral drug is the only desirable or feasible treatment option. Intramuscular preparations of the atypical antipsychotics olanzapine and ziprasidone have been developed, and are close to launch in the US. The availability of a rapid-acting intramuscular preparation of an atypical antipsychotic could represent a significant advancement in the treatment of agitation associated with psychosis.

Olanzapine associated weight gain, hyperglycemia and neuroleptic malignant syndrome: case report

We describe here a case of olanzapine associated weight gain, hyperglycemia and neuroleptic malignant syndrome in a 64 year-old woman with a significant medical history. Eighteen weeks after initiating olanzapine, Mrs X lost glycemic control, exhibited signs and symptoms consistent with neuroleptic malignant syndrome and gained 8.9 kg. We suggest that utilization of olanzapine in the less medically stable geriatric patient be implemented with vigilant monitoring for such complications mentioned above.

Diabetes mellitus and other metabolic disturbances induced by atypical antipsychotic agents

Atypical antipsychotic agents offer significant advantages over older conventional antipsychotic agents. The reduction in antipsychotic drug-associated extrapyramidal symptoms and the potential reduced risk for tardive dyskinesia, compared to conventional drugs, are major advances in the treatment of psychotic patients. However, recent reports of hyperglycemia, new-onset diabetes mellitus, diabetic ketoacidosis, weight gain, and lipid abnormalities associated with atypical antipsychotic agents have emerged. A review of the recent literature and an approach to the evaluation of risk factors to aide in the safe use of atypical antipsychotic agents in presented.

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.

Olanzapine-induced destabilization of diabetes in the absence of weight gain

OBJECTIVE

To provide evidence that olanzapine can cause glucose dysregulation by a mechanism other than weight gain.

METHOD

I report a case of a diabetic patient who developed glucose dysregulation soon after initiation of olanzapine treatment, occurring in the absence of weight gain. I compare this case to previous case reports.

RESULTS

Our patient developed persistent hyperglycaemia within 3 weeks of initiating treatment with olanzapine. Weight recorded just prior to commencement and soon after discontinuation of olanzapine were not significantly different.

CONCLUSION

Controlled studies are necessary to elucidate the mechanism by which olanzapine can cause dysregulation of glucose homeostasis, and to develop guidelines for the use of olanzapine in patients with known diabetes as well as in patients with risk factors for diabetes.

Bodyweight gain associated with atypical antipsychotics: epidemiology and therapeutic implications

Atypical antipsychotic medications are associated with different adverse effects and efficacy profiles compared with conventional antipsychotics (i.e. less extrapyramidal symptoms, improved-efficacy against negative symptoms and cognitive deficits, and most often a greater ability to improve patients' quality of life). However, the atypical antipsychotics may be associated with clinically significant bodyweight gain, increasing the risk of medical comorbidity, including diabetes mellitus, hypertension, cardiovascular disease and hyperlipidaemia. This literature review assesses the various bodyweight gain liabilities associated with atypical antipsychotics, as well as the effects of bodyweight gain on quality of life. The issue of prevention and management of this often neglected adverse effect is also examined. Most studies reviewed indicate that clozapine and olanzapine are associated with more bodyweight gain than the other atypical antipsychotics. There are potential factors that place certain patients at greater risk for bodyweight gain, including low pretreatment body mass index, young age and being of female gender. Furthermore, bodyweight gain associated with the use of atypical antipsychotics has been reported to be associated with clinical improvement, although this has not been substantiated widely. It is unclear whether increased medical comorbidity, including diabetes mellitus, coronary artery disease and/or elevated triglyceride levels, is secondary to the bodyweight gain associated with atypical antipsychotics, or the result of the agents themselves. A patient's quality of life may be greatly affected by excessive bodyweight gain; either by increased comorbid medical illness, an increased relapse rate associated with noncompliance, or the social stigma associated with being obese. However, most studies reveal that treatment with atypical antipsychotic medications is associated with improved quality of life compared with that achieved with conventional antipsychotic medications. Because bodyweight is an important health risk associated with atypical antipsychotics, prevention and effective management of bodyweight are paramount in preventing comorbid medical illness, relapse and possible noncompliance.

Ziprasidone: an atypical antipsychotic drug for the treatment of schizophrenia

BACKGROUND

Over the past decade, use of the atypical antipsychotic drugs clozapine, risperidone, olanzapine, and quetiapine has significantly changed the treatment of schizophrenia in the United States. The ability to make optimal drug choices will depend on determining whether there are clinically important differences between these drugs.

OBJECTIVE

This review describes ziprasidone, the most recently introduced antipsychotic drug. Its mechanism of action, pharmacokinetics, and adverse-effect profile are discussed, and the results of clinical efficacy trials are summarized.

METHODS

This review of ziprasidone is based on data from premarketing clinical efficacy and safety trials, a briefing document from the US Food and Drug Administration Psychopharmacological Drugs Advisory Committee, published studies, and abstracts presented at national and international meetings. International Pharmaceutical Abstracts and MEDLINE were searched for relevant citations, with no limitation on year.

RESULTS

Ziprasidone has been reported to be an effective antipsychotic drug for both positive and negative symptoms of schizophrenia, and long-term use has been effective in preventing relapse. Its 5-hydroxytryptamine (HT)1D-antagonist and 5-HT(1A)-agonist activity are consistent with a potential for antidepressant and anxiolytic activity beyond its antipsychotic effects. Ziprasidone has been associated with a low incidence of sedative effects, a low likelihood of extrapyramidal symptoms and postural hypotension, and no anticholinergic effect, although it may cause transient hyperprolactinemia. Unlike most atypical antipsychotic drugs, ziprasidone is not associated with weight gain, hyperlipidemia, or elevated plasma glucose levels. It is, however, more likely than other atypical antipsychotic drugs to increase the QTc interval (QT interval corrected for heart rate). For acute psychotic symptoms in patients with schizophrenia, schizoaffective disorder, or acute mania, ziprasidone is administered twice daily at a usual daily dose of 80 to 160 mg, whereas 40 mg/d may be an effective maintenance dose.

CONCLUSIONS

Differences in efficacy and tolerability between existing atypical antipsychotic drugs allow individualization of drug therapy for patients with schizophrenia or schizoaffective disorder. Ziprasidone differs from other atypical antipsychotic drugs in several clinically important ways, although further experience is necessary to clarify the significance of these differences.

Clozapine-associated diabetes

Clozapine is a potent antipsychotic agent that has been marketed since 1990. Several published reports of diabetes mellitus occurring with clozapine therapy have appeared during the past 5 years. Because the risk and characteristics of clozapine-associated diabetes mellitus remain unclear, we conducted a descriptive epidemiologic study of spontaneous adverse event reports of hyperglycemia occurring in clozapine-treated patients. The Food and Drug Administration MedWatch surveillance program was queried (January 1990 through February 2001), and the results were pooled with published cases. Parameters assessed included documentation of diabetes, clinical severity, new-onset diabetes versus exacerbation of preexisting disease, demographic characteristics of patients, time to onset of hyperglycemia, and effect of drug discontinuation and rechallenge. We identified 384 reports. Of these, new-onset diabetes was diagnosed definitively in 242 patients, and 54 patients had exacerbation of preexisting disease. The mean (+/- SD) age was 40 +/- 12 years (range, 13 to 77). The male:female ratio was 2:0. Most cases appeared within 6 months of initiating clozapine therapy. One patient developed diabetes following a single 500-mg dose. There were 80 cases of metabolic acidosis or ketosis. Twenty-five patients died during hyperglycemic episodes. Forty-six patients had improved glycemic control after discontinuation or dose reduction of the drug.A causal relationship between clozapine and diabetes is suggested by the number of reports, the temporal relation to clozapine initiation, the relatively young age of the affected patients, and the prompt reversibility on withdrawal of the drug in some patients. The severity of reported cases ranged from mild glucose intolerance to diabetic ketoacidosis or hyperosmolar coma.

Olanzapine-induced diabetic ketoacidosis

OBJECTIVE

To report the case of a patient taking olanzapine who developed diabetic ketoacidosis (DKA).

CASE SUMMARY

A 46-year-old African American woman with no previous history of diabetes mellitus was admitted to the hospital and subsequently diagnosed with DKA and acute pancreatitis. The patient had been taking olanzapine, valproic acid, carbamazepine, hydrochlorothiazide/triamterene, and conjugated estrogens prior to admission. Olanzapine was the last medication added to the regimen. In addition to clinicians treating the DKA with appropriate interventions, olanzapine (due to possible association with hyperglycemia and DKA) as well as valproic acid (due to possible association with pancreatitis) were discontinued from the medication regimen. The patient was discharged home and her most recent glycosylated hemoglobin and fasting glucose concentrations have been within the normal range.

DISCUSSION

Atypical antipsychotics, such as olanzapine, have been associated with hyperglycemia and possibly DKA. We believe that this occurred in our patient who had no previous history of diabetes mellitus. Possible mechanisms of action and potential confounding variables are discussed.

CONCLUSIONS

Clinicians should monitor blood glucose concentrations periodically in patients taking olanzapine, especially in those patients with risk factors for diabetes mellitus.

Dramatic worsening of type 2 diabetes mellitus due to olanzapine after 3 years of therapy

Olanzapine, a serotonin-dopamine-receptor antagonist, is an atypical antipsychotic agent used to treat schizophrenia and other psychotic disorders. It is preferred over older antipsychotics because of its relatively low frequency of sedation, orthostatic hypotension, extrapyramidal symptoms, and anticholinergic side effects. A 45-year-old man with well-controlled type 2 diabetes mellitus experienced an abrupt worsening of his diabetes after 3 years of olanzapine therapy His hemoglobin A1c (HbA1c) level rose from a baseline of 5.9-6.2% to 12.5%. Discontinuation of olanzapine by means of a 3-month taper resulted in a reduction in HbA1c to pretreatment levels. Although cases of olanzapine-induced hyperglycemia have been documented in the literature, this complication has not been reported in a patient maintained on therapy for this duration. Clinicians should be aware of this possible complication in patients receiving long-term olanzapine therapy.

A Perspective on the Primary Care of Patients With Behavior, Mood, and Thought Disturbances: Clinical Applications of Olanzapine

Primary care practitioners are in an ideal position to initiate treatment for patients with behavior, mood, and thought disturbances. It is believed that early identification and treatment of these symptomatic features of primary or secondary central nervous system disorders may significantly reduce morbidity and benefit the patient, his/her family, and involved caregivers, including the primary care physician. A broad list of central nervous system-active medications are utilized by family physicians to treat patients who exhibit symptoms of agitation, altered mood, and disordered thought. Some medications have demonstrated superiority over placebo or active medicines in reported clinical trials. This article is a brief overview of the safety and efficacy from reported studies of the use of medications frequently used to treat symptoms related to behavior, mood, and thought disturbances, with a specific focus on the clinical applicability of olanzapine.

Antipsychotic medication: effects on regulation of glucose and lipids

Since the introduction of chlorpromazine in the 1950s, antipsychotics have been used for the treatment of schizophrenia. The phenothiazines were followed by the butyrophenones, particularly haloperidol. With all the movement disorder side effects of these medications (extrapyramidal syndrome, akathisia, tardive dyskinesia), the pharmaceutical industry has gradually released atypical antipsychotics. This class includes clozapine (released in the USA in 1990), risperidone (1994), olanzapine (1996), quetiapine (1998) and ziprasidone (2001). However, the rate of diabetes mellitus in patients with schizophrenia appeared to increase with the availability of this class of medications. In reviewing rate and degree of changes in weight, glucose control and lipid levels induced by typical and atypical antipsychotics, it was found that in contrast to case reports, there is a dearth of retrospective, open and controlled studies. However, in studies as early as 1964, significant weight increases were found to be associated with use of chlorpromazine. While the phenothiazines may have some effect on patients with chemical diabetes, there is little evidence of the typical antipsychotics producing diabetes mellitus de novo, or worsening diabetes that is already been discovered. Ziprasidone appears to be the antipsychotic with the most beneficial combination of effects: no weight gain, no change in glucose utilisation and reductions in cholesterol and serum triglycerides (TGs).

Diabetic ketoacidosis associated with olanzapine in an adolescent patient

Olanzapine (Zyprexa) is an atypical neuroleptic used in adult and pediatric patients for the management of schizophrenia. Common side effects include increased appetite and weight gain. An uncommon but severe adverse effect is the development of diabetic ketoacidosis, reported until now only in adults. We report a case of acute onset diabetic ketoacidosis presenting in a 16-year-old girl during olanzapine therapy.

The interface of psychiatric disorders and diabetes mellitus

This paper reviews recent developments at the interface between psychiatric disorders and diabetes mellitus. A Medline search for the interval 1994 to 2000 was conducted, and the review addresses selected content from the search involving the following: 1) neuroleptic induced diabetes and the associated issue of diabetes and schizophrenia; 2) developments concerning various facets of the relationship of diabetes mellitus and depressive disorder; and 3) recent findings with regard to specific diabetic complications and their links to psychiatry.

Atypical antipsychotics: new directions and new challenges in the treatment of schizophrenia

"Atypical" antipsychotics represent a new generation of antipsychotics with a significantly lower incidence of extrapyramidal side effects (EPS), as well as little or no effect on prolactin elevation. These advantages constitute a major improvement in the treatment of patients with schizophrenia. The exact mechanisms that make these drugs atypical is not clear. However, a preferential action on serotonin 5-HT2 or D4 receptors, or a more rapid dissociation from the dopamine D2 receptor, may account for atypicality. Although the atypical antipsychotics have overcome EPS, other side effects such as weight gain and impaired glucose tolerance/lipid abnormalities have come to the fore. Thus, the challenges are far from over. The current atypicals are much more effective against the psychosis of schizophrenia than against the other, more enduring aspects of this disorder, e.g. negative symptoms and cognitive dysfunction. At present, the atypicals use a "pharmacological shotgun" strategy to treat aspects of the disease in all patients. A more sophisticated and perhaps effective approach to schizophrenia may lie in independently targeting the pathophysiological mechanisms of each clinical dimension (i.e. positive, negative, cognitive, and affective) with more selective drugs that can be combined and individually titrated to the needs of each patient.

Olanzapine-induced diabetes mellitus

OBJECTIVE

To report two cases of new-onset diabetes mellitus resulting after the initiation of olanzapine treatment.

CASE SUMMARY

A 31-year-old African American man and a 44-year-old white man, both with schizoaffective disorder, developed diabetes mellitus within weeks or months of olanzapine initiation.

DISCUSSION

Our reports of new-onset diabetes due to olanzapine are consistent with those in the literature. Although the mechanism is not yet known, it has been hypothesized that perhaps damage to the pancreatic islet cells, weight gain, dysregulation of the sympathetic system, and insulin resistance are contributing factors.

CONCLUSIONS

Diabetes mellitus secondary to olanzapine use seems to be a rare occurrence. However, certain risk factors such as obesity, family history, and concomitant medications may predispose an individual to development of diabetes mellitus while taking olanzapine. An increased awareness of this reaction is essential in the treatment of patients at risk. Periodic serum glucose monitoring in these individuals may be warranted.

Antipsychotic metabolic effects: weight gain, diabetes mellitus, and lipid abnormalities

OBJECTIVE

To review published and nonpublished literature describing changes in weight, glucose homeostasis, and lipid milieu with antipsychotics.

METHODS

A Medline search was completed using the words weight gain, diabetes mellitus, cholesterol, triglycerides, risperidone, clozapine, olanzapine, quetiapine, ziprasidone, predictors, prolactin, obesity, and conventional antipsychotics. Publications, including original articles, review articles, letters to the editor, abstracts or posters presented at professional meetings in the last 4 years, and references from published articles, were collected. Manufacturers, including Eli Lilly Canada Inc, JanssenOrtho Inc, Pfizer Canada Inc, AstraZeneca Inc, and Novartis Pharmaceuticals, were contacted to retrieve additional medical information.

RESULTS

The topic of antipsychotic-induced weight gain is understudied, and there are relatively few well-controlled studies. Weight gain as a side effect has been described with both conventional and atypical antipsychotics. Moreover, some atypical antipsychotics are associated with de novo diabetes mellitus and increased serum triglyceride levels. Predictors of weight gain may be age, baseline body mass index, appetite stimulation, previous antipsychotic exposure, and antipsychotic treatment duration.

CONCLUSION

Significant weight gain is reported with the existing atypical antipsychotics. The weight gain described is highly distressing to patients, may reduce treatment adherence, and may increase the relative risk for diabetes mellitus and hypertriglyceridemia. Physicians employing these agents should routinely monitor weight, fasting blood glucose, and lipid profiles.

Atypical Antipsychotics and Glucose Dysregulation: A Series of 4 Cases

There have been reports in the psychiatric literature of the association of glucose dysregulation and diabetes mellitus with the use of atypical and typical (conventional) antipsychotics. We present a series of 4 additional cases in which psychotic disorders (DSM-IV) were treated with atypical antipsychotics, and patients subsequently developed glucose dysregulation or diabetes mellitus. The implications of these findings are discussed.

Olanzapine-lnduced hyperglycemic nonketonic coma

OBJECTIVE

To report a case of olanzapine-induced hyperglycemia leading to a hyperosmolar, hyperglycemic, nonketonic coma.

CASE SUMMARY

A 51-year-old, 85.5-kg (ideal body weight 79.9 kg), white man presented to a Veterans Affairs hospital with a serum glucose concentration of 1596 mg/dL. Soon thereafter, he went into a hyperosmolar, hyperglycemic, nonketonic coma. Olanzapine therapy had been instituted less than six months prior to this event; approximately two months before this event, his blood glucose was 108 mg/dL. Eight days after stopping olanzapine, the glucose concentration returned to normal, and the patient no longer required insulin nor any other glucose-lowering agents.

DISCUSSION

The insulin resistance caused by olanzapine is normally attributed to the weight gain associated with the drug. In this patient, it appears that olanzapine caused hyperglycemia by a mechanism other than weight gain.

CONCLUSIONS

This case report and others from the literature suggest that olanzapine therapy may induce hyperglycemia in some patients.

Atypical antipsychotics and hyperglycaemia

Hyperglycaemia is known occasionally to occur with conventional neuroleptics, but has more recently been associated with atypical antipsychotics especially clozapine and olanzapine. This article examines more closely this association. A review of relevant published literature from 1970 to date was undertaken following Medline and Embase searches in June 2000. Hyperglycaemia with clozapine was widely reported: spontaneous reports of either hyperglycaemia or ketoacidosis were described in a total of 17 people. In a five-year naturalistic study, 30.5% of patients taking clozapine were eventually diagnosed with Type 2 diabetes. With olanzapine, a total of 10 cases of hyperglycaemia and 5 cases of ketoacidosis have been published. Reports of hyperglycaemia with other atypicals are relatively scarce. The association of hyperglycaemia or ketoacidosis with clozapine and olanzapine appears to be a true drug-induced effect. Risk factors may include male gender, age of around 40 years and being non-Caucasian. The management of hyperglycaemia depends on the causative agent. With clozapine, treatment with oral hypoglycaemics has been successful. With olanzapine, other atypical antipsychotics may be considered. Blood glucose monitoring is essential for all patients starting clozapine or olanzapine.

New onset diabetes and atypical antipsychotics

As a class, the atypical antipsychotics are the first line treatment choice for the psychopharmacologic management of psychotic disorders. Emerging evidence currently suggests that at least two of the atypical antipsychotics, clozapine and olanzapine, and possibly quetiapine may be associated with the risk of new onset diabetes or serum glucose dyscontrol. Computerized Medline and Current Contents searches from years 1966 through June 2000 were undertaken to retrieve all pertinent studies and case reports of typical and atypical antipsychotics and glucose-insulin problems. Historically, both schizophrenia and the older antipsychotics medications have been reported to be associated with a similar risk for causing disruptions in serum glucose control. Additionally, diabetes has well recognized associations with a number of medical disorders such as cardiovascular disease; it is therefore worthy of attention. Hypothesized mechanisms for antipsychotic induced diabetes ranges from the antagonism of several neurotransmitter receptors to insulin resistance. A total of thirty-five cases of induced or exacerbated diabetes are presently available in the published literature; the vast majority of cases implicate clozapine (n=20) and olanzapine (n=15). In multiple cases, diabetic ketoacidosis has been the presenting symptom; daily atypical antipsychotic doses have been within acceptable ranges and were not considered to be excessive.

Atypical Antipsychotic Use in the Treatment of Psychosis in Primary Care

Atypical antipsychotics are a class of novel agents increasingly employed for the treatment of psychotic disorders. The pharmacodynamic properties of the atypicals appear to impact a broader spectrum of psychotic symptoms than had been appreciated with older generation antipsychotics. In addition, the atypical agents appear to have a reduced risk of neurologic side effects compared with conventional antipsychotic use. Both of these features enhance the appeal of the atypical antipsychotics and may be associated with enhanced patient compliance. The atypical antipsychotics appear to be effective for schizophrenia as well as other psychotic disorders, including schizoaffective disorder and mood disorders with psychotic features. Consequently, atypical antipsychotics are now considered to be the first-line treatment for schizophrenia, with the exception of clozapine, which is considered a second-line agent because of risks associated with its use. This review will discuss the literature on atypical antipsychotic efficacy in psychotic disorders. Issues related to antipsychotic use, dosing, adverse effects, and drug interactions are also discussed.

Clinical research on antipsychotics in bipolar disorder

Antipsychotics are commonly used in bipolar disorder, both for acute mania and in maintenance treatment. The authors review available clinical research concerning the use of both conventional and atypical antipsychotics in bipolar disorder and present recommendations for a number of key clinical situations based on this review. They also consider a number of important related questions, including whether there is evidence for an increased risk of tardive dyskinesia (TD) in patients with bipolar disorder, the potential role for antipsychotics in the treatment of bipolar depression, the role of antipsychotics in maintenance treatment of bipolar disorder, the potential for antipsychotics to induce depression in bipolar illness, and whether antipsychotics can be considered mood stabilizers with a place as monotherapy for bipolar mania. They conclude that standard treatment for acute mania should begin with a mood stabilizer, with benzodiazepines used as an adjunct for mild agitation or insomnia and antipsychotics used as an adjunct for highly agitated, psychotic, or severely manic patients. They also conclude that atypical antipsychotics are preferable to conventional antispychotics because of their more favorable side effect profile and reduced risk of tardive dyskinesia. They review the evidence for using atypical antipsychotics as first-line monotherapy for mania and conclude that more evidence concerning the risk of TD and their efficacy as maintenance treatment in bipolar disorder is needed before a conclusion can be made. Should the eventual risk of TD associated with atypical antipsychotics be found to be minimal and their efficacy in maintenance treatment found to be high, they could eventually be considered first line monotherapy for bipolar disorder. They conclude that treatment with an antipsychotic during bipolar depression should be limited to those patients who have psychosis and that atypical antipsychotics are preferred over conventional antipsychotics in this situation, not only because of their reduced risk of side effects but also because theoretically they may have antidepressant efficacy due to their effects on the serotonin system. The clinical research findings summarized in the article are, for the most part, supported by a recently published guideline based on a consensus of clinical experts.

Elevated sorbitol concentration in the cerebrospinal fluid of patients with mood disorders

This study was undertaken to test the hypothesis that a specific pathophysiological mechanism of diabetic neuropathy, namely increased polyol pathway flux, could be operative in patients with bipolar and unipolar mood disorders. Numerous studies have shown abnormalities of carbohydrate metabolism, including high rates of diabetes mellitus, in patients with mood disorders. Several studies have found that peripheral neuropathy is a risk factor for depression in diabetics. Furthermore, increased polyol pathway flux results in elevated sorbitol concentrations in peripheral tissues and cerebrospinal fluid (CSF) of diabetics with neuropathy. The purpose of this study was to determine whether sorbitol concentration is elevated in the CSF of non-medically ill patients with mood disorders. Lumbar punctures were performed on 30 subjects - 10 with bipolar mood disorder, 10 with unipolar mood disorder, and 10 age-matched normal controls, and CSF sorbitol concentrations were measured, using a gas chromatographic-mass spectroscopic technique. The mean+/-standard deviation of CSF sorbitol concentrations differed among the three groups as follows: bipolar (22.9+/-4.6 micromoles/l) > unipolar (19.0+/-2.8 micromoles/l)>normal control (15. 6+/-1.9 micromoles/l). One-way ANOVA showed significant (P=0.0002) differences among the three groups. Post-hoc tests indicated a significant (P<0.05) difference between bipolars and normal controls, bipolars and unipolars, and unipolars and normal controls. Further investigation is needed to determine the pathophysiological significance of this novel finding of elevated sorbitol concentration in the CSF of patients with mood disorders.

Olanzapine-induced glucose dysregulation

OBJECTIVE

To report a patient who developed severe exacerbation of type 2 diabetes mellitus after the initiation of olanzapine therapy.

CASE SUMMARY

A 54-year-old African-American woman developed severe glucose dysregulation 12 days after the initiation of olanzapine. Prior to starting olanzapine therapy, the patient's diabetes was controlled by diet modification with a glycosylated hemoglobin of 6.5%. During olanzapine therapy, blood glucose concentrations could not be regulated despite use of antidiabetic agents, insulin, and dietary interventions. The patient also gained a total of 13 kg. Two weeks after discontinuation of all antipsychotic medications (olanzapine, quetiapine), the patient's blood glucose concentrations became better regulated and remained better controlled until discharge.

DISCUSSION

All atypical antipsychotics are associated with weight gain. Obesity is a well-documented risk factor for developing type 2 diabetes mellitus. Currently there are only six published reports that implicate olanzapine as being associated with glucose dysregulation. The exact cause of glucose dysregulation with olanzapine is unclear, but weight gain does not seem to be the sole etiology. It has been hypothesized that serotonin (5-HT1A) antagonism may decrease the responsiveness of the pancreatic beta-cells. This would then result in inappropriately low insulin secretion and, therefore, hyperglycemia. Based on the Naranjo probability scale, the likelihood that olanzapine caused the glucose dysregulation in our patient was possible.

CONCLUSIONS

Although olanzapine has shown greater clinical efficacy and is associated with fewer extrapyramidal side effects than typical antipsychotics, it may produce exacerbation or new emergence of diabetes mellitus. Further examination of the incidence and etiology of glucose dysregulation after the initiation of olanzapine therapy is necessary.

Weight gain associated with psychotropic drugs

Weight gain is a common adverse effect of psychotropic drugs. Clinically significant weight gain puts the patient at risk for coronary heart disease, hypertension, Type II diabetes, dyslipidaemia and cancer, and can lead to non-compliance, with the probability of relapse and subsequent (re)hospitalization. This review focuses on specific drug classes such as antipsychotics, antidepressants, mood stabilizers and anxiolytics that have a propensity to induce clinically significant weight gain. Patients should be informed of potential drug-induced weight gain and instructed in the importance of weight management techniques (e.g., proper nutrition, physical exercise, behaviour modification). Individual patient-risk profiles should also be assessed. To ensure adherence to treatment, a proactive physician-patient relationship is essential. Patient compliance and quality-of-life issues are addressed. For appropriate medication selection, the clinician should consider the weight gain potential of various psychotropic agents.