Effects of olanzapine and haloperidol on the metabolic status of healthy men

Insulin effects on core neurotransmitter pathways involved in schizophrenia neurobiology: a meta-analysis of preclinical studies. Implications for the treatment

Impairment of insulin action and metabolic dysregulation have traditionally been associated with schizophrenia, although the molecular basis of such association remains still elusive. The present meta-analysis aims to assess the impact of insulin action manipulations (i.e., hyperinsulinemia, hypoinsulinemia, systemic or brain insulin resistance) on glutamatergic, dopaminergic, γ-aminobutyric acid (GABA)ergic, and serotonergic pathways in the central nervous system. More than one hundred outcomes, including transcript or protein levels, kinetic parameters, and other components of the neurotransmitter pathways, were collected from cultured cells, animals, or humans, and meta-analyzed by applying a random-effects model and adopting Hedges'g to compare means. Two hundred fifteen studies met the inclusion criteria, of which 180 entered the quantitative synthesis. Significant impairments in key regulators of synaptic plasticity processes were detected as the result of insulin handlings. Specifically, protein levels of N-methyl-D-aspartate receptor (NMDAR) subunits including type 2A (NR2A) (Hedges' g = -0.95, 95%C.I. = -1.50, -0.39; p = 0.001; I2 = 47.46%) and 2B (NR2B) (Hedges'g = -0.69, 95%C.I. = -1.35, -0.02; p = 0.043; I2 = 62.09%), and Postsynaptic density protein 95 (PSD-95) (Hedges'g = -0.91, 95%C.I. = -1.51, -0.32; p = 0.003; I2 = 77.81%) were found reduced in insulin-resistant animal models. Moreover, insulin-resistant animals showed significantly impaired dopamine transporter activity, whereas the dopamine D2 receptor mRNA expression (Hedges'g = 3.259; 95%C.I. = 0.497, 6.020; p = 0.021; I2 = 90.61%) increased under insulin deficiency conditions. Insulin action modulated glutamate and GABA release, as well as several enzymes involved in GABA and serotonin synthesis. These results suggest that brain neurotransmitter systems are susceptible to insulin signaling abnormalities, resembling the discrete psychotic disorders' neurobiology and possibly contributing to the development of neurobiological hallmarks of treatment-resistant schizophrenia.

The anxiolytic drug opipramol inhibits insulin-induced lipogenesis in fat cells and insulin secretion in pancreatic islets

The antidepressant drug opipramol has been reported to exert antilipolytic effect in human adipocytes, suggesting that alongside its neuropharmacological properties, this agent might modulate lipid utilization by peripheral tissues. However, patients treated for depression or anxiety disorders by this tricyclic compound do not exhibit the body weight gain or the glucose tolerance alterations observed with various other antidepressant or antipsychotic agents such as amitriptyline and olanzapine, respectively. To examine whether opipramol reproduces or impairs other actions of insulin, its direct effects on glucose transport, lipogenesis and lipolysis were investigated in adipocytes while its influence on insulin secretion was studied in pancreatic islets. In mouse and rat adipocytes, opipramol did not activate triglyceride breakdown, but partially inhibited the lipolytic action of isoprenaline or forskolin, especially in the 10-100 μM range. At 100 μM, opipramol also inhibited the glucose incorporation into lipids without limiting the glucose transport in mouse adipocytes. In pancreatic islets, opipramol acutely impaired the stimulation of insulin secretion by various activators (high glucose, high potassium, forskolin...). Similar inhibitory effects were observed in mouse and rat pancreatic islets and were reproduced with 100 μM haloperidol, in a manner that was independent from alpha2-adrenoceptor activation but sensitive to Ca²⁺ release. All these results indicated that the anxiolytic drug opipramol is not only active in central nervous system but also in multiple peripheral tissues and endocrine organs. Due to its capacity to modulate the lipid and carbohydrate metabolisms, opipramol deserves further studies in order to explore its therapeutic potential for the treatment of obese and diabetic states.

Insulin and glucose metabolism with olanzapine and a combination of olanzapine and samidorphan: exploratory phase 1 results in healthy volunteers

A combination of olanzapine and samidorphan (OLZ/SAM) received US Food and Drug Administration approval in May 2021 for the treatment of adults with schizophrenia or bipolar I disorder. OLZ/SAM provides the efficacy of olanzapine, while mitigating olanzapine-associated weight gain. This exploratory study characterized the metabolic profile of OLZ/SAM in healthy volunteers to gain mechanistic insights. Volunteers received once-daily oral 10 mg/10 mg OLZ/SAM, 10 mg olanzapine, or placebo for 21 days. Assessments included insulin sensitivity during an oral glucose tolerance test (OGTT), hyperinsulinemic-euglycemic clamp, other measures of glucose/lipid metabolism, and adverse event (AE) monitoring. Treatment effects were estimated with analysis of covariance. In total, 60 subjects were randomized (double-blind; placebo, n = 12; olanzapine, n = 24; OLZ/SAM, n = 24). Olanzapine resulted in hyperinsulinemia and reduced insulin sensitivity during an OGTT at day 19, changes not observed with OLZ/SAM or placebo. Insulin sensitivity, measured by hyperinsulinemic-euglycemic clamp, was decreased in all treatment groups relative to baseline, but this effect was greatest with olanzapine and OLZ/SAM. Although postprandial (OGTT) glucose and fasting cholesterol concentrations were similarly increased with olanzapine or OLZ/SAM, other early metabolic effects were distinct, including post-OGTT C-peptide concentrations and aspects of energy metabolism. Forty-nine subjects (81.7%) experienced at least 1 AE, most mild or moderate in severity. OLZ/SAM appeared to mitigate some of olanzapine's unfavorable postprandial metabolic effects (e.g., hyperinsulinemia, elevated C-peptide) in this exploratory study. These findings supplement the body of evidence from completed or ongoing OLZ/SAM clinical trials supporting its role in the treatment of schizophrenia and bipolar I disorder.

Metabolic disturbances associated with antipsychotic drug treatment in patients with schizophrenia: State-of-the-art and future perspectives

Metabolic disturbances and obesity are major cardiovascular risk factors in patients with schizophrenia, resulting in a higher mortality rate and shorter life expectancy compared with those in the general population. Although schizophrenia and metabolic disturbances may share certain genetic or pathobiological risks, antipsychotics, particularly those of second generation, may further increase the risk of weight gain and metabolic disturbances in patients with schizophrenia. This review included articles on weight gain and metabolic disturbances related to antipsychotics and their mechanisms, monitoring guidelines, and interventions. Nearly all antipsychotics are associated with weight gain, but the degree of the weight gain varies considerably. Although certain neurotransmitter receptor-binding affinities and hormones are correlated with weight gain and specific metabolic abnormalities, the precise mechanisms underlying antipsychotic-induced weight gain and metabolic disturbances remain unclear. Emerging evidence indicates the role of genetic polymorphisms associated with antipsychotic-induced weight gain and antipsychotic-induced metabolic disturbances. Although many guidelines for screening and monitoring antipsychotic-induced metabolic disturbances have been developed, they are not routinely implemented in clinical care. Numerous studies have also investigated strategies for managing antipsychotic-induced metabolic disturbances. Thus, patients and their caregivers must be educated and motivated to pursue a healthier life through smoking cessation and dietary and physical activity programs. If lifestyle intervention fails, switching to another antipsychotic drug with a lower metabolic risk or adding adjunctive medication to mitigate weight gain should be considered. Antipsychotic medications are essential for schizophrenia treatment, hence clinicians should monitor and manage the resulting weight gain and metabolic disturbances.

Peripheral metabolic state and immune system in first-episode psychosis - A gene expression study with a prospective one-year follow-up

he excess availability of glucose and lipids can also have an impact on the dynamics of activation and regulation of peripheral immune cellsWe aimed at understanding the correlations between peripheral metabolic state and immune system during the first year in first-episode psychosis (FEP). Patients with FEP (n = 67) and matched controls (n = 38), aged 18-40 years, were met at baseline, 2 and 12 months. Fasting peripheral blood samples were collected. We applied the NanoString nCounter in-solution hybridization technology to determine gene expression levels of 178 candidate genes reflecting activation of the immune system. Serum triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL) cholesterol and insulin and plasma glucose (fP-Gluc) were measured. We applied Ingenuity Pathway Analysis (IPA) to visualize enrichment of genes to functional classes. Strength of positive or negative regulation of the disease and functional pathways was deduced from IPA activation Z-score at the three evaluation points. We correlated gene expression with plasma glucose, triglycerids and HDL and LDL, and used hierarchical clustering of the pairwise correlations to identify groups of genes with similar correlation patterns with metabolic markers. In patients, initially, genes associated with the innate immune system response pathways were upregulated, which decreased by 12 months. Furthermore, genes associated with apoptosis and T cell death were downregulated, and genes associated with lipid metabolism were increasingly downregulated by 12 months. The immune activation was thus an acute phase during illness onset. At baseline, after controlling for multiple testing, 31/178 genes correlated positively with fasting glucose levels, and 54/178 genes negatively with triglycerides in patients only. The gene clusters showed patterns of correlations with metabolic markers over time. The results suggest a functional link between peripheral immune system and metabolic state in FEP. Metabolic factors may have had an influence on the initial activation of the innate immune system. Future work is necessary to understand the role of metabolic state in the regulation of immune response in the early phases of psychosis.

A comparison of the metabolic side-effects of the second-generation antipsychotic drugs risperidone and paliperidone in animal models

BACKGROUND

The second generation antipsychotic drugs represent the most common form of pharmacotherapy for schizophrenia disorders. It is now well established that most of the second generation drugs cause metabolic side-effects. Risperidone and its active metabolite paliperidone (9-hydroxyrisperidone) are two commonly used antipsychotic drugs with moderate metabolic liability. However, there is a dearth of preclinical data that directly compares the metabolic effects of these two drugs, using sophisticated experimental procedures. The goal of the present study was to compare metabolic effects for each drug versus control animals.

METHODS

Adult female rats were acutely treated with either risperidone (0.1, 0.5, 1, 2, 6 mg/kg), paliperidone (0.1, 0.5, 1, 2, 6 mg/kg) or vehicle and subjected to the glucose tolerance test; plasma was collected to measure insulin levels to measure insulin resistance with HOMA-IR. Separate groups of rats were treated with either risperidone (1, 6 mg/kg), paliperidone (1, 6 mg/kg) or vehicle, and subjected to the hyperinsulinemic euglycemic clamp.

RESULTS

Fasting glucose levels were increased by all but the lowest dose of risperidone, but only with the highest dose of paliperidone. HOMA-IR increased for both drugs with all but the lowest dose, while the three highest doses decreased glucose tolerance for both drugs. Risperidone and paliperidone both exhibited dose-dependent decreases in the glucose infusion rate in the clamp, reflecting pronounced insulin resistance.

CONCLUSIONS

In preclinical models, both risperidone and paliperidone exhibited notable metabolic side-effects that were dose-dependent. Differences between the two were modest, and most notable as effects on fasting glucose.

Peripheral mechanisms of acute olanzapine induced metabolic dysfunction: A review of in vivo models and treatment approaches

Antipsychotic (AP) medications are associated with an increased risk for developing metabolic side effects including weight gain, dyslipidemia, hypertension, type 2 diabetes (T2D), and cardiovascular disease. Previous reviews have focused on the chronic metabolic side effects associated with AP use. However, an underappreciated aspect of APs are the rapid perturbations in glucose and lipid metabolism that occur with each dose of drug. The purpose of this narrative review is to summarize work examining the peripheral mechanisms of acute olanzapine-induced related metabolic disturbances. We also discuss recent studies that have attempted to elucidate treatment approaches to mitigate AP-induced impairments in fuel metabolism.

Effects of Olanzapine Combined With Samidorphan on Weight Gain in Schizophrenia: A 24-Week Phase 3 Study

OBJECTIVE

A combination of olanzapine and the opioid receptor antagonist samidorphan is under development for the treatment of schizophrenia and bipolar I disorder. The single-tablet combination treatment is intended to provide the efficacy of olanzapine while mitigating olanzapine-associated weight gain. In this phase 3 double-blind trial, the authors evaluated the weight profile of combined olanzapine/samidorphan compared with olanzapine in patients with schizophrenia.

METHODS

Adults (ages 18‒55 years) with schizophrenia were randomly assigned to receive either combination treatment with olanzapine and samidorphan or olanzapine treatment for 24 weeks. Primary endpoints were percent change from baseline in body weight and proportion of patients with ≥10% weight gain at week 24. The key secondary endpoint was the proportion of patients with ≥7% weight gain. Waist circumference and fasting metabolic laboratory parameters were also measured.

RESULTS

Of 561 patients who underwent randomization (olanzapine/samidorphan combination, N=280; olanzapine, N=281), 538 had at least one postbaseline weight assessment. At week 24, the least squares mean percent weight change from baseline was 4.21% (SE=0.68) in the olanzapine/samidorphan group and 6.59% (SE=0.67) in the olanzapine group (the difference of -2.38% [SE=0.76] was significant). Significantly fewer patients in the olanzapine/samidorphan combination group compared with the olanzapine group had weight gain ≥10% (17.8% and 29.8%, respectively; number needed to treat [NNT]=7.29; odds ratio=0.50) and weight gain ≥7% (27.5% and 42.7%, respectively; NNT=6.29; odds ratio=0.50). Increases in waist circumference were smaller in the olanzapine/samidorphan combination group compared with the olanzapine group. Schizophrenia symptom improvement was similar between treatment groups. Adverse events (in ≥10% of the groups) in the olanzapine/samidorphan and olanzapine groups included weight gain (24.8% and 36.2%), somnolence (21.2% and 18.1%), dry mouth (12.8% and 8.0%), and increased appetite (10.9% and 12.3%). Metabolic changes were small and similar between treatments.

CONCLUSIONS

Olanzapine/samidorphan combination treatment was associated with significantly less weight gain and smaller increases in waist circumference than olanzapine and was well tolerated. The antipsychotic efficacy of the combination treatment was similar to that of olanzapine monotherapy.

Nutrition problems in a severe burn patient with schizophrenia: a case report

Hypermetabolic conditions with nutrition deficiencies are common in patients with extensive burns. Balanced nutrition status is required to achieve adequate wound healing. Mental disorder, which tended to make a patient uncooperative, complicates the management. We report the case of a 35-year-old man with schizophrenia who suffered full- and partial-thickness burns in approximately 38% of total body surface area due to attempted suicide. The patient was hospitalized for 66 days and underwent multiple surgeries. His body mass index (BMI) was continuously low. Tissue injuries provoked inflammatory responses that contributed to metabolic disarrangement, meanwhile the presence of psychiatric disorder complicated the means of nutrition assessment and therapy needed to compensate for the high nutrition demand during the treatment period. Nutrition support should be assessed and adjusted continuously.

Assessment of lipid response to acute olanzapine administration in healthy adults

BACKGROUND

Atypical antipsychotics (AAP) can induce hypertriglyceridaemia and type 2 diabetes. Weight gain contributes to these effects, but there is evidence that AAP can have acute metabolic effects on glycaemia independent of weight change.

AIMS

We undertook a single-blind crossover study in eight healthy volunteers to assess whether the AAP olanzapine acutely increases triglyceride and free fatty acid in response to a high-fat oral load (50 g fat with no carbohydrate) and whether these effects are attenuated by the dopamine D2 receptor agonist bromocriptine.

METHODS

Participants underwent three treatments in random order: Olanzapine 10 mg plus placebo (OL + PL), Olanzapine 10 mg plus bromocriptine 5 mg (OL + BR) and placebo plus placebo (PL + PL).

RESULTS

Olanzapine increased plasma prolactin, an effect that was reversed by co-administration of the D2 receptor agonist bromocriptine (P = .0002). There were no significant differences in postprandial triglyceride (P = .8), free fatty acid (P = .4) or glucose (P = .8).

CONCLUSION

These results suggest that AAPs likely do not directly increase postprandial lipids but may do so indirectly via changes in body weight and/or glycaemia.

Effects of second-generation antipsychotics on human subcutaneous adipose tissue metabolism

OBJECTIVE

Metabolic syndrome is prevalent in up to 50% of schizophrenia patients, which reduces their quality of life and their compliance with the treatment. It is unclear whether metabolic adverse effects of these agents are due to their direct effect on insulin-sensitive tissues or are secondary to increased adiposity. The study aimed to investigate the direct effects of the second-generation antipsychotics olanzapine and aripiprazole on human subcutaneous adipose tissue and isolated adipocyte metabolism.

METHODS

Abdominal subcutaneous adipose tissue needle biopsies were taken from 72 healthy subjects (49 F/23 M; age: 19-78 yr; BMI: 20.0-35.6 kg/m²). Isolated adipocytes or adipose tissue were respectively pre-incubated short- (30 min) and long-term (24 h, 72 h) with or without olanzapine (0.004 μM - 20 μM) and aripiprazole (0.002 μM - 100 μM). Pre-incubated adipose tissue was then snap-frozen for mRNA expression analysis of adipokines genes and genes involved in inflammation, adipogenesis, and mitochondrial function. Isolated adipocytes were used to measure basal and insulin-stimulated glucose uptake and lipolysis.

RESULTS

Acute treatment with a therapeutic concentration of olanzapine decreases basal lipolysis in isolated adipocytes; this effect was not observed after long-term incubation with the drug. Supra-therapeutic concentration of aripiprazole reduced basal and insulin-stimulated glucose uptake after short- and long-term pre-incubation. Both drugs at supra-therapeutic concentrations downregulated the expression of the pro-inflammatory cytokines IL6 and IL1B genes after 72 h incubation. Similarly, supra-therapeutic concentrations of both drugs and therapeutic concentration of olanzapine, reduced the expression of PPARGC1A, PDK4, and CPT1B genes involved in the regulation of mitochondrial functions. Neither of the antipsychotics affected the expression of the main adipokines LEP and ADIPOQ, genes involved in the regulation of lipid metabolism, LPL and FASN, nor the master adipogenesis regulator, PPARG.

CONCLUSION

Therapheutic concentrations of olanzapine and aripiprazole have a moderate direct effect on adipocyte lipid and glucose metabolism, respectively. At supra-therapeutic concentrations, both of the antipsychotics seem to act as anti-inflammatory agents and mildly suppressed genes involved in the regulation of mitochondrial functions, which could potentially contribute to metabolic adverse effects. Alternatively, second-generation antipsychotics could induce metabolic side effects via acting on other insulin-sensitive tissues and central nervous system.

Samidorphan mitigates olanzapine-induced weight gain and metabolic dysfunction in rats and non-human primates

BACKGROUND

Olanzapine, regarded as one of the most efficacious antipsychotic medications for the treatment of schizophrenia, is associated with a high risk of weight gain and metabolic dysfunction. ALKS 3831, a clinical candidate for treatment of schizophrenia, is a combination of olanzapine and samidorphan, an opioid receptor antagonist. The addition of samidorphan is intended to mitigate weight gain and the metabolic dysregulation associated with the use of olanzapine.

METHODS

Non-clinical studies were conducted to assess the metabolic effects of olanzapine and samidorphan alone and in combination at clinically relevant exposure levels.

RESULTS

Chronic olanzapine administration in male and female rats shifted body composition by increasing adipose mass, which was accompanied by an increase in the rate of weight gain in female rats. Co-administration of samidorphan normalized body composition in both sexes and attenuated weight gain in female rats. In hyperinsulinemic euglycemic clamp experiments conducted prior to measurable changes in weight and/or body composition, olanzapine decreased hepatic insulin sensitivity and glucose uptake in muscle while increasing uptake in adipose tissue. Samidorphan appeared to normalize glucose utilization in both tissues, but did not restore hepatic insulin sensitivity. In subsequent studies, samidorphan normalized olanzapine-induced decreases in whole-body glucose clearance following bolus insulin administration. Results from experiments in female monkeys paralleled the effects in rats.

CONCLUSIONS

Olanzapine administration increased weight gain and adiposity, both of which were attenuated by samidorphan. Furthermore, the combination of olanzapine and samidorphan prevented olanzapine-induced insulin insensitivity. Collectively, these data indicate that samidorphan mitigates several metabolic abnormalities associated with olanzapine in both the presence and the absence of weight gain.

Preclinical and Clinical Sex Differences in Antipsychotic-Induced Metabolic Disturbances: A Narrative Review of Adiposity and Glucose Metabolism

Antipsychotic (AP) medications are associated with an increased risk of developing metabolic side effects including weight gain, type 2 diabetes (T2D), dyslipidemia, and hypertension. In the majority of clinical studies, females on APs are noted to gain more weight, and are more likely to be diagnosed with metabolic syndrome when compared to males. However, the data is less clear when comparing sex disparities associated with other specific AP-induced metabolic risk factors. Accumulating evidence has demonstrated a role for AP-induced adipose tissue accumulation as well as whole body glucose dysregulation in male models that is independent of changes in body weight. The purpose of this narrative review is to explore the susceptibility of males and females to changes in adiposity and glucose metabolism across clinical and preclinical models of AP treatment. It is important that future research examining AP-induced metabolic side effects analyzes outcomes by sex to help clarify risk and identify the mechanisms of adverse event development to improve safe prescribing of medications.

Brain insulin action: Implications for the treatment of schizophrenia

Insulin action in the central nervous system is a major regulator of energy balance and cognitive processes. The development of central insulin resistance is associated with alterations in dopaminergic reward systems and homeostatic signals affecting food intake, glucose metabolism, body weight and cognitive performance. Emerging evidence has highlighted a role for antipsychotics (APs) to modulate central insulin-mediated pathways. Although APs remain the cornerstone treatment for schizophrenia they are associated with severe metabolic complications and fail to address premorbid cognitive deficits, which characterize the disorder of schizophrenia. In this review, we first explore how the hypothesized association between schizophrenia and CNS insulin dysregulation aligns with the use of APs. We then investigate the proposed relationship between CNS insulin action and AP-mediated effects on metabolic homeostasis, and different domains of psychopathology, including cognition. We briefly discuss a potential role of CNS insulin signaling to explain the hypothesized, but somewhat controversial association between therapeutic efficacy and metabolic side effects of APs. Finally, we propose how this knowledge might inform novel treatment strategies to target difficult to treat domains of schizophrenia. This article is part of the issue entitled 'Special Issue on Antipsychotics'.

Antipsychotics and glucose metabolism: how brain and body collide

Since the serendipitous discovery of the first antipsychotic (AP) drug in the 1950s, APs remain the cornerstone of treatment for schizophrenia. A shift over the past two decades away from first-generation, conventional APs to so-called "atypical" (or 2nd/3rd generation) APs parallels acknowledgment of serious metabolic side-effects associated in particular with these newer agents. As will be reviewed, AP drugs and type 2 diabetes are now inextricably linked, contributing to the three- to fivefold increased risk of type 2 diabetes observed in schizophrenia. However, this association is not straightforward. Biological and lifestyle-related illness factors contribute to the association between type 2 diabetes and metabolic disease independently of AP treatment. In addition, APs have a well-established weight gain propensity which could also account for elevated risk of insulin resistance and type 2 diabetes. However, compelling preclinical and clinical evidence now suggests that these drugs can rapidly and directly influence pathways of glucose metabolism independently of weight gain and even in absence of psychiatric illness. Mechanisms of these direct effects remain poorly elucidated but may involve central and peripheral antagonism of neurotransmitters implicated not only in the therapeutic effects of APs but also in glucose homeostasis, possibly via effects on the autonomic nervous system. The clinical relevance of studying "direct" effects of these drugs on glucose metabolism is underscored by the widespread use of these medications, both on and off label, for a growing number of mental illnesses, extending safety concerns well beyond schizophrenia.

Atypical Antipsychotics and the Human Skeletal Muscle Lipidome

Atypical antipsychotics (AAPs) are a class of medications associated with significant metabolic side effects, including insulin resistance. The aim of this study was to analyze the skeletal muscle lipidome of patients on AAPs, compared to mood stabilizers, to further understand the molecular changes underlying AAP treatment and side effects. Bipolar patients on AAPs or mood stabilizers underwent a fasting muscle biopsy and assessment of insulin sensitivity. A lipidomic analysis of total fatty acids (TFAs), phosphatidylcholines (PCs) and ceramides (CERs) was performed on the muscle biopsies, then lipid species were compared between treatment groups, and correlation analyses were performed with insulin sensitivity. TFAs and PCs were decreased and CERs were increased in the AAP group relative to those in the mood stabilizer group (FDR q-value <0.05). A larger number of TFAs and PCs were positively correlated with insulin sensitivity in the AAP group compared to those in the mood stabilizer group. In contrast, a larger number of CERs were negatively correlated with insulin sensitivity in the AAP group compared to that in the mood stabilizer group. The findings here suggest that AAPs are associated with changes in the lipid profiles of human skeletal muscle when compared to mood stabilizers and that these changes correlate with insulin sensitivity.

Metabolic side effects of atypical antipsychotics in older adults

ABSTRACTBackground:The atypical antipsychotics (AAPs) are associated with a recognized class effect of glucose and lipid dysregulation. The use of these medications is rapidly increasing in elderly patients with, and without, dementia. However, the metabolic risks specific to elderly remain poorly studied.

METHODS

Design: A case-control study.

SETTING

Psychogeriatric service in Auckland, New Zealand.

PARTICIPANTS

Elderly patients either receiving AAP treatment (cases) or not (controls) between 1 Jan 2008 and 1 Jan 2014.

MAIN OUTCOME MEASURES

metabolic data of glucose, HbA1c, lipids, and cardiovascular events and death. The data were analyzed using t-tests and linear regression models for each metabolic outcome.

RESULTS

There were 330 eligible cases and 301 controls from a total study population of 5,307. There was a statistically significant change in the HbA1c over time, within the cases group of -1.14 mmol/mol (p = 0.018, 95% CI -0.19 to -2.09). Also statistically significant was the reduction in total cholesterol of -0.13 mmol/L (p = 0.036, 95% CI -0.008 to -0.245). The only significant difference found between cases and controls was in the change in cholesterol ratio of 0.16 mmol/L between groups (95%CI 0.01-0.31, p = 0.036).

CONCLUSIONS

AAP use was not associated with any clinically significant change in metabolic outcomes in this study population.

Atypical antipsychotics, insulin resistance and weight; a meta-analysis of healthy volunteer studies

Atypical antipsychotics increase the risk of diabetes and cardiovascular disease through their side effects of insulin resistance and weight gain. The populations for which atypical antipsychotics are used carry a baseline risk of metabolic dysregulation prior to medication which has made it difficult to fully understand whether atypical antipsychotics cause insulin resistance and weight gain directly. The purpose of this work was to conduct a systematic review and meta-analysis of atypical antipsychotic trials in healthy volunteers to better understand their effects on insulin sensitivity and weight gain. Furthermore, we aimed to evaluate the occurrence of insulin resistance with or without weight gain and with treatment length by using subgroup and meta-regression techniques. Overall, the meta-analysis provides evidence that atypical antipsychotics decrease insulin sensitivity (standardized mean difference=-0.437, p<0.001) and increase weight (standardized mean difference=0.591, p<0.001) in healthy volunteers. It was found that decreases in insulin sensitivity were potentially dependent on treatment length but not weight gain. Decreases in insulin sensitivity occurred in multi-dose studies <13days while weight gain occurred in studies 14days and longer (max 28days). These findings provide preliminary evidence that atypical antipsychotics cause insulin resistance and weight gain directly, independent of psychiatric disease and may be associated with length of treatment. Further, well-designed studies to assess the co-occurrence of insulin resistance and weight gain and to understand the mechanisms and sequence by which they occur are required.

The microbiome-gut-brain axis: implications for schizophrenia and antipsychotic induced weight gain

With the emergence of knowledge implicating the human gut microbiome in the development and regulation of several physiological systems, evidence has accumulated to suggest a role for the gut microbiome in psychiatric conditions and drug response. A complex relationship between the enteric nervous system, the gut microbiota and the central nervous system has been described which allows for the microbiota to influence and respond to a variety of behaviors and psychiatric conditions. Additionally, the use of pharmaceuticals may interact with and alter the microbiota to potentially contribute to adverse effects of the drug. The gut microbiota has been described in several psychiatric disorders including depression and anxiety, but only a few reports have discussed the role of the microbiome in schizophrenia. The following review examines the evidence surrounding the gut microbiota in behavior and psychiatric illness, the role of the microbiota in schizophrenia and the potential for antipsychotics to alter the gut microbiota and promote adverse metabolic events.

In male rats, the ability of central insulin to suppress glucose production is impaired by olanzapine, whereas glucose uptake is left intact

BACKGROUND

Insulin receptors are widely expressed in the brain and may represent a crossroad between metabolic and cognitive disorders. Although antipsychotics, such as olanzapine, are the cornerstone treatment for schizophrenia, they are associated with high rates of type 2 diabetes and lack efficacy for illness-related cognitive deficits. Historically, this risk of diabetes was attributed to the weight gain propensity of antipsychotics, but recent work suggests antipsychotics can have weight-independent diabetogenic effects involving unknown brain-mediated mechanisms. Here, we examined whether antipsychotics disrupt central insulin action, hypothesizing that olanzapine would impair the well-established ability of central insulin to supress hepatic glucose production.

METHODS

Pancreatic euglycemic clamps were used to measure glucose kinetics alongside a central infusion of insulin or vehicle into the third ventricle. Male rats were pretreated with olanzapine or vehicle per our established model of acute olanzapine-induced peripheral insulin resistance. Groups included (central-peripheral) vehicle-vehicle (n = 11), insulin-vehicle (n = 10), insulin-olanzapine (n = 10) and vehicle-olanzapine (n = 8).

RESULTS

There were no differences in peripheral glucose or insulin levels. Unexpectedly, we showed that central insulin increased glucose uptake, and this effect was not perturbed by olanzapine. We replicated suppression of glucose production by insulin (clamp relative to basal: 77.9% ± 13.1%, all p < 0.05), an effect abolished by olanzapine (insulin-olanzapine: 7.7% ± 14%).

LIMITATIONS

This study used only male rats and an acute dose of olanzapine.

CONCLUSION

To our knowledge, this is the first study suggesting olanzapine may impair central insulin sensing, elucidating a potential mechanism of antipsychotic-induced diabetes and opening avenues of investigation related to domains of schizophrenia psychopathology.

Glucagon receptor knockout mice are protected against acute olanzapine-induced hyperglycemia

OBJECTIVES

To determine if glucagon is involved in mediating the increase in blood glucose levels caused by the second-generation antipsychotic drug olanzapine.

MATERIALS AND METHODS

Whole body glucagon receptor deficient mice (Gcgr^-/-) or WT littermate controls were injected with olanzapine (5mg/kg BW IP) and changes in blood glucose measured over the following 120min. Separate cohorts of mice were treated with olanzapine and changes in pyruvate tolerance, insulin tolerance and whole body substrate oxidation were determined.

RESULTS

Olanzapine treatment increased serum glucagon and lead to rapid increases in blood glucose concentrations in WT mice. Gcgr^-/- mice were protected against olanzapine-induced increases in blood glucose but this was not explained by differences in terminal serum insulin concentrations, enhanced AKT phosphorylation in skeletal muscle, adipose tissue or liver or differences in RER. In both genotypes olanzapine induced an equivalent degree of insulin resistance as measured using an insulin tolerance test. Olanzapine treatment led to an exaggerated glucose response to a pyruvate challenge in WT but not Gcgr^-/- mice and this was paralleled by reductions in the protein content of PEPCK and G6Pase in livers from Gcgr^-/- mice.

CONCLUSIONS

Gcgr^-/- mice are protected against olanzapine-induced increases in blood glucose. This is likely a result of reductions in liver glucose output, perhaps secondary to decreases in PEPCK and G6Pase protein content. Our findings highlight the central role of the liver in mediating olanzapine-induced disturbances in glucose homeostasis.

Metabolic Response to Olanzapine in Healthy Chinese Subjects with rs7093146 Polymorphism in Transcription Factor 7-like 2 Gene (TCF7L2): A Prospective Study

Olanzapine is a widely used atypical antipsychotic with significant weight gain and other metabolic side effects. The locus of the transcription factor 7-like 2 (TCF7L2) gene is strongly associated with type 2 diabetes (T2D). The goal of this study was to determine whether polymorphic TCF7L2 is involved in the susceptibility to the metabolic changes associated with the atypical antipsychotic agents (AAPs). In this study, a parallel clinical study with 3-day consecutive administration of olanzapine (10 mg/day) was conducted in 17 healthy subjects with a genotype of TCF7L2 rs7903146 CC (N = 10) or CT (N = 7). Olanzapine caused rapid metabolic changes including body-weight gain, increased triglycerides level and reduced HDL-cholesterol level in the healthy subjects. rs7093146 T carriers (CT) were found to have greater AUC_{0-2 hr} of insulin during OGTT compared to those (CC) bearing only reference alleles before and after olanzapine treatment. However, the triglyceride level in the subjects with the CT genotype was found to be significantly lower than that in the subjects with CC genotype. Moreover, a significant interaction between the effect by genotype and that by olanzapine treatment on triglyceride level was identified. Acute olanzapine treatment also significantly caused total protein, albumin and haemoglobin decrease and uric acid increase in the healthy subjects. In conclusion, even acute olanzapine treatment induces significant and rapid metabolic changes, and TCF7L2 polymorphism is a genetic risk factor of olanzapine-associated metabolic side effects.

Olanzapine-induced early cardiovascular effects are mediated by the biological clock and prevented by melatonin

Second generation antipsychotics (SGA) are associated with adverse cardiometabolic side effects contributing to premature mortality in patients. While mechanisms mediating these cardiometabolic side effects remain poorly understood, three independent studies recently demonstrated that melatonin was protective against cardiometabolic risk in SGA-treated patients. As one of the main target areas of circulating melatonin in the brain is the suprachiasmatic nucleus (SCN), we hypothesized that the SCN is involved in SGA-induced early cardiovascular effects in Wistar rats. We evaluated the acute effects of olanzapine and melatonin in the biological clock, paraventricular nucleus and autonomic nervous system using immunohistochemistry, invasive cardiovascular measurements, and Western blot. Olanzapine induced c-Fos immunoreactivity in the SCN followed by the paraventricular nucleus and dorsal motor nucleus of the vagus indicating a potent induction of parasympathetic tone. The involvement of a SCN-parasympathetic neuronal pathway after olanzapine administration was further documented using cholera toxin-B retrograde tracing and vasoactive intestinal peptide immunohistochemistry. Olanzapine-induced decrease in blood pressure and heart rate confirmed this. Melatonin abolished olanzapine-induced SCN c-Fos immunoreactivity, including the parasympathetic pathway and cardiovascular effects while brain areas associated with olanzapine beneficial effects including the striatum, ventral tegmental area, and nucleus accumbens remained activated. In the SCN, olanzapine phosphorylated the GSK-3β, a regulator of clock activity, which melatonin prevented. Bilateral lesions of the SCN prevented the effects of olanzapine on parasympathetic activity. Collectively, results demonstrate the SCN as a key region mediating the early effects of olanzapine on cardiovascular function and show melatonin has opposing and potentially protective effects warranting additional investigation.

Metabolic Syndrome Prevalence and Reduction in Inmates Prescribed Antipsychotic Medications

The principal aim of this study was to establish whether a metabolic monitoring program implemented for second-generation antipsychotic medications (SGAs) was associated with any reduction in the prevalence of metabolic syndrome in adult inmates treated with antipsychotic medications in the New Jersey Department of Corrections. The average prevalence of metabolic syndrome in those prescribed SGAs decreased from 17.9% during the years before metabolic monitoring to 14.3% during the years of monitoring. The number of patients prescribed antipsychotic medication decreased a net 35% over 9 years of the study. We conclude that metabolic monitoring was one of the several administrative interventions over the study period that reduced the unnecessary exposure of inmates to the risks of antipsychotic medications.

Atypical antipsychotics: recent research findings and applications to clinical practice: Proceedings of a symposium presented at the 29th Annual European College of Neuropsychopharmacology Congress, 19 September 2016, Vienna, Austria

Available evidence suggests that second-generation atypical antipsychotics are broadly similar to first-generation agents in terms of their efficacy, but may have a more favourable tolerability profile, primarily by being less likely to cause extrapyramidal symptoms. However, atypical antipsychotics are variably associated with disturbances in the cardiometabolic arena, including increased body weight and the development of metabolic syndrome, which may reflect differences in their receptor binding profiles. Effective management of schizophrenia must ensure that the physical health of patients is addressed together with their mental health. This should therefore involve consideration of the specific tolerability profiles of available agents and individualization of treatment to minimize the likelihood of adverse metabolic sequelae, thereby improving long-term adherence and optimizing overall treatment outcomes. Alongside this, modifiable risk factors (such as exercise, diet, obesity/body weight and smoking status) must be addressed, in order to optimize patients' overall health and quality of life (QoL). In addition to antipsychotic-induced side effects, the clinical management of early nonresponders and psychopharmacological approaches for patients with treatment-resistant schizophrenia remain important unmet needs. Evidence suggests that antipsychotic response starts early in the course of treatment and that early nonresponse accurately predicts nonresponse over the longer term. Early nonresponse therefore represents an important modifiable risk factor for poor efficacy and effectiveness outcomes, since switching or augmenting antipsychotic treatment in patients showing early nonresponse has been shown to improve the likelihood of subsequent treatment outcomes. Recent evidence has also demonstrated that patients showing early nonresponse to treatment with lurasidone at 2 weeks may benefit from an increase in dose at this timepoint without compromising tolerability/safety. However, further research is required to determine whether these findings are generalizable to other antipsychotic agents.

Chronic Olanzapine Treatment Induces Disorders of Plasma Fatty Acid Profile in Balb/c Mice: A Potential Mechanism for Olanzapine-Induced Insulin Resistance

Background

Atypical antipsychotics such as olanzapine cause metabolic side effects leading to obesity and insulin resistance. The underlying mechanisms remain elusive. In this study we investigated the effects of chronic treatment of olanzapine on the fatty acid composition of plasma in mice.

Methods

Twenty 8-week female Balb/c mice were randomly assigned to two groups: the OLA group and the control group. After treatment with olanzapine (10 mg/kg/day) or vehicle intraperitoneally for 8 weeks, fasting glucose, insulin levels and oral glucose tolerance test were determined. Effects on plasma fatty acid profile and plasma indices of D5 desaturase, D6 desaturase and SCD1 activity were also investigated.

Results

Chronic administration of olanzapine significantly elevated fasting glucose and insulin levels, impaired glucose tolerance, but did not increase body weight. Total saturated fatty acids and n-6 polyunsaturated fatty acids were significantly increased and total monounsaturated fatty acids were significantly decreased, while total n-3 polyunsaturated fatty acids showed no prominent changes. Chronic olanzapine treatment significantly up-regulated D6 desaturase activity while down-regulating D5 desaturase activity. Palmitic acid (C16:0), dihomo-γ-linolenic acid (C20:3n-6) and D6 desaturase were associated with an increase probability of insulin resistance, whereas nervonic acid (C24:1) and SCD1 were significantly associated with a lower insulin resistance probability.

Conclusions

All results indicated that such drug-induced effects on fatty acid profile in plasma were relevant for the metabolic adverse effects associated with olanzapine and possibly other antipsychotics. Further studies are needed to investigate geneticand other mechanisms to explain how plasma fatty acids regulate glucose metabolism and affect the risk of insulin resistance.

Current Data on and Clinical Insights into the Treatment of First Episode Nonaffective Psychosis: A Comprehensive Review

Implementing the most suitable treatment strategies and making appropriate clinical decisions about individuals with a first episode of psychosis (FEP) is a complex and crucial task, with relevant impact in illness outcome. Treatment approaches in the early stages should go beyond choosing the right antipsychotic drug and should also address tractable factors influencing the risk of relapse. Effectiveness and likely metabolic and endocrine disturbances differ among second-generation antipsychotics (SGAs) and should guide the choice of the first-line treatment. Clinicians should be aware of the high risk of cardiovascular morbidity and mortality in schizophrenia patients, and therefore monitoring weight and metabolic changes across time is mandatory. Behavioral and counseling interventions might be partly effective in reducing weight gain and metabolic disturbances. Ziprasidone and aripiprazole have been described to be least commonly associated with weight gain or metabolic changes. In addition, some of the SGAs (risperidone, amisulpride, and paliperidone) have been associated with a significant increase of plasma prolactin levels. Overall, in cases of FEP, there should be a clear recommendation of using lower doses of the antipsychotic medication. If no or minimal clinical improvement is found after 2 weeks of treatment, such patients may benefit from a change or augmentation of treatment. Clinicians should provide accurate information to patients and relatives about the high risk of relapse if antipsychotics are discontinued, even if patients have been symptom free and functionally recovered on antipsychotic treatment for a lengthy period of time.

Dietary Fructose and GLUT5 Transporter Activity Contribute to Antipsychotic-Induced Weight Gain

Receptors for antipsychotics in the hypothalamus contribute to antipsychotics-induced weight gain; however, many of these receptors are also expressed in the intestine. The role of these intestinally-expressed receptors, and their potential modulation of nutrient absorption, have not been investigated in the context of antipsychotics-induced weight gain. Here we tested the effect of dietary fructose and intestinal fructose uptake on clozapine-induced weight gain in mice. Weight gain was determined in wild type mice and mice lacking the GLUT5 fructose transporter that were "orally-administered" 20mg/kg clozapine for 28 days. To assess the role of dietary fructose, clozapine-treated mice were fed controlled diets with different levels of fructose. Effect of clozapine treatment on intestinal fructose transport activity and expression levels of various receptors that bind clozapine, as well as several genes involved in gluconeogenesis and lipogenesis were measured using real-time RT-PCR and western blotting. Oral administration of clozapine significantly increased body weight in wild type C57BL/6 mice but not in GLUT5 null mice. The clozapine-induced weight gain was proportional to the percentage of fructose in the diet. Clozapine-treated mice increased intestinal fructose uptake without changing the intestinal expression level of GLUT5. Clozapine-treated mice expressed significantly higher levels of intestinal H1 histamine receptor in the wild type but not GLUT5 null mice. Clozapine also increased the intestinal expression of fructokinase and several genes involved in gluconeogenesis and lipogenesis. Our results suggest that increased intestinal absorption and metabolism of fructose contributes to clozapine-induced weight gain. Eliminating dietary fructose might prevent antipsychotics-induced weight gain.

Olanzapine Is Faster than Haloperidol in Inducing Metabolic Abnormalities in Schizophrenic and Bipolar Patients

The effects of olanzapine and haloperidol on metabolic parameters in bipolar patients have been evaluated much less comprehensively than in schizophrenic patients. Therefore, in this study, medical records of 343 schizophrenic and bipolar patients treated with haloperidol or olanzapine for 1 year were retrospectively reviewed and metabolic outcomes were evaluated. After 12 months of follow-up, 25.9% of patients showed ≥3 metabolic abnormalities with a point prevalence of 27.2% in the bipolar and 24.9% in the schizophrenic group: 22.0% of the schizophrenic patients treated with haloperidol and 29.8% of those treated with olanzapine achieved ≥3 metabolic alterations; in bipolar patients, these percentages were 15.8% of those treated with haloperidol and 37.8% of those treated with olanzapine (p < 0.0001). Significant changes were reported over time in fasting glucose, triglycerides and cholesterol blood levels, systolic and diastolic blood pressure, body weight, and BMI. Overall, a significant number of schizophrenic and bipolar patients treated with olanzapine showed ≥3 metabolic alterations in the first month of treatment when compared to those treated with haloperidol. Moreover, the number of olanzapine-treated patients developing metabolic changes in the first month was significantly higher in both diagnostic groups when compared to those who reached metabolic abnormal values in the subsequent 11 months. These data suggest that both antipsychotics could increase the metabolic risk in schizophrenic and bipolar patients with a higher prevalence in olanzapine-treated patients. On the other hand, olanzapine-treated patients seem to achieve metabolic abnormalities faster than haloperidol-treated subjects in both diagnostic groups.

Adiposity-independent hypoadiponectinemia as a potential marker of insulin resistance and inflammation in schizophrenia patients treated with second generation antipsychotics

OBJECTIVE

The purpose of this study was to explore body fat independent effect of second generation antipsychotics (SGAs) on measures of glucose and adipokine homeostasis, and markers of inflammation.

METHOD

Eight non-diabetic men with schizophrenia (age: 55±3years, BMI: 29.7±1.2kg/m(2)) on SGAs were studied after an overnight fast. DXA and single-cut CT of abdomen were respectively used for the assessment of total body and abdominal fat. Blood samples were collected for measurements of glucose, insulin, leptin, adiponectin, C-reactive protein (CRP), and TNF-α. Data in schizophrenic subjects were compared to eight age (55±2.8years) and BMI (29.6±1.1kg/m(2)) matched healthy men.

RESULTS

The results were significant for markedly decreased serum adiponectin in schizophrenia patients (4.6±0.9 vs 11.1±1.5ng/mL, p=0.001). Lower levels of adiponectin in schizophrenia men were associated with significant increases in insulin resistance (4.2±0.7 vs 1.7±0.4, p=0.004), CRP (3.5±1.2 vs 1.2±0.3, p=0.037), and leptin (12±1.4 vs 8.5±1.4ng/mL, p=0.05). Various measures of adiposity, including fat mass index (FMI) and abdominal fat were not different in the two study groups.

CONCLUSIONS

These findings in the context of comparable age and total body/abdominal fat mass are assumed to be either disease specific, and/or treatment inflicted. The definitive invoking etiology and a presumptive role of hypoadiponectinemia in the development of insulin resistance and increased risk of inflammation warrant future investigation.

A low TSH profile predicts olanzapine-induced weight gain and relief by adjunctive topiramate in healthy male volunteers

Second generation antipsychotics, like olanzapine (OLZ), have become the first line drug treatment for patients with schizophrenia. However, OLZ treatment is often associated with body weight (BW) gain and metabolic derangements. Therefore, the search for prospective markers for OLZ's negative side effects as well as adjunctive treatments to inhibit these has been of major interest. The aim of this study was to investigate in healthy male volunteers (age: 36 ± 11 years; BW: 84 ± 12 kg; BMI=25.5 ± 2.5) whether adjunctive topiramate (TPM) administration opposes OLZ-induced weight gain over the course of 14 days treatment. In addition, we investigated behavioral, endocrine and metabolic characteristics as underlying and potentially predictive factors for weight regulation and/or metabolic derangements associated with OLZ and TPM treatment. While adjunctive TPM indeed reduced OLZ-induced weight gain (P<0.05, Mann-Whitney U), behavioral/metabolic/endocrine characteristics of OLZ treatment were not affected by TPM. Using multiple regression analysis, BW gain was the key factor explaining metabolic disturbances (e.g., plasma insulin- LDL interaction: P<0.01, R(2)=.320), and cumulative food intake during treatment was the best denominator of BW gain (P<0.01, R(2)=.534). Neither TPM treatment, nor its circulating levels, contributed to variation observed in ΔBW. In a second multiple regression analysis, we observed that a low baseline thyrotropin profile (TSHAUC) before the start of drug treatment was associated with an increase in ΔBW over the course of drug treatment (P<0.05, R(2)=.195). Adding TSHAUC as covariate revealed that adjunctive TPM treatment did attenuate OLZ induced BW gain (P<0.05, ANCOVA). Further exploration of the circulating thyroid hormones revealed that individuals with a low plasma TSH profile were also those that were most sensitive to adjunctive TPM treatment blocking OLZ-induced ΔBW gain. Others have shown that OLZ-induced BW gain is associated with improvement in brief psychiatric rating scores (BPRS); adjunctive TPM treatment may be a solution specifically for those subjects susceptible to OLZ-induced rapid weight gain who-on a therapeutic level-benefit most of OLZ treatment.

Glucagon-like peptide-1 agonists combating clozapine-associated obesity and diabetes

Clozapine is the most effective antipsychotic, but its use is tempered by adverse metabolic effects such as weight gain, glucose intolerance and type II diabetes. Current interventions do not facilitate compelling or sustained improvement in metabolic status. Recent studies suggest that glucagon-like peptide-1 (GLP-1) may play a key role in clozapine's metabolic effects, possibly suggesting that clozapine-associated obesity and diabetes are mediated independently through reduced GLP-1. As a result, GLP-1 agonists could show promise in reversing antipsychotic-induced metabolic derangements, providing mechanistic justification that they may represent a novel approach to treat, and ultimately prevent, both diabetes and obesity in patients on clozapine. GLP-1 agonists are already used for diabetes, and they provide a unique combination of glycaemic improvement and metabolically relevant weight loss in diabetic and non-diabetic patients, in the context of a currently favourable safety profile. Using GLP-1 agonists for clozapine-associated obesity and diabetes could be a potentially effective intervention that may reduce cardiometabolic morbidity and mortality in this vulnerable patient population.

Common Medications Which Lead to Unintended Alterations in Weight Gain or Organ Lipotoxicity

Obesity is one of the most common chronic conditions in the world. Its management is difficult, partly due to the multiple associated comorbidities including fatty liver, diabetes, hypertension, and hyperlipidemia. As a result, the choice of prescription medications in overweight and obese patients has important implications as some of them can actually worsen the fat accumulation and its associated metabolic complications. Several prescription medications are associated with weight gain with mechanisms that are often poorly understood and under-recognized. Even less data are available on the distribution of fat and lipotoxicity (the organ damage related to fat accumulation). The present review will discuss the drugs associated with weight gain, their mechanism of action, and the magnitude and timing of their effect.

Life-threatening ketoacidosis in a pregnant woman with psychotic disorder

Pregnancy is an insulin resistant state. Hyperglycaemia and gestational diabetes mellitus are well-recognised complications even in women without existing metabolic syndrome or obesity. Pregnant women also appear to be more vulnerable to ketoacidosis, particularly after short periods of reduced oral intake in the third trimester, and may present with very severe starvation ketoacidosis, prompting emergent delivery. We present a case of a woman with a background of depression and psychotic episodes. Olanzapine had been commenced after a psychotic episode at 20 weeks' gestation. Gestational diabetes mellitus was diagnosed at 28 weeks, and she was then admitted at 31 weeks with severe euglycaemic ketoacidosis following a short period of vomiting. She underwent caesarean section when the metabolic disturbances did not resolve with medical treatment. We believe atypical antipsychotic therapy contributed to the profound insulin resistance seen here, and that obstetricians, physicians and psychiatrists must be aware of the risks conferred by these agents in pregnancy.

Kimberley Indigenous mental health: An examination of metabolic syndrome risk factors

OBJECTIVE

There is an increased risk of physical health comorbidities in people with a mental illness. This paper examines the metabolic syndrome parameters for the general population, indigenous Australians and people with a mental illness, and compares them to a sample of predominantly indigenous adults with mental health problems.

DESIGN

A longitudinal (24 month) audit of patient medical records was conducted between February 2011 and March 2013.

SETTING

The Kimberley Mental Health and Drug Service in Broome, Western Australia.

PARTICIPANTS

Largely indigenous adults with a mental illness. Sample numbers increased from 56 at baseline (80% indigenous) to 136 at 18 months (70% indigenous).

MAIN OUTCOME MEASURES

Waist circumference, blood pressure, fasting lipids, and fasting blood glucose.

RESULTS

Preliminary assessment of the data indicates a high percentage of abnormalities at baseline and at the 18 month period on all four parameters, yet not all patients were assessed on a regular basis.

CONCLUSIONS

Abnormalities in metabolic profiles consistent with the non-Indigenous mental health population were found. There are considerable challenges to implementing regular monitoring of physical and metabolic profiles of indigenous people in rural and remote communities.

Metformin attenuates olanzapine-induced hepatic, but not peripheral insulin resistance

Antipsychotics (APs) are linked to diabetes, even without weight gain. Whether anti-diabetic drugs are efficacious in reversing the direct effects of APs on glucose pathways is largely undetermined. We tested two metformin (Met) doses to prevent impairments seen following a dose of olanzapine (Ola) (3 mg/kg); glucokinetics were measured using the hyperinsulinemic-euglycemic clamp (HIEC). Met (150 mg/kg; n=13, or 400 mg/kg; n=11) or vehicle (Veh) (n=11) was administered through gavage preceding an overnight fast, followed by a second dose prior to the HIEC. Eleven additional animals were gavaged with Veh and received a Veh injection during the HIEC (Veh/Veh); all others received Ola. Basal glucose was similar across treatment groups. The Met 400 group had significantly greater glucose appearance (Ra) in the basal period (i.e., before Ola, or hyperinsulinemia) vs other groups. During hyperinsulinemia, glucose infusion rate (GINF) to maintain euglycemia (reflective of whole-body insulin sensitivity) was higher in Veh/Veh vs other groups. Met 150/Ola animals demonstrated increased GINF relative to Veh/Ola during early time points of the HIEC. Glucose utilization during hyperinsulinemia, relative to basal conditions, was significantly higher in Veh/Veh vs other groups. The change in hepatic glucose production (HGP) from basal to hyperinsulinemia demonstrated significantly greater decreases in Veh/Veh and Met 150/Ola groups vs Veh/Ola. Given the increase in basal Ra with Met 400, we measured serum lactate (substrate for HGP), finding increased levels in Met 400 vs Veh and Met 150. In conclusion, Met attenuates hepatic insulin resistance observed with acute Ola administration, but fails to improve peripheral insulin resistance. Use of supra-therapeutic doses of Met may mask metabolic benefits by increasing lactate.

RNA sequencing reveals a slow to fast muscle fiber type transition after olanzapine infusion in rats

Second generation antipsychotics (SGAs), like olanzapine, exhibit acute metabolic side effects leading to metabolic inflexibility, hyperglycemia, adiposity and diabetes. Understanding how SGAs affect the skeletal muscle transcriptome could elucidate approaches for mitigating these side effects. Male Sprague-Dawley rats were infused intravenously with vehicle or olanzapine for 24h using a dose leading to a mild hyperglycemia. RNA-Seq was performed on gastrocnemius muscle, followed by alignment of the data with the Rat Genome Assembly 5.0. Olanzapine altered expression of 1347 out of 26407 genes. Genes encoding skeletal muscle fiber-type specific sarcomeric, ion channel, glycolytic, O2- and Ca2+-handling, TCA cycle, vascularization and lipid oxidation proteins and pathways, along with NADH shuttles and LDH isoforms were affected. Bioinformatics analyses indicate that olanzapine decreased the expression of slower and more oxidative fiber type genes (e.g., type 1), while up regulating those for the most glycolytic and least metabolically flexible, fast twitch fiber type, IIb. Protein turnover genes, necessary to bring about transition, were also up regulated. Potential upstream regulators were also identified. Olanzapine appears to be rapidly affecting the muscle transcriptome to bring about a change to a fast-glycolytic fiber type. Such fiber types are more susceptible than slow muscle to atrophy, and such transitions are observed in chronic metabolic diseases. Thus these effects could contribute to the altered body composition and metabolic disease olanzapine causes. A potential interventional strategy is implicated because aerobic exercise, in contrast to resistance exercise, can oppose such slow to fast fiber transitions.

Preliminary Examination of Olanzapine and Diet Interactions On Metabolism in a Female Macaque

Clinical data suggest that atypical antipsychotics such as olanzapine (OLZ) induce significant metabolic changes that are serious side effects of their primary use. Since controlled human studies are problematic and rodent data may be poorly translatable, we have initiated development of a macaque model of OLZ-induced metabolic disease. In this preliminary feasibility study, we examined some metabolic effects of OLZ in a female macaque in the context of a standard low-calorie/fat monkey chow diet followed by a high-fat/sugar Western-style diet (WSD). A female Japanese macaque was administered OLZ (1.25 mg/day) for 6 months, with dietary changes at 2-month intervals as follows: OLZ+Restricted chow, OLZ+Unrestricted chow, OLZ+WSD, and placebo+WSD. Weight was assessed weekly. Glucose tolerance tests (GTT) and Dexascans were performed at baseline and every 2 months. Omental (OM) and subcutaneous (SQ) adipose tissue biopsies were obtained at baseline, after OLZ+Unrestricted chow and after OLZ+WSD to evaluate adipocyte size, lipolysis and insulin-stimulated free fatty acid uptake (FFA). A separate trial was conducted on 2 monkeys with 5 days of OLZ- or no-treatment followed by RT-PCR on rostral and medial basal hypothalamus. Weight increased on OLZ+Restricted chow and stabilized on OLZ+Unrestricted chow. OLZ+WSD did not significantly change the weight plateau. Weight declined upon withdrawal of OLZ with continued WSD. Body fat increased from 14% at baseline to 22%, 30%, 28% and 19% at 2, 4, 6 and 8 mo, respectively, indicating that body fat was elevated on OLZ regardless of diet and declined upon OLZ removal. Glucose tolerance and the insulin response during GTT were normal with OLZ+Restricted chow or OLZ+Unrestricted chow. Addition of WSD with OLZ impaired glucose clearance during GTT. Insulin remained in the normal range, but first phase insulin secretion was reduced. After removal of OLZ, but continued WSD, glucose clearance returned to normal, but this was associated with hyperinsulinemia. Adipocyte diameter was increased in OM and SQ fat by OLZ+chow and OLZ+WSD to a similar extent. (p<0.01, 2-way ANOVA). In OM, isoproterenol-stimulated lipolysis occurred at baseline. In both depots, isoproterenol-stimulated lipolysis occurred with OLZ+chow, but it was significantly blunted by addition of WSD (ANOVA p<0.0001; posthoc p<0.05). Insulin increased FFA uptake at baseline. OLZ +chow or OLZ+WSD increased basal FFA uptake and insulin-induced FFA uptake was blunted in both depots (posthoc p<0.05). There was a marked decrease in POMC gene expression, and increased AgRP and NPY expression in the hypothalamus. There was also a clear increase in serotonin (5HT) 2C, melanocortin (MCR4), and Leptin (LepR) receptor gene expression. These data support the hypotheses that OLZ acts on peripheral tissues as well as in the CNS; that changes in hypothalamic gene expression occur very rapidly and precede increased fat accumulation; that adipose tissue exhibits insulin resistance prior to alterations in GTT; that addition of WSD to OLZ precipitates hyperglycemia without an obvious insulin response; and that removal of OLZ and continued WSD resulted in normalized glucose clearance and elevated insulin. These data suggest complex and early responses to OLZ that may be exacerbated by WSD.

Antipsychotics-induced metabolic alterations: focus on adipose tissue and molecular mechanisms

The use of antipsychotic drugs for the treatment of mood disorders and psychosis has increased dramatically over the last decade. Despite its consumption being associated with beneficial neuropsychiatric effects in patients, atypical antipsychotics (which are the most frequently prescribed antipsychotics) use is accompanied by some secondary adverse metabolic effects such as weight gain, dyslipidemia and glucose intolerance. The molecular mechanisms underlying these adverse effects are not fully understood but have been suggested to involve a dysregulation of adipose tissue homeostasis. As such, the aim of this paper is to review and discuss the role of adipose tissue in the development of secondary adverse metabolic effects induced by atypical antipsychotics. Data analyzed in this article suggest that atypical antipsychotics may increase adipose tissue (particularly visceral adipose tissue) lipogenesis, differentiation/hyperplasia, pro-inflammatory mediator secretion and insulin resistance and decrease adipose tissue lipolysis. Consequently, patients receiving antipsychotic medication could be at risk of developing obesity, type 2 diabetes and cardiovascular disease. A better knowledge of the impact of these drugs on adipose tissue homeostasis may unveil strategies to develop novel antipsychotic drugs with less adverse metabolic effects and to develop adjuvant therapies (e.g. behavioral and nutritional therapies) to neuropsychiatric patients receiving antipsychotic medication.

Atypical antipsychotic-induced metabolic disturbances in the elderly

The metabolic side effects of atypical antipsychotics (AAPs) have been widely studied in younger populations, but research investigating these sequelae in the elderly is lacking. This article reviews the available literature examining the use of AAPs in the elderly, evaluating their association with weight gain and changes in blood glucose and lipid parameters. We find a relative paucity of studies in this area; while some data highlight significant, collective changes in metabolic parameters, the majority suggests an apparent low vulnerability to these side effects. We conclude that the risk and clinical implications of unfavorable metabolic changes in the elderly being treated with AAP medications remain largely undetermined, and we caution against drawing firm conclusions based on the available data. The conflicting evidence leaves us recommending that metabolic monitoring be implemented, with regular follow-up as advocated in other populations.

An evaluation of the effects of the novel antipsychotic drug lurasidone on glucose tolerance and insulin resistance: a comparison with olanzapine

Over the past two decades, there has been a notable rise in the use of antipsychotic drugs, as they are used to treat an increasing number of neuropsychiatric disorders. This rise has been led predominantly by greater use of the second generation antipsychotic (SGA) drugs, which have a low incidence of neurological side-effects. However, many SGAs cause metabolic dysregulation, including glucose intolerance and insulin resistance, thus increasing the risk of cardiometabolic disorders. The metabolic effects of the novel SGA lurasidone, which was approved by the Food and Drug Administration in 2010, remain largely unknown. As rodent models accurately predict the metabolic effects of SGAs in humans, the aim of the present study was to use sophisticated animal models of glucose tolerance and insulin resistance to measure the metabolic effects of lurasidone. In parallel, we compared the SGA olanzapine, which has established metabolic effects. Adult female rats were treated with vehicle, lurasidone (0.2, 0.8 or 2.0 mg/kg, s.c.) or olanzapine (10.0 mg/kg, s.c.) and subjected to the glucose tolerance test (GTT). Separate groups of rats were treated with vehicle, lurasidone (0.2, 0.8 or 2.0 mg/kg, s.c.) or olanzapine (1.5 and 15 mg/kg, s.c.) and tested for insulin resistance with the hyperinsulinemic-euglycemic clamp (HIEC). Compared to vehicle treated animals, lurasidone caused mild glucose intolerance in the GTT with a single dose, but there was no effect on insulin resistance in the GTT, measured by HOMA-IR. The HIEC also confirmed no effect of lurasidone on insulin resistance. In contrast, olanzapine demonstrated dose-dependent and potent glucose intolerance, and insulin resistance in both tests. Thus, in preclinical models, lurasidone demonstrates mild metabolic liability compared to existing SGAs such as olanzapine. However, confirmation of these effects in humans with equivalent tests should be confirmed.

Clozapine directly increases insulin and glucagon secretion from islets: implications for impairment of glucose tolerance

Second generation antipsychotics cause derangements in glucose metabolism that are often interpreted as insulin resistance. In previous studies we have shown that this is not classical insulin resistance but the drugs were actually inducing a hyperglycaemic state associated with elevated hepatic glucose output (HGO) and increased levels of glucagon and insulin. However, it remains unclear whether these effects are directly elicited by drug actions in the liver and pancreas, or whether they are indirectly mediated. Here we investigated if clozapine is capable of inducing insulin resistance in the liver or enhancing insulin and glucagon secretion from the pancreas. It was observed that insulin signalling was elevated in livers from animals treated with clozapine indicating there was no insulin resistance in the early steps of insulin signalling. To explore whether the defects arise at later stages of insulin action we used an isolated perfused liver system. In this model, clozapine had no direct effect on insulin's counter regulatory effect on epinephrine-induced HGO. In isolated mouse islets clozapine significantly increased glucose-stimulated insulin secretion while simultaneously blocking glucose-induced reductions in glucagon secretion. We also show that the non-peptidic glucagon receptor like peptide-1 (GLP-1) receptor agonist Boc5 was able to overcome the inhibitory effects of clozapine on glucose metabolism. Taken together these results suggest that clozapine does not have any direct effect on glucose metabolism in the liver but it simultaneously stimulates insulin and glucagon secretion, a situation that would allow for the concurrent presence of high glucose and high insulin levels in treated animals.

Obesity and Serious Mental Ill Health: A Critical Review of the Literature

Individuals who experience serious mental ill health such as schizophrenia are more likely to be overweight or obese than others in the general population. This high prevalence of obesity and other associated metabolic disturbances, such as type 2 diabetes and cardiovascular disease, contribute to a reduced life expectancy of up to 25 years. Several reasons have been proposed for high levels of obesity including a shared biological vulnerability between serious mental ill health and abnormal metabolic processes, potentially compounded by unhealthy lifestyles. However, emerging evidence suggests that the most significant cause of weight gain is the metabolic side effects of antipsychotic medication, usual treatment for people with serious mental ill health. In this paper we review the prevalence of obesity in people with serious mental ill health, explore the contribution that antipsychotic medication may make to weight gain and discuss the implications of this data for future research and the practice of mental health and other professionals.

Effects of intracerebroventricular (ICV) olanzapine on insulin sensitivity and secretion in vivo: an animal model

The atypical antipsychotics (AAPs) have been associated with an increased risk of type 2 diabetes. While weight gain associated with AAPs is a risk factor for diabetes, preclinical work suggests that among these medications, olanzapine, when given peripherally in a single dose, causes pronounced effects on insulin sensitivity and secretion. Given a critical role of the hypothalamus in control of glucose metabolism, we examined the effect of central administration of olanzapine. Sprague-Dawley rats were treated with a single 75 μg intracerebroventricular (ICV) dose of olanzapine and tested using separate hyperinsulinemic-euglycemic and hyperglycemic clamps. Dosing of olanzapine was established based on inhibition of amphetamine-induced locomotion. In contrast to the single dosing peripheral paradigm, there was no effect of central olanzapine on insulin sensitivity, either with respect to hepatic glucose production or peripheral glucose uptake. Analogous to the peripheral model, a single ICV dose of olanzapine followed by the hyperglycemic clamp decreased insulin (p=0.0041) and C-peptide response (p=0.0039) to glucose challenge as compared to vehicle, mirrored also by a decrease in the steady state glucose infusion rate required to maintain hyperglycemia (p=0.002). In conclusion, we demonstrate novel findings that at least part of the effect of olanzapine on beta-cell function in vivo is central.

Routine exercise ameliorates the metabolic side-effects of treatment with the atypical antipsychotic drug olanzapine in rats

Second generation antipsychotic (SGA) drugs are effective treatments for psychosis. Common side-effects of SGAs include metabolic dysregulation and risk of cardiometabolic disorders. Metabolic side-effects, including glucose intolerance, can be accurately modelled in rodents. The benefits of interventions used for treating metabolic side-effects of SGAs are mostly unknown. In a 9 wk longitudinal study, female rats were given daily olanzapine (10 mg/kg s.c.) or vehicle. Animals were either sedentary or allowed 1 or 3 h daily access to a running wheel, with total wheel revolutions electronically quantified to reflect exercise intensity. Glucose tolerance tests were performed once weekly to measure glycemic control. Drug levels were measured at week 4. At week 9, abdominal fat and skeletal muscle levels of Glucose Transporter 4 (GLUT4) were measured. Exercise intensity progressively increased over time in all groups given access to running wheels; however, rats treated with olanzapine consistently exercised less than those given the vehicle. Olanzapine caused acute and persistent glucose intolerance throughout the study, which was markedly, though incompletely, ameliorated by exercise. Exercise did not affect glycemic regulation in vehicle-treated rats. Olanzapine-treated rats showed greater central adiposity. Levels of GLUT4 in skeletal muscle were higher in both groups of exercising than in sedentary rats, and GLUT4 values were negatively correlated with glucose intolerance. Routine exercise reduced olanzapine-induced glucose intolerance and increased skeletal muscle levels of GLUT 4, the insulin-responsive transporter that mediates glucose uptake into cells. The current animal model is suitable for evaluating physiological pathways involved with glucose intolerance.