Olanzapine as a prophylactic antiemetic for preventing postoperative nausea and vomiting after general anesthesia: A systematic review and meta-analysis.

BACKGROUND: The antiemetic effectiveness of olanzapine, as a prophylactic off-label antiemetic drug, for Postoperative Nausea and Vomiting (PONV) is unknown. In this systematic review and meta-analysis, the authors evaluate the efficacy and side effects of olanzapine as a prophylactic antiemetic in adult patients who undergo general anesthesia and assess adverse effects. METHODS: A systematic search was done on electronic bibliographic databases in July 2023. Randomized controlled trials of olanzapine as a prophylactic antiemetic for PONV in adults who underwent general anesthesia were included. The authors excluded non-RCTs and retracted studies. The authors set no date of publication or language limits. The outcomes were the incidence of PONV within 24 h postoperatively and the safety of olanzapine. The risk of bias was assessed according to the tool suggested by the National Heart, Lung, and Blood Institute. RESULTS: Meta-analysis included 446 adult patients. Olanzapine reduced on average 38 % the incidence of PONV. The estimated risk ratio (95 % CI) of olanzapine versus control was 0.62 (0.42-0.90), p = 0.010, I2 = 67 %. In the subgroup meta-analysis, doses of olanzapine (10 mg) reduced on average 49 % of the incidence of PONV (RR = 0.51 [0.34-0.77], p = 0.001, I2 = 31 %). CONCLUSIONS: This systematic review with meta-analysis indicated that olanzapine as a prophylactic antiemetic alone or combined with other antiemetic agents reduced the incidence of postoperative nausea and vomiting. However, this conclusion must be presented with some degree of uncertainty due to the small number of studies included. There was a lack of any evidence to draw conclusions on side effects.

Efficacy and tolerability of FDA-approved atypical antipsychotics for the treatment of bipolar depression: a systematic review and network meta-analysis.

We employed a Bayesian network meta-analysis for comparison of the efficacy and tolerability of US Food and Drug Administration (FDA)-approved atypical antipsychotics (AAPs) for the treatment of bipolar patients with depressive episodes. Sixteen randomized controlled trials with 7234 patients treated by one of the five AAPs (cariprazine, lumateperone, lurasidone, olanzapine, and quetiapine) were included. For the response rate (defined as an improvement of ≥50% from baseline on the Montgomery-Åsberg Depression Rating Scale [MADRS]), all AAPs were more efficacious than placebo. For the remission rate (defined as the endpoint of MADRS ≤12 or ≤ 10), cariprazine, lurasidone, olanzapine, and quetiapine had higher remission rates than placebo. In terms of tolerability, olanzapine was unexpectedly associated with lower odds of all-cause discontinuation in comparison with placebo, whereas quetiapine was associated with higher odds of discontinuation due to adverse events than placebo. Compared with placebo, lumateperone, olanzapine, and quetiapine showed higher odds of somnolence. Lumateperone had a lower rate of ≥ weight gain of 7% than placebo and other treatments. Olanzapine was associated with a significant increase from baseline in total cholesterol and triglycerides than placebo. These findings inform individualized prescriptions of AAPs for treating bipolar depression in clinical practice.

Refeeding syndrome and psychopharmacological interventions in children and adolescents with Anorexia Nervosa: a focus on olanzapine-related modifications of electrolyte balance.

This study aims to investigate the potential correlation between the use of olanzapine, a psychopharmacological intervention commonly prescribed in Anorexia Nervosa treatment, and the occurrence of Refeeding Syndrome. Despite the acknowledged nutritional and biochemical impacts of olanzapine, the literature lacks information regarding its specific association with Refeeding Syndrome onset in individuals with Anorexia Nervosa. This is a naturalistic, retrospective, observational study, reporting the occurrence of Refeeding Syndrome in children and adolescents with Anorexia Nervosa, treated or untreated with olanzapine. Dosages and serum levels of olanzapine were assessed for potential associations with the occurrence of Refeeding Syndrome and specific variations in Refeeding Syndrome-related electrolytes. Overall, 113 patients were enrolled, including 46 (41%) who developed a Refeeding Syndrome. Mild (87%), moderate (6.5%), and severe (6.5%) Refeeding Syndrome was described, at a current average intake of 1378 ± 289 kcal/day (39 ± 7.7 kcal/kg/die), frequently associated with nasogastric tube (39%) or parenteral (2.2%) nutrition. Individuals receiving olanzapine experienced a more positive phosphorus balance than those who did not (F(1,110) = 4.835, p = 0.030), but no difference in the occurrence of Refeeding Syndrome was documented. The mean prescribed doses and serum concentrations of olanzapine were comparable between Refeeding Syndrome and no-Refeeding Syndrome patients.    Conclusion: The present paper describes the occurrence of Refeeding Syndrome and its association with olanzapine prescriptions in children and adolescents with Anorexia Nervosa. Olanzapine was associated with a more positive phosphorus balance, but not with a different occurrence of Refeeding Syndrome. Further, longitudinal studies are required. What is Known: • Refeeding Syndrome (RS) is a critical complication during refeeding in malnourished patients, marked by electrolyte (phosphorus, magnesium, potassium) imbalances. • Olanzapine, an atypical antipsychotic with nutritional and biochemical impacts, is used in Anorexia Nervosa (AN) treatment, however data concerning its association with RS are lacking. What is New: • The study observed RS in 46/113 (41%) young patients with AN. • Olanzapine-treated individuals showed a higher improvement in serum phosphate levels than untreated ones, although no impact on the occurrence of Refeeding Syndrome was observed.

PCSK9 dysregulates cholesterol homeostasis and triglyceride metabolism in olanzapine-induced hepatic steatosis via both receptor-dependent and receptor-independent pathways.

Schizophrenia, affecting approximately 1% of the global population, is often treated with olanzapine. Despite its efficacy, olanzapine's prolonged use has been associated with an increased risk of cardiovascular diseases and nonalcoholic fatty liver disease (NAFLD); however, the underlying mechanism remains unclear. Proprotein convertase subtilisin kexin type 9 (PCSK9) plays a crucial role in lipid metabolism and is involved in NAFLD pathogenesis via an unknown mechanism. This study aims to investigate the role of PCSK9 in olanzapine-induced NAFLD. C57BL/6J mice and HepG2 and AML12 cell lines were treated with varying concentrations of olanzapine to examine the effects of olanzapine on PCSK9 and lipid metabolism. PCSK9 levels were manipulated using recombinant proteins, plasmids, and small interfering RNAs in vitro, and the effects on hepatic lipid accumulation and gene expression related to lipid metabolism were assessed. Olanzapine treatment significantly increased PCSK9 levels in both animal and cell line models, correlating with elevated lipid accumulation. PCSK9 manipulation demonstrated its central role in mediating hepatic steatosis through both receptor-dependent pathways (impacting NPC1L1) and receptor-independent pathways (affecting lipid synthesis, uptake, and cholesterol biosynthesis). Interestingly, upregulation of SREBP-1c, rather than SREBP-2, was identified as a key driver of PCSK9 increase in olanzapine-induced NAFLD. Our findings establish PCSK9 as a pivotal factor in olanzapine-induced NAFLD, influencing both receptor-related and metabolic pathways. This highlights PCSK9 inhibitors as potential therapeutic agents for managing NAFLD in schizophrenia patients treated with olanzapine.

B-GOS alleviates olanzapine-induced lipid disturbances in mice by enriching Akkermansia and upregulation of PGRMC1-Wnt signaling.

Although olanzapine (OLZ) remains one of the most efficacious antipsychotic medications for the treatment of schizophrenia, there are significant tolerability issues related to its metabolic profile such as weight gain and dyslipidemia. Our previous studies have demonstrated that progesterone receptor membrane component 1 (PGRMC1) plays a key role in antipsychotic-induced metabolic side effects. Prebiotics showed positive effects on lipid metabolism, however, limited studies focused on their therapeutic potential and mechanisms in treating antipsychotic-induced lipid metabolic disorders. Herein, our study aims to explore the effects of the prebiotic B-GOS on lipid disturbances induced by OLZ and elucidate its underlying mechanisms via PGRMC1 pathway. In an 8-week study, long-term intraperitoneal administration of OLZ at a dosage of 8 mg/kg/day in mice induced lipid disturbances as manifested by significantly increased lipid indexes in plasma and liver. B-GOS effectively alleviated the OLZ-induced abnormal lipid metabolism by enhancing the diversity of the gut microbiota, with a 100-fold increase in Akkermansia abundance and a 10-fold decrease in Faecalibaculum abundance. Followed by the B-GOS related changes of gut microbiota, OLZ-induced substantial hepatic inhibition of PGRMC1, and associated protein factors of Wnt signaling pathway (Wnt3a, ß-catenin, and PPAR-γ) were reversed without affecting plasma levels of short-chain fatty acids. Taken together, prebiotics like B-GOS enriching Akkermansia offer a promising novel approach to alleviate antipsychotic-induced lipid disturbances by modulating the PGRMC1-Wnt signaling pathway.

Group-Based Trajectory Modeling to Identify Patterns of Antipsychotic-Associated Weight Gain Among Children and Adolescents.

PURPOSE/BACKGROUND: Antipsychotic-associated weight gain (AAWG) is a common adverse effect of second-generation antipsychotic (SGA) medications among children and adolescents. This study applied group-based trajectory modeling to identify latent trajectories of AAWG among children and adolescents and associated risk factors. PROCEDURES: This was a retrospective analysis of the IQVIA Ambulatory EMR-US database from 2016 to 2021. The cohort consisted of patients aged 6 to 19 years who were SGA naive and received at least 90 days of continuous SGA prescriptions. Group-based trajectory modeling was used to identify latent trajectories of AAWG development during a 24-month period since SGA initiation, and multinomial logistic regression analysis was conducted to examine the risk factors associated with the identified AAWG trajectories. FINDINGS/RESULTS: A total of 16,262 patients were included. Group-based trajectory modeling identified the following 4 distinctive AAWG trajectories: persistent severe weight gain (4.2%), persistent moderate weight gain (20.1%), minor weight change (69.6%), and gradual weight loss (6.1%). Compared with the minor weight change group, younger age (12-17 vs 5-11: odds ratio [OR], 0.634; 95% confidence interval [CI], 0.521-0.771), lower baseline body mass index z -score (OR, 0.216; 95% CI, 0.198-0.236), and receiving olanzapine as the initial SGA (olanzapine vs aripiprazole: OR, 1.686; 95% CI, 1.673-1.699) were more likely to follow severe weight gain trajectories. The area under the receiver operating characteristic curves for comparing severe weight gain versus minor weight change groups and moderate weight vs minor weight change groups in the multinomial regression model were 0.91 and 0.8, respectively. IMPLICATIONS/CONCLUSIONS: A quarter of pediatric SGA recipients experienced persistent weight gain during the SGA treatment. The risk of having persistent AAWG can be predicted using patient characteristics collected before SGA initiation and the initial SGA agent.

Dexamethasone-Free Antiemetic Prophylaxis for Highly Emetogenic Chemotherapy: A Double-Blind, Phase III Randomized Controlled Trial (CINV POD study).

PURPOSE: The effectiveness of a dexamethasone (DEX)-free regimen for chemotherapy-induced nausea and vomiting (CINV) prophylaxis in patients receiving highly emetogenic chemotherapy (HEC) is not known. METHODS: This was a double-blind, phase III trial designed to show the noninferiority of a DEX-free regimen (olanzapine, palonosetron, and fosaprepitant [OPF]) compared with the DEX-containing regimen (olanzapine, palonosetron, and DEX [OPD]). Chemotherapy-naïve patients age 18-80 years receiving single-day HEC were randomly assigned 1:1 to receive either the OPD regimen or the OPF regimen. The primary objective was to compare complete response (CR) rates for vomiting during the overall period (start of chemotherapy to 120 hours). Secondary objectives included CR for vomiting during the acute period (0-24 hours) and delayed period (24-120 hours), CR for nausea, and comparison of toxicities and patient-reported outcomes. RESULTS: Three hundred forty-six patients received the study interventions, 174 in the OPD arm and 172 in the OPF arm. The DEX-free OPF arm had significantly higher CR rates for vomiting compared with the DEX-containing OPD arm in acute (94.7% v 85.6%; P < .004), delayed (81.9% v 50.5%; P < .001), and overall (79.6% v 48.8%; P < .001) periods. For nausea, CR rates in the OPF arm were higher in delayed (53.4% v 39.6%; P = .009) and overall (50.5% v 39.1%; P = .031) periods but not in the acute period (77.9% v 81.6%; P = .39). Fatigue (P = .009) and drowsiness (P = .002) were more in the OPF arm in the acute period and insomnia (P < .001) in the OPD arm in the overall period. CONCLUSION: This study shows that a DEX-free OPF regimen is efficacious and should be considered a standard option for acute and delayed CINV prophylaxis for HEC.

The effect of continuous theta burst stimulation on antipsychotic-induced weight gain in first-episode drug-naive individuals with schizophrenia: a double-blind, randomized, sham-controlled feasibility trial.

Antipsychotic intake may induce weight gain in drug-naive individuals with schizophrenia, leading to poor compliance in clinical management. However, there is still a lack of effective approaches to treat or prevent this side-effect. Therefore, we conducted this pilot study to investigate the effect of continuous theta burst stimulation (cTBS), a non-invasive magnetic stimulation technique, on preventing olanzapine-induced weight gain. Thirty-nine first-episode drug-naive individuals with schizophrenia were randomly assigned to receive either the active or sham cTBS intervention for 25 sessions (5 times per day for 5 consecutive days). The primary outcomes were changes in body weight and body mass index (BMI). Secondary outcomes included psychiatric symptoms, eating behavior scales, behavior tasks, and metabolic measures. For the result, the body weight and BMI increased significantly in the sham group but not in the active group, with a significant group effect. The active group exhibited a selective increase in the cognitive restraint domain in the Three-Factor Eating Questionnaire (TFEQ-CR) and a decrease in stop-signal reaction time compared to the sham group. The effect of cTBS on body weight was mediated by TFEQ-CR. Our findings demonstrated the feasibility that cTBS intervention could be a potential method for preventing olanzapine-induced weight gain in drug-naive first-episode schizophrenia patients through enhancing cognitive restraint to food. Trial registration: clinical trial registered with clinicaltrials.gov (NCT05086133).

Low-dose versus standard-dose olanzapine with triple antiemetic therapy for prevention of highly emetogenic chemotherapy-induced nausea and vomiting in patients with solid tumours: a single-centre, open-label, non-inferiority, randomised, controlled, phase 3 trial.

BACKGROUND: Olanzapine is an effective antiemetic agent but it results in substantial daytime somnolence when administered at the standard dose. Our aim was to compare the efficacy of low-dose versus standard-dose olanzapine after highly emetogenic chemotherapy in patients with solid tumours. METHODS: This was a single-centre, open-label, non-inferiority, randomised, controlled, phase 3 trial done in a tertiary care referral centre in India (Tata Memorial Centre, Homi Bhabha National Institute, Mumbai). Patients aged 13-75 years with an Eastern Cooperative Oncology Group performance status of 0-2, who were receiving doxorubicin-cyclophosphamide or high-dose cisplatin for a solid tumour were eligible. Patients were randomly assigned (1:1), with block randomisation (block sizes of 2 or 4) and stratified by sex, age (≥55 or <55 years), and chemotherapy regimen, to receive low-dose (2·5 mg) oral olanzapine or standard-dose (10·0 mg) oral olanzapine daily for 4 days, in combination with a triple antiemetic regimen. Study staff were masked to treatment allocation but patients were aware of their group assignment. The primary endpoint was complete control, defined as no emetic episodes, no rescue medications, and no or mild nausea in the overall phase (0-120 hours), assessed in the modified intention-to-treat (mITT) population (ie, all eligible patients who received protocol-specified treatment, excluding those who had eligibility violations and who withdrew consent after randomisation). Daytime somnolence was the safety endpoint of interest. Non-inferiority was shown if the upper limit of the one-sided 95% CI for the difference in the complete control proportions between the treatment groups excluded the non-inferiority margin of 10%. This study is registered with the Clinical Trial Registry India, CTRI/2021/01/030233, is closed to accrual, and this is the final data analysis. RESULTS: Between Feb 9, 2021, and May 30, 2023, 356 patients were pre-screened for eligibility, of whom 275 patients were enrolled and randomly assigned (134 to the 2·5 mg olanzapine group and 141 to the 10·0 mg olanzapine group). 267 patients (132 in the 2·5 mg group and 135 in the 10·0 mg group) were included in the mITT population, of whom 252 (94%) were female, 15 (6%) were male, and 242 (91%) had breast cancer. 59 (45%) of 132 patients in the 2·5 mg olanzapine group had complete control in the overall phase versus 59 (44%) of 135 in the 10·0 mg olanzapine group (difference -1·0% [one-sided 95% CI -100·0 to 9·0]; p=0·87). In the overall phase, there were significantly fewer patients in the 2·5 mg olanzapine group than in the 10·0 mg olanzapine group with daytime somnolence of any grade (86 [65%] of 132 vs 121 [90%] of 135; p<0·0001) and of severe grade on day 1 (six]5%] vs 54 [40%]; p<0·0001). INTERPRETATION: Our findings suggest that olanzapine 2·5 mg is non-inferior to 10·0 mg in antiemetic efficacy and results in reduced occurrence of daytime somnolence among patients receiving highly emetic chemotherapy and should be considered as a new standard of care. FUNDING: Progressive Ladies Welfare Association.

Olanzapine attenuates 5-HT2cR and GHSR1a interaction to increase orexigenic hypothalamic NPY: Implications for neuronal molecular mechanism of metabolic side effects of antipsychotics.

The main cause of second-generation antipsychotic (SGA)-induced obesity is considered due to the antagonism of serotonin 2c receptors (5-HT2cR) and activation of ghrelin receptor type 1a (GHSR1a) signalling. It is reported that 5-HT2cR interacted with GHSR1a, however it is unknown whether one of the SGA olanzapine alters the 5-HT2cR/GHSR1a interaction, affecting orexigenic neuropeptide signalling in the hypothalamus. We found that olanzapine treatment increased average energy intake and body weight gain in mice; olanzapine treatment also increased orexigenic neuropeptide (NPY) and GHSR1a signaling molecules, pAMPK, UCP2, FOXO1 and pCREB levels in the hypothalamus. By using confocal fluorescence resonance energy transfer (FRET) technology, we found that 5-HT2cR interacted/dimerised with the GHSR1a in the hypothalamic neurons. As 5-HT2cR antagonist, both olanzapine and S242084 decreased the interaction between 5-HT2cR and GHSR1a and activated GHSR1a signaling. The 5-HT2cR agonist lorcaserin counteracted olanzapine-induced attenuation of interaction between 5-HT2cR and GHSR1a and inhibited activation of GHSR1a signalling and NPY production. These findings suggest that 5-HT2cR antagonistic effect of olanzapine in inhibition of the interaction of 5-HT2cR and GHSR1a, activation GHSR1a downstream signaling and increasing hypothalamic NPY, which may be the important neuronal molecular mechanism underlying olanzapine-induced obesity and target for prevention metabolic side effects of antipsychotic management in psychiatric disorders.

Involvement of Extracellular Vesicles in the Proinflammatory Response to Clozapine: Implications for Clozapine-Induced Agranulocytosis.

Most idiosyncratic drug reactions (IDRs) appear to be immune-mediated, but mechanistic events preceding severe reaction onset remain poorly defined. Damage-associated molecular patterns (DAMPs) may contribute to both innate and adaptive immune phases of IDRs, and changes in extracellular vesicle (EV) cargo have been detected post-exposure to several IDR-associated drugs. To explore the hypothesis that EVs are also a source of DAMPs in the induction of the immune response preceding drug-induced agranulocytosis, the proteome and immunogenicity of clozapine- (agranulocytosis-associated drug) and olanzapine- (non-agranulocytosis-associated drug) exposed EVs were compared in two preclinical models: THP-1 macrophages and Sprague-Dawley rats. Compared with olanzapine, clozapine induced a greater increase in the concentration of EVs enriched from both cell culture media and rat serum. Moreover, treatment of drug-naïve THP-1 cells with clozapine-exposed EVs induced an inflammasome-dependent response, supporting a potential role for EVs in immune activation. Proteomic and bioinformatic analyses demonstrated an increased number of differentially expressed proteins with clozapine that were enriched in pathways related to inflammation, myeloid cell chemotaxis, wounding, transforming growth factor-ß signaling, and negative regulation of stimuli response. These data indicate that, although clozapine and olanzapine exposure both alter the protein cargo of EVs, clozapine-exposed EVs carry mediators that exhibit significantly greater immunogenicity. Ultimately, this supports the working hypothesis that drugs associated with a risk of IDRs induce cell stress, release of proinflammatory mediators, and early immune activation that precedes severe reaction onset. Further studies characterizing EVs may elucidate biomarkers that predict IDR risk during development of drug candidates. SIGNIFICANCE STATEMENT: This work demonstrates that clozapine, an idiosyncratic drug-induced agranulocytosis (IDIAG)-associated drug, but not olanzapine, a safer structural analogue, induces an acute proinflammatory response and increases extracellular vesicle (EV) release in two preclinical models. Moreover, clozapine-exposed EVs are more immunogenic, as measured by their ability to activate inflammasomes, and contain more differentially expressed proteins, highlighting a novel role for EVs during the early immune response to clozapine and enhancing our mechanistic understanding of IDIAG and other idiosyncratic reactions.

Evaluation of palonosetron, fosaprepitant, and olanzapine as antiemetic prophylaxis for fludarabine and melphalan-based conditioning regimens prior to allogeneic hematopoietic stem cell transplants.

BACKGROUND: Limited data are available regarding efficacious antiemetic regimens to prevent chemotherapy-induced nausea and vomiting (CINV) for patients undergoing allogeneic hematopoietic stem cell transplant (HSCT). In patients aged 60 years or older, allogeneic HSCT is associated with improved survival, but tolerability of the transplant is a significant barrier. Fludarabine and melphalan (Flu-Mel) is a frequently utilized multi-day reduced intensity conditioning regimen for allogeneic HSCT. However, the optimal CINV prevention regimen is unknown. OBJECTIVE: The purpose of this study was to evaluate the efficacy of a novel CINV prophylaxis regimen prior to allogeneic HSCT with Flu-Mel compared to a historical control group. STUDY DESIGN: This was a retrospective, single-center, cohort review of 123 patients who received a Flu-Mel preparative regimen prior to allogeneic HSCT from January 1, 2019, to September 30, 2022. Fifty-nine patients received high dose ondansetron (HDO) for CINV prevention, while sixty-four patients received a combination of palonosetron, fosaprepitant, and olanzapine (PFO). The primary outcome was average number of rescue antiemetic doses administered per day. A key secondary outcome was time to first rescue antiemetic. RESULTS: The median number of antiemetic doses used per day was significantly lower in patients who received PFO compared to HDO (1.94 doses [0.31-3.60] vs 3.31 doses [1.61-4.92]; p = 0.002). In addition, use of PFO significantly prolonged the median time to first rescue antiemetic compared to HDO (41.3 h [24.3-122.7] vs 26.2 h [14.7-48.1]; p = 0.016). CONCLUSION: The combination of palonosetron, fosaprepitant, and olanzapine is an effective antiemetic regimen for patients receiving a Flu-Mel-based preparative regimen.

Activation of prefrontal parvalbumin interneurons ameliorates working memory deficit even under clinically comparable antipsychotic treatment in a mouse model of schizophrenia.

One of the critical unmet medical needs in schizophrenia is the treatment for cognitive deficits. However, the neural circuit mechanisms of them remain unresolved. Previous studies utilizing animal models of schizophrenia did not consider the fact that patients with schizophrenia generally cannot discontinue antipsychotic medication due to the high risk of relapse. Here, we used multi-dimensional approaches, including histological analysis of the prelimbic cortex (PL), LC-MS/MS-based in vivo dopamine D2 receptor occupancy analysis for antipsychotics, in vivo calcium imaging, and behavioral analyses of mice using chemogenetics to investigate neural mechanisms and potential therapeutic strategies for working memory deficit in a chronic phencyclidine (PCP) mouse model of schizophrenia. Chronic PCP administration led to alterations in excitatory and inhibitory synapses, specifically in dendritic spines of pyramidal neurons, vesicular glutamate transporter 1 (VGLUT1) positive terminals, and parvalbumin (PV) positive GABAergic interneurons located in layer 2-3 of the PL. Continuous administration of olanzapine, which achieved a sustained therapeutic window of dopamine D2 receptor occupancy (60-80%) in the striatum, did not ameliorate these synaptic abnormalities and working memory deficit in the chronic PCP-treated mice. We demonstrated that chemogenetic activation of PV neurons in the PL, as confirmed by in vivo calcium imaging, ameliorated working memory deficit in this model even under clinically comparable olanzapine treatment which by itself inhibited only PCP-induced psychomotor hyperactivity. Our study suggests that targeting prefrontal PV neurons could be a promising therapeutic intervention for cognitive deficits in schizophrenia in combination with antipsychotic medication.

Safety outcomes of antipsychotics classes in drug-naïve patients with first-episode schizophrenia: A nationwide cohort study in South Korea.

INTRODUCTION: Given the similar efficacies across antipsychotic medications for schizophrenia, understanding their safety profiles, particularly concerning receptor-binding differences, is crucial for optimal drug selection, especially for patients with first episode schizophrenia. We aimed to compare the safety outcomes of second-generation antipsychotics. METHODS: We conducted a retrospective cohort study with new user active comparator design using a nationwide claims database in South Korea. Participants were drug-naïve adult patients with first-episode schizophrenia. Three representative drugs with different pharmacologic profiles were compared: risperidone, olanzapine, and aripiprazole. Propensity scores were used to match the study groups, and the Cox proportional hazard model was used to calculate hazard ratios. Sensitivity analyses were performed in various epidemiological settings. Seventeen safety outcomes, including neuropsychiatric, cardiometabolic and gastrointestinal events, were assessed, with upper-respiratory-tract infection as a negative control outcome. RESULTS: A total of 1044, 2078, and 3634 participants were matched for olanzapine vs. risperidone, olanzapine vs. aripiprazole, and risperidone vs. aripiprazole comparisons, respectively. For parkinsonism, there was a significant difference in outcomes between the risperidone and aripiprazole groups (HR 1.80 [95% CI 1.13-2.91]), with consistent sensitivity analysis results. There were no significant differences in other neuropsychiatry outcomes or in the risk of cardiometabolic and gastrointestinal outcomes between any of the comparative group pairs. CONCLUSIONS: The risk of drug-induced parkinsonism was significantly higher with risperidone than with aripiprazole. Although olanzapine is known for its metabolic risk, there were no significant differences in risk between the other pairs.

HFD-exacerbated Metabolic Side Effects of Olanzapine Are Suppressed by ER Stress Inhibitor.

OBJECTIVE: Numerous schizophrenic patients are suffering from obesity primarily attributed to antipsychotic medication and poor dietary habits. This study investigated the progressive deterioration of olanzapine-induced metabolic disorders in the presence of a high-fat diet (HFD) and explored the involvement of endoplasmic reticulum (ER) stress. METHODS: Female Sprague-Dawley rats fed on a standard chow diet or HFD were treated with olanzapine (3 mg/kg/day) and the ER stress inhibitor 4-phenylbutyric acid (4-PBA, 1 and 0.5 g/kg/day) for 8 days. Changes in body weight, food intake, and plasma lipids were assessed. Hepatic fat accumulation was evaluated using oil red O staining. Western blotting and immunofluorescence assays were employed to examine the expression of ER stress markers, NOD-like receptor pyrin domain-containing protein 3 (NLRP3), and proopiomelanocortin (POMC) in the hypothalamus or liver. RESULTS: Compared to olanzapine alone, olanzapine+HFD induced greater weight gain, increased hyperlipidemia, and enhanced hepatic fat accumulation (P<0.05). Co-treatment with 4-PBA exhibited a dose-dependent inhibition of these effects (P<0.05). Further mechanistic investigations revealed that olanzapine alone activated ER stress, upregulated NLRP3 expression in the hypothalamus and liver, and downregulated hypothalamic POMC expression. The HFD exacerbated these effects by 50%-100%. Moreover, co-administration of 4-PBA dose-dependently attenuated the olanzapine+HFD-induced alterations in ER stress, NLRP3, and POMC expression in the hypothalamus and liver (P<0.05). CONCLUSION: HFD worsened olanzapine-induced weight gain and lipid metabolic disorders, possibly through ER stress-POMC and ER stress-NLRP3 signaling. ER stress inhibitors could be effective in preventing olanzapine+HFD-induced metabolic disorders.