Widespread reductions in cortical thickness following ketamine abuse.

BACKGROUND: Esketamine is a version of ketamine that has been approved for treatment-resistant depression, but our previous studies showed a link between non-medical use of ketamine and brain structural and functional alterations, including dorsal prefrontal grey matter reduction among chronic ketamine users. In this study, we sought to determine cortical thickness abnormalities following long-term, non-medical use of ketamine. METHODS: We acquired structural brain images for patients with ketamine use disorder and drug-free healthy controls. We used FreeSurfer software to measure cortical thickness for 68 brain regions. We compared cortical thickness between the 2 groups using analysis of covariance with covariates of age, gender, educational level, smoking, drinking, and whole-brain mean cortical thickness. RESULTS: We included images from 95 patients with ketamine use disorder and 169 controls. Compared with healthy controls, patients with ketamine use disorder had widespread decreased cortical thickness, with the most extensive reductions in the frontal (including the dorsolateral prefrontal cortex) and parietal (including the precuneus) lobes. Increased cortical thickness was not observed among ketamine users relative to comparison participants. Estimated total lifetime ketamine consumption was correlated with reductions in the right inferior parietal and the right rostral middle frontal cortical thickness. LIMITATIONS: We conducted a retrospective cross-sectional study, but longitudinal studies are needed to further validate decreased cortical thickness after nonmedical use of ketamine. CONCLUSION: This study provided evidence that, compared with healthy controls, chronic ketamine users have widespread reductions in cortical thickness. Our study underscores the importance of the long-term effects of ketamine on brain structure and serves as a reference for the antidepressant use of ketamine.

Association between childhood maltreatment and suicidal ideation among Chinese patients with chronic schizophrenia: the mediating role of insomnia.

BACKGROUND: Childhood maltreatment is a well-established transdiagnostic risk factor for suicidal ideation; however, previous studies on their association in schizophrenia have produced highly varied results. Moreover, the mechanism linking childhood maltreatment and suicide ideation remains unclear in schizophrenia. AIMS: This cross-sectional study aimed to investigate the association between childhood maltreatment and suicide ideation in people with schizophrenia and tested whether insomnia mediated this relationship. METHOD: Positive and Negative Syndrome Scale (PANSS), Insomnia Severity Index (ISI), Childhood Trauma Questionnaire - Short Form and Beck Suicidal Ideation Inventory were employed. Logistic regression and mediation analysis were performed. RESULTS: (a) The prevalence of suicide ideation, insomnia, sexual abuse, emotional neglect, emotional abuse, physical abuse and physical neglect was 10% (n = 61), 18% (n = 111), 11% (n = 68), 25% (n = 153), 6.3% (n = 39), 17% (n = 106) and 39% (n = 239), respectively. In all, 52% (n = 320) reported childhood maltreatment; (b) patients with suicide ideation demonstrated higher insomnia and childhood maltreatment. PANSS depression factor, ISI, lifetime suicidal attempts and emotional abuse were independently associated with suicide ideation; (c) insomnia partially mediated the effects of emotional abuse and emotional neglect on suicide ideation, and insomnia completely mediated the effects of physical neglect and physical abuse on suicide ideation. CONCLUSION: Our study calls for formal assessments for childhood maltreatment and insomnia in schizophrenia, which might help identify suicide ideation early. In addition, interventions targeting insomnia might help reduce suicide ideation among people with schizophrenia who experience childhood maltreatment.

Association of clinical variables and thyroid-stimulating hormone with psychotic symptoms in patients with first-episode and drug-naïve major depressive disorder with elevated fasting blood glucose: preliminary exploratory study with a large sample.

BACKGROUND: Psychotic symptoms and elevated fasting blood glucose (FBG) are frequently observed in people with major depressive disorder (MDD), but there is a lack of research into this relationship within this cohort. AIMS: This study aimed to preliminarily explore the prevalence of psychotic symptoms and their predictors among patients with MDD and elevated FBG. METHOD: This study enrolled 1718 patients with first-episode and drug-naïve (FEDN) MDD. Sociodemographic data and physical and biochemical indicators were collected. Clinical symptoms were assessed with tools such as the Hamilton Rating Scale for Anxiety, Hamilton Rating Scale for Depression (HRSD) and Positive and Negative Syndrome Scale positive subscale. RESULTS: The odds ratio for psychotic symptoms in those with MDD and elevated FBG (18.7%) was 2.33 times higher than those with MDD without elevated FBG. Presence of psychotic symptoms was significantly correlated with HRSD score, suicide attempts, and total cholesterol and thyroid-stimulating hormone levels. The combination of HRSD score, suicide attempts and thyroid-stimulating hormone levels among patients with MDD and elevated FBG effectively distinguished between individuals with and without psychotic symptoms, achieving an area under the curve of 0.87. CONCLUSIONS: Psychotic symptoms are frequently observed among FEDN MDD patients with elevated FBG, and depressive symptoms, suicide attempts and thyroid-stimulating hormone levels are related to psychotic symptoms in this cohort.

Memristor-based circuit design of episodic memory neural network and its application in hurricane category prediction.

Episodic memory, as a type of long-term memory (LTM), is used to learn and store the unique personal experience. Based on the episodic memory biological mechanism, this paper proposes a bionic episodic memory memristive neural network circuit. The proposed memristive neural network circuit includes a neocortical module, a parahippocampal module and a hippocampus module. The neocortical module with the two paths structure is used to receive the sensory signal, and is also used to separate and transmit the spatial information and the non-spatial information involved in the sensory signal. The parahippocampal module is composed of the parahippocampal cortex-MEA and the perirhinal cortex-LEA, which receives the two types of information from the neocortical module respectively. As the last module, the hippocampus module receives and integrates the output information of the parahippocampal module as well as generates the corresponding episodic memory. Meanwhile, the specific scenario information with the certain temporal signal from the generated episodic memory is also extracted by the hippocampus module. The simulation results in PSPICE show that the proposed memristive neural network circuit can generate the various episodic memories and extract the specific scenario information successfully. By configuring the memristor parameters, the proposed bionic episodic memory memristive neural network circuit can be applied to the hurricane category prediction, which verifies the feasibility of this work.

Altered spontaneous neurological activity in methamphetamine use disorders and its association with cognitive function.

BACKGROUND: Methamphetamine (MA) is a widely used and detrimental drug, yet the precise mechanisms by which MA affects cognitive function remain unclear. This study aims to investigate the relationship between cognitive function and brain functional imaging in individuals with MA use disorder (MUD). METHODS: This study involved 45 patients diagnosed with MUD and 43 healthy controls (HC). Cognitive function assessment utilized the MATRICS Consensus Cognitive Battery, and functional data were acquired using a 3.0 Tesla magnetic resonance imaging scanner. RESULTS: The MUD group exhibited lower regional homogeneity (ReHo) values in the bilateral postcentral, the left superior temporal, and the left lingual regions compared to the HC group. Additionally, the MUD group displayed higher amplitude of low-frequency fluctuation (ALFF) values in the bilateral fusiform and the left putamen compared to the HC group, along with lower ALFF values in the bilateral postcentral cortices and the left middle cingulate cortex compared to the HC group (all p < 0.05, with false discovery rate corrected). Linear regression analysis revealed a positive correlation between the ReHo value in the right postcentral cortex and the neuropsychology assessment battery-mazes test (p = 0.014). Furthermore, the ALFF value in the left putamen showed negative correlations with the scores of the digit-symbol coding test (p = 0.027), continuous performance test (p = 0.037), and battery-mazes test (p = 0.024). CONCLUSION: Patients with MUD exhibit altered brain spontaneous neurological activities, and the intensity of spontaneous neurological activity in the left putamen is strongly associated with cognitive function.

Employing Bayesian analysis to establish a cut-off point and assess stigma prevalence in substance use disorder: a comprehensive study of the Chinese version of the Substance Use Stigma Mechanism Scale.

PURPOSE: In China, individuals with substance use disorders (SUD) face severe stigma, but reliable stigma assessment tool is lacking. Therefore, this study aimed to validate the Chinese version of the Substance Use Stigma Mechanism Scale (SU-SMS-C) and set its cut-off point. METHODS: We recruited 1005 individuals with SUDs from Chinese rehabilitation centers. These participants completed a battery of questionnaires that included the SU-SMS-C, The Multidimensional Scale of Perceived Social Support (MSPSS), Center for Epidemiologic Studies Depression Scale (CES-D), General Self-Efficacy Scale (GSES), and Perceived Devaluation and Discrimination (PDD). Confirmatory factor analysis was used to assess the construct validity of the scale. Additionally, the Naive Bayes classifier was used to establish the cut-off point for the SU-SMS-C. We additionally explored the correlation between patient demographic characteristics and stigma. RESULTS: A confirmatory factor analysis was utilized, revealing a second-order five-factor model. Based on the Naive Bayes classifier, the area under the receiver operating characteristic (AUCROC) of 0.746, the cut-off point for the SU-SMS-C was established at 44.5. The prevalence of stigma observed in the study population was 49.05%. Significant disparities were observed in the distribution of stigma across genders, with males experiencing more pronounced stigma than females. Moreover, patients consuming different primary substances reported diverse levels of stigma. Notably, those primarily using heroin endured a higher degree of stigma than users of other substances. CONCLUSION: The study is the first to identify a cut-off point for the SU-SMS-C by Naive Bayes classifier, bridging a major gap in stigma measurement research. SU-SMS-C may help treat and manage SUDs by reducing stigma.

Serial multiple mediating roles of anxiety and thyroid-stimulating hormone in the relationship between depression and psychotic symptoms in young adults with anxious depression.

BACKGROUND: Psychotic symptoms (PS) frequently occur in young adults with anxious depression (AD), yet the mediators of the associations between depression and PS remain unclear. This study aimed to investigate the prevalence and risk factors of PS in first-episode and drug-naïve (FEDN) young adults with AD and attempted to elucidate the relationship between thyroid-stimulating hormone (TSH) levels, anxiety, depression, and PS, as well as to identify potential mediating roles. METHODS: 369 FEDN young adults with AD were recruited. Clinical symptoms were assessed using the Positive and Negative Syndrome Scale's positive subscale, the Hamilton Depression Rating Scale (HAMD), and the Hamilton Anxiety Rating Scale (HAMA). Fasting glucose, lipids, and thyroid function were also collected. RESULTS: The prevalence of PS in young adults with AD (21.68 %) was 12.24 times higher than in non-AD patients. The HAMD scores (P = 0.005, OR = 1.23), HAMA scores (P < 0.001, OR = 1.62), and TSH levels (P = 0.025, OR = 1.20) were significant predictors of PS. The combined area under the curve value for distinguishing young adults with AD with and without PS was 0.86. We also identified serial multiple mediating effects of TSH levels and anxiety on the association of depression with PS. CONCLUSIONS: These findings emphasize the role of anxiety and TSH levels as serial mediators of the association between depression and PS. Therefore, when treating PS in young adults with AD, it is important to focus not only on depression, but also on TSH levels and anxiety to maximize benefit.

Polysomnographic features of insomnia occurring in major depressive disorder, generalized anxiety disorder and bipolar mania: Comparison with primary insomnia and association with metabolic indicators.

BACKGROUND: Insomnia is very common in psychiatric disorders, but the polysomnographic (PSG) characteristics of insomnia in various psychiatric disorders are still not agreed upon. This study aimed to investigate the characteristics of PSG and its relationship with metabolic indicators in insomnia patients with affective disorders and primary insomnia (PI) patients. METHODS: A total of 38 patients with PI, 44 major depressive disorder patients with insomnia (DI), 49 generalized anxiety disorder patients with insomnia (GI), and 19 bipolar mania patients with insomnia (BI) were included. PSG was used to detect sleep problems in subjects, and biochemical indicators were also collected. RESULTS: The results of this study found that subjects with BI were lower on REM sleep latency (RL), awakenings number (AN), number of microarousals (NM), and apnea-hypopnea index (AHI) than those with DI and GI, and lower on RL and AN than those with PI. Subjects with PI had lower NM and AHI than those with DI and GI. Patients with DI had a higher RL than those with GI. All results passed Bonferroni correction (p < 0.00078). No differences in biochemical indices were found among the four groups of subjects. Also, AHI was found to be positively correlated with free triiodothyronine (FT3) and fasting blood glucose in subjects. CONCLUSION: This study suggests that various psychiatric disorders may have their characteristics in terms of PSG parameters, which prompted us to focus on the PSG characteristics of these disorders when assessing them, as well as to focus on their biochemical indicators.

Prevalence and risk factors for abnormal glucose metabolism in first-episode and drug-naïve major depressive disorder outpatients with comorbid anxiety: A cross-sectional study from a large sample of the Chinese Han population.

BACKGROUND: Both abnormal glucose metabolism and anxiety have been reported to be common in major depressive disorder (MDD). However, few studies have explored glucose disturbances in first-episode and drug-naive (FEDN) MDD patients with anxiety. The purpose of this study was to examine the prevalence and risk factors of glucose disturbance in FEND MDD patients comorbid with anxiety. METHODS: 1718 FEDN MDD patients were included in this study. The positive subscale of the Positive and Negative Syndrome Scale (PANSS), Hamilton Anxiety Rating Scale (HAMA), and Hamilton Depression Rating Scale (HAMD) were used to measure psychotic, anxiety and depressive symptoms respectively. Sociodemographic and biochemical indicators were also collected. RESULTS: The prevalence of glucose disorders in MDD patients combined with anxiety was 15.7 %, significantly higher than in MDD patients without anxiety symptoms (7.1 %). Glucose disturbances were associated with HAMD score, HAMA score, thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), anti-thyroglobulin (TGAb), total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein (LDL-C), fasting blood glucose (FBG), systolic blood pressure (SBP), diastolic blood pressure (DBP), suicide attempts, and psychotic symptoms. Further logistic regression showed that illness duration, TSH, TGAb, and TPOAb levels were correlates of glucose disturbances in MDD patients with anxiety. LIMITATIONS: No causal relationship could be drawn due to the cross-sectional design. CONCLUSIONS: Our findings suggest that TSH, TGAb and TPOAb may be promising biomarkers of glucose disturbances in MDD comorbid with anxiety, suggesting the importance of regular assessment of thyroid function parameters for abnormal glucose metabolism prevention.

Inter-relationships of insomnia and psychiatric symptoms with suicidal ideation among patients with chronic schizophrenia: A network perspective.

BACKGROUND: Insomnia is common in patients with schizophrenia, which contributes to worsening psychiatric symptoms and suicidality. We aimed to assess the inter-relationships of insomnia and psychopathology with suicidal ideation (SI) among 1407 Chinese patients with chronic schizophrenia via the network approach. METHOD: We used Positive and Negative Syndrome Scale, Insomnia Severity Index, and Beck Scale for Suicidal Ideation to assess psychiatric symptoms, insomnia, and SI, respectively. Lifetime suicidal attempts (SA) were collected. RESULTS: (1) The incidence of insomnia, lifetime SI, lifetime SA, and current SI was 13.5% (n = 190), 22.8% (n = 321), 13.5% (n = 190), and 9.7% (n = 136), respectively. (2) Patients with insomnia had worse clinical symptoms and higher suicidal risk. (3) Daytime dysfunction, sleep-related distress, conceptual disorganization, delusions, anxiety, and poor rapport were the core symptoms, while late sleep onset and sleep dissatisfaction emerged as bridge symptoms connecting insomnia and psychopathology. (4) Depressive mood, hallucinations, poor impulse control, guilty feelings, insomnia-related impaired quality of life, and sleep dissatisfaction were directly associated with SI. CONCLUSION: Our findings called for formal assessment of insomnia in patients with schizophrenia, which should cover both nocturnal and daytime insomnia symptoms. Targeted interventions for key symptoms may help reduce insomnia, psychiatric symptoms, and SI in patients with schizophrenia.

Efficacy and safety of zuranolone for the treatment of depression: A systematic review and meta-analysis.

Major depressive disorder (MDD) and postpartum depression (PPD) are common and burdensome conditions. This study aims to evaluate the efficacy and safety of zuranolone, a neuroactive steroid γ-aminobutyric acid type A receptors-positive allosteric modulator, in treating MDD and PPD. A comprehensive literature search was conducted until September 2023, identifying seven randomized controlled trials (RCTs). The results demonstrated that zuranolone significantly decreased Hamilton Rating Scale for Depression (HAM-D) scores in patients with PPD or MDD at day 15 (concluding the 14-day course) and day 42-45 (4 weeks after treatment cessation) compared with the placebo, albeit exhibiting a diminishing trend. Moreover, a higher percentage of patients with PPD or MDD achieved HAM-D response and remission with zuranolone treatment compared with placebo at day 15. However, zuranolone did not significantly increase the proportion of MDD patients achieving HAM-D remission at 42/43 days. Adverse events (AEs) such as somnolence, dizziness, and sedation were linked to zuranolone, with a higher but not statistically significant rate of discontinuation due to AEs in the zuranolone group. Overall, our findings support the rapid antidepressant effects of zuranolone in MDD and PPD, along with a relatively favorable safety and tolerability. Large-scale longitudinal RCTs are needed to evaluate the long-term efficacy of zuranolone.

The Mediating Effects of Perceived Family Support in the Relationship Between Anxiety and Problematic Smartphone Use: A Cross-Cultural Validation.

ABSTRACT: Problematic smartphone use (PSU) is frequently considered a public health issue, especially in East Asia and Europe. Yet, there is a paucity of research focusing on cultural and familial determinants of PSU. This cross-cultural study aimed to investigate smartphone usage patterns and possible mediating effects of perceived family support (PFS) from a stress-coping perspective. Convenience samples of 790 Chinese and 439 Belgian undergraduates completed an online survey that focused on sociodemographics and psychological variables ( i.e. , anxiety, depression, PFS, and PSU). In both samples, PSU was positively associated with anxiety and depression, and negatively associated with PFS. However, after controlling for sex and age in structural equation models, the consistent mediating effects of PFS were only found between anxiety and PSU in both cultural settings. These findings suggest that psychological interventions that take into account familial factors could be helpful for young people presenting with anxiety and PSU.

Association of subclinical hypothyroidism with metabolic syndrome and its components among outpatients with first-episode drug-naïve major depressive disorder: a large-scale cross-sectional study.

Both metabolic syndrome (MetS) and subclinical hypothyroidism (SCH) are prevalent in major depressive disorder (MDD) patients. However, their relationship in this population remains unknown. The study assessed the association between SCH and MetS in 1706 first-episode drug-naïve (FEDN) MDD patients. We also compared the relationship between MetS and clinical symptoms in patients with and without comorbid SCH. The Positive and Negative Syndrome Scale positive subscale, the Hamilton Anxiety Rating Scale, and the Hamilton Depression Rating Scale were used to detect clinical symptoms. Serum levels of free triiodothyronine, free thyroxine, thyroid stimulating hormone (TSH), anti-thyroglobulin, thyroid peroxidases antibody, cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and fasting glucose were measured. The Area Under the Curve (AUC) was used to test the performance of serum TSH in identifying MetS patients. The prevalence of MetS and SCH was 34.5% (n = 585) and 61% (n = 1034), respectively. The presence of SCH increased the risk of MetS, hyperglycemia, hypertension, obesity, and low HDL-C by 4.91, 3.51, 3.54, 2.02, and 2.34 times, respectively. Serum TSH had a nice ability to distinguish MetS patients from non-MetS patients (AUC value = 0.77). MetS and its components exhibited a positive association with clinical profiles only in SCH patients, but not in non-SCH patients. Taken together, our study suggested SCH was closely related to MetS and might play a vital role in the relationship between MetS and clinical symptoms. Regular thyroid function checks might help early detect MetS.

Workplace violence inflicted by patients or their family members/visitors and its relationship with suicidal ideation among undergraduate medical students during clinical training in China.

BACKGROUND: Workplace violence in healthcare settings is a significant public concern that profoundly impacts healthcare workers. However, there is a dearth of knowledge regarding the prevalence of workplace violence and its correlation with suicidal ideation among undergraduate medical students in China during their clinical training. The objective of this study was to evaluate the prevalence of workplace violence inflicted by patients or their family members/visitors and to assess its association with suicidal ideation among undergraduate medical students. METHOD: The snowballing sampling technique was used to recruit Chinese medical students. A question designed by the research team was used to ask medical students about their encounters with workplace violence. Students' basic demographic information and mental distresses (learning burnout, depression symptoms, anxiety symptoms, alcohol abuse/dependence, excessive daytime sleepiness and history of mental disorders) were also assessed. As appropriate, the data were analysed using descriptive statistics, chi-square tests, independent-sample t-tests and multiple logistic regression. RESULTS: Out of the 1402 undergraduate medical students who participated, 493 (35.2%) reported having experienced workplace violence inflicted by patients or their family members/visitors, of which 394 (28.1%) were verbal abuse, 14 (1.0%) were physical aggression, and 85 (6.1%) were suffered from both verbal abuse and physical aggression. Furthermore, students exposed to workplace violence were more likely to report suicidal ideation and had a higher prevalence of learning burnout, depression symptoms, anxiety symptoms, alcohol abuse/dependence and excessive daytime sleepiness. Depression symptoms, history of mental disorders, learning burnout and having a partner were significantly associated with suicidal ideation in this population. CONCLUSION: The prevalence of workplace violence inflicted by patients or their family members/visitors was high among undergraduate medical students in China. This may be associated with their mental distress and suicidal ideation. Consequently, it is crucial to strengthen workplace safety measures and promptly implement interventions to mitigate the potentially serious consequences.

Workplace violence was common among Chinese undergraduate medical students during clinical training and may be associated with suicidal ideation, learning burnout, depression symptoms, anxiety symptoms, alcohol abuse/dependence and excessive daytime sleepiness.Depression symptoms, history of mental disorders, learning burnout and having a partner were significantly associated with suicidal ideation among undergraduate medical students exposed to workplace violence.

Positive association between increased homocysteine and deficit syndrome in Chinese patients with chronic schizophrenia: a large-scale cross-sectional study.

Emerging studies indicate that oxidative stress may contribute to deficit syndrome (DS) in patients with schizophrenia. Homocysteine (Hcy) is a well-known marker and mediator of oxidative stress that exhibits tight associations with schizophrenia. However, no previous studies have assessed the relationship of DS with Hcy. This study evaluated the prevalence, clinical characteristics, and association of DS with Hcy in 491 patients with schizophrenia. Plasma levels of Hcy and other metabolic parameters were measured. Positive and Negative Syndrome Scale and the proxy scale for deficit syndrome were employed to assess psychiatric symptoms and DS. The logistic regression model was conducted to assess independent factors associated with DS, and the Area Under the Curve (AUC) was used to assess the performance of our model. There was a high incidence of hyperhomocysteinemia (58.8%) and DS (24.4%). Plasma Hcy levels were significantly higher in patients with DS. Age, Hcy levels, and psychiatric symptoms were independently associated with DS. The combination of these variables perfectly differentiated DS and non-DS patients with an AUC value of 0.89. Our study suggests that elevated Hcy levels may be related to DS. Routine monitoring of Hcy is essential and may facilitate early detection of DS in patients with schizophrenia.

Gender differences in alcohol abuse/dependence among medical undergraduates during the post-COVID­19 pandemic period (October 20, 2020-April 5, 2021) in China.

BACKGROUND: This study aimed to assess the prevalence and the gender-specific risk factors of alcohol abuse/dependence among medical undergraduates during the post-COVID­19 pandemic period in China. METHOD: The Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) was used to identify respondents with alcohol abuse/dependence. A questionnaire on basic demographics and mental distresses (learning burnout, depression symptoms, anxiety symptoms, excessive daytime sleepiness, and history of mental disorders) was used. The logistic regression model was used to explore the associations between the above characteristics and alcohol abuse/dependence. RESULTS: A total of 3,412 medical undergraduates were included in the analysis. Males showed a higher prevalence of alcohol abuse/dependence than females (16.6% vs 7.4%, p < 0.001). Alcohol abuse/dependence was associated with learning burnout (OR: 2.168, p < 0.001) and having a partner (OR: 1.788 p = 0.001) among female medical undergraduates. Among male medical undergraduates, excessive daytime sleepiness (OR: 1.788 p = 0.001) and older age (OR: 1.788, p = 0.001) were independently associated with alcohol abuse/dependence. CONCLUSION: Alcohol abuse/dependence was common among medical undergraduates during the post-COVID­19 pandemic period. Substantial gender differences in the prevalence and risk factors of alcohol abuse/dependence were found among medical undergraduates in this study, which highlighted the need for timely gender-specific screening and interventions. However, the cross-sectional design adopted in this study has limited the examination of causality, thus further longitudinal studies are warranted.

Effects of Multiple High-Dose Methamphetamine Administration on Enteric Dopaminergic Neurons and Intestinal Motility in the Rat Model.

Several studies have identified the effects of methamphetamine (MA) on central dopaminergic neurons, but its effects on enteric dopaminergic neurons (EDNs) are unclear. The aim of this study was to investigate the effects of MA on EDNs and intestinal motility. Male Sprague-Dawley rats were randomly divided into MA group and saline group. The MA group received the multiple high-dose MA treatment paradigm, while the controls received the same saline treatment. After enteric motility was assessed, different intestinal segments (i.e., duodenum, jejunum, ileum, and colon) were taken for histopathological, molecular biological, and immunological analysis. The EDNs were assessed by measuring the expression of two dopaminergic neuronal markers, dopamine transporter (DAT) and tyrosine hydroxylase (TH), at the transcriptional and protein levels. We also used c-Fos protein, a marker of neural activity, to detect the activation of EDNs. MA resulted in a significant reduction in TH and DAT mRNA expression as well as in the number of EDNs in the duodenum and jejunum (p < 0.05). MA caused a dramatic increase in c-Fos expression of EDNs in the ileum (p < 0.001). The positional variability of MA effects on EDNs paralleled the positional variability of its effect on intestinal motility, as evidenced by the marked inhibitory effect of MA on small intestinal motility (p < 0.0001). This study found significant effects of MA on EDNs with locational variability, which might be relevant to locational variability in the potential effects of MA on intestinal functions, such as motility.

Alexithymia in Chinese patients with chronic schizophrenia: Prevalence, clinical correlates, and relationship with neurocognition and empathy.

INTRODUCTION: Alexithymia is highly prevalent and strongly related to adverse consequences in patients with schizophrenia. However, its associated factors remain largely unexplored. The present study aimed to determine the prevalence of alexithymia and its association with sociocultural characteristics, clinical symptoms, neurocognition, and empathy in 854 Chinese patients with schizophrenia. METHOD: Demographic information was collected through a self-designed questionnaire. Alexithymia was assessed by the Toronto Alexithymia Scale (TAS-20). We assessed clinical symptoms, neurocognition, and empathy via the following instruments: Positive and Negative Syndrome Scale, Repeatable Battery for the Assessment of Neuropsychological Status, and Interpersonal Reactivity Index. A multiple logistic regression model was conducted to determine the independent correlates of alexithymia. RESULTS: Approximately one-third (n = 277, 32%) of patients with schizophrenia had alexithymia. Patients with alexithymia had significantly more severe negative symptoms, neurocognition, and empathy impairment than patients without alexithymia. Being male, negative symptoms, personal distress, empathic concern, and language functioning were independently associated with alexithymia. DISCUSSION: Our findings demonstrate a high prevalence of alexithymia and its strong association with clinical symptoms, neurocognition, and empathy, which calls for timely screening and intervention for alexithymia in patients with schizophrenia. Targeting impaired language function, negative symptoms, and impaired affective empathy might help reduce alexithymia and its related negative consequences.

A network analysis of the long-term quality of life and mental distress of COVID-19 survivors 1 year after hospital discharge.

Objectives: COVID-19 survivors suffer from persistent mental distress and impaired quality of life (QOL) after recovery from the infection. However, the symptom-symptom interaction between these psychological variables remained unexplored. The present study aimed to determine the symptom network of mental distress (depression, anxiety, sleep disturbance, fatigue, and post-traumatic stress disorder) and their association with QOL among 535 COVID-19 survivors 1 year after hospital discharge. Methods: 9-item Patient Health Questionnaire, 7-item Generalized Anxiety Disorder Scale, Chalder fatigue scale, Impact of Event Scale-Revised, Pittsburgh Sleep Quality Index, and 36-Item Short-Form Health Survey were applied to measure depression, anxiety, fatigue, PTSD, sleep disturbances, and QOL, respectively. Two networks were estimated using Gaussian graphical model. Network 1 consisted of mental symptoms to determine the central and bridge symptoms. Network 2 additionally included QOL to determine which mental symptoms were mostly related to QOL. Results: 60% of the COVID-19 survivors experienced mental distress 1 year after hospital discharge. Uncontrollable and excessive worry, psychomotor symptoms, intrusion, and daytime dysfunction were the most central symptoms. Daytime dysfunction and fatigue (especially mental fatigue and loss of energy) served as the bridge symptoms across the mental distress network and exhibited the most substantial association with QOL. Conclusion: Our study demonstrated several key symptoms that played a vital role in mental distress and QOL among COVID-19 survivors. Prompt screening and targeted interventions for these symptoms might hold great promise in preventing mental distress and improving QOL in COVID-19 survivors.

Stigmatizing attitudes toward mental illness among caregivers of patients with mental disorders in China.

Objective: This study aimed to investigate stigmatizing attitudes toward depression, schizophrenia, and general anxiety disorder (GAD) among caregivers of patients with mental disorders in China. Methods: A cross-sectional study was conducted among 607 caregivers in China, using vignettes that described three mental illnesses. Data on the caregivers' attitudes and other people's attitudes toward individuals with mental disorders and their willingness to come in contact with people with mental disorders were collected. Results: In the three vignettes, caregivers agreed that positive outcomes outnumbered negative outcomes. The top two statements endorsing the stigma were "the person could snap out of the problem" and "people with this problem are dangerous." In the section for perceived stigma, caregivers in the GAD vignette agreed that most people believed this problem is not a real medical illness, compared to schizophrenia. The rates of the statement endorsing unpredictability were significantly different in the schizophrenia (57.2%) and depression (45.5%) vignette, in comparison to the GAD (45.6%) vignette. For personal stigma, the caregivers tended to avoid people described in the depression vignette more often than in the GAD vignette. The caregivers were most unwilling to let the person described in the vignettes marry into their family, especially in the schizophrenia vignette. Conclusion: Despite the stigma and desire for social distance associated with schizophrenia, depression, and GAD, caregivers often expect positive outcomes. Actions should be taken to improve caregivers' knowledge about mental health and reduce the stigma.