Metabolic and functional substrates of impulsive decision-making in individuals with heroin addiction after prolonged methadone maintenance treatment.

Elevated impulsivity has been frequently reported in individuals with opioid addiction receiving methadone maintenance therapy (MMT), but the underlying neural mechanisms and cognitive subprocesses are not fully understood. We acquired functional magnetic resonance imaging (fMRI) data from 37 subjects with heroin addiction receiving long-term MMT and 33 healthy controls who performed a probabilistic reversal learning task, and measured their resting-state brain glucose using fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Subjects receiving MMT exhibited significantly elevated self-reported impulsivity, and computational modeling revealed a marked impulsive decision bias manifested as switching more frequently without available evidence. Moreover, this impulsive decision bias was associated with the dose and duration of methadone use, irrelevant to the duration of heroin use. During the task, the switch-related hypoactivation in the left rostral middle frontal gyrus was correlated with the impulsive decision bias while the function of reward sensitivity was intact in subjects receiving MMT. Using prior brain-wide receptor density data, we found that the highest variance of regional metabolic abnormalities was explained by the spatial distribution of µ-opioid receptors among 10 types of neurotransmitter receptors. Heightened impulsivity in individuals receiving prolonged MMT is manifested as atypical choice bias and noise in decision-making processes, which is further driven by deficits in top-down cognitive control, other than reward sensitivity. Our findings uncover multifaceted mechanisms underlying elevated impulsivity in subjects receiving MMT, which might provide insights for developing complementary therapies to improve retention during MMT.

An exploratory cross-sectional study on the impact of education on perception of stigma by Chinese patients with schizophrenia.

BACKGROUND: Stigma is a major issue across various society and cultures, and few studies focus on the perception of stigma by Chinese patients with schizophrenia. In the current cross-sectional study, we sought to assess the extent of internalized stigma among outpatients with schizophrenia in China and to investigate whether education level correlated with the experience of stigma. METHODS: Outpatients with schizophrenia were evaluated using the brief psychosis rating scale (BPRS), the positive and negative syndrome scale (PANSS), the clinical global impression-severity of illness (CGI-SI) scale and the Stigma Scale for Mental Illness (SSMI 2C). Patients were categorized into the high education and low education group according to their educational levels. RESULTS: One hundred thirty-three subjects were included in the study. Their mean course of illness was 4.32 ± 6.14 years (range, 1 month to 15 years). Their mean BPRS score was 19.87 ± 5.46, their mean PANSS score was 44.11 ± 13.1, and their mean CGI-SI score was 2.22 ± 0.81. In addition, the mean SSMI 2C score of the high education group (7.15 ± 0.98) was markedly higher than that of the low education group (5.75 ± 0.79, P < 0.05). The mean domain I score of the high education group (2.30 ± 0.76) was comparable to that of the low education group (2.07 ± 0.78, P > 0.05). The mean domain II score of the high education group (2.42 ± 0.96) was markedly higher than that of the low education group (2.01 ± 0.79, P < 0.05). Moreover, the mean domain III score of the high education group (2.43 ± 0.79) was significantly higher than that of the low education group (1.67 ± 0.77, P < 0.05). CONCLUSIONS: Education level impacts on the perception of stigma by patients with schizophrenia and more psycho-education should be done to improve patients' knowledge about schizophrenia.

Quantitative Expression of Latent Disease Factors in Individuals Associated with Psychopathology Dimensions and Treatment Response.

Psychiatric comorbidity is common in symptom-based diagnoses like autism spectrum disorder (ASD), attention/deficit hyper-activity disorder (ADHD), and obsessive-compulsive disorder (OCD). However, these co-occurring symptoms mediated by shared and/or distinct neural mechanisms are difficult to profile at the individual level. Capitalizing on unsupervised machine learning with a hierarchical Bayesian framework, we derived latent disease factors from resting-state functional connectivity data in a hybrid cohort of ASD and ADHD and delineated individual associations with dimensional symptoms based on canonical correlation analysis. Models based on the same factors generalized to previously unseen individuals in a subclinical cohort and one local OCD database with a subset of patients undergoing neurosurgical intervention. Four factors, identified as variably co-expressed in each patient, were significantly correlated with distinct symptom domains (r = -0.26-0.53, P < 0.05): behavioral regulation (Factor-1), communication (Factor-2), anxiety (Factor-3), adaptive behaviors (Factor-4). Moreover, we demonstrated Factor-1 expressed in patients with OCD and Factor-3 expressed in participants with anxiety, at the degree to which factor expression was significantly predictive of individual symptom scores (r = 0.18-0.5, P < 0.01). Importantly, peri-intervention changes in Factor-1 of OCD were associated with variable treatment outcomes (r = 0.39, P < 0.05). Our results indicate that these data-derived latent disease factors quantify individual factor expression to inform dimensional symptom and treatment outcomes across cohorts, which may promote quantitative psychiatric diagnosis and personalized intervention.

[Selective serotonin reuptake inhibitor is more likely to induce sexual dysfunction than mirtazapine in treating depression].

OBJECTIVE: To compare the incidences of sexual dysfunction induced by mirtazapine and SSRI in the treatment of patients with depression. METHODS: Using key-word retrieval from the compact disks of the Chinese biological medicine (CBM) data base, we analyzed the rates of sexual dysfunction from the published clinical control trials on depression treated with mirtazapine and SSRI by applying the fixed effects model (FEM) of evidence-based medicine (EBM). RESULTS: Among 1108 cases in 14 studies, there were 5 cases of mirtazapine-induced and 106 cases of SSRI-induced sexual dysfunction, accounting for 0.90% and 19.2% respectively, OR = 0.07 (95% CI: 0.04-0.14), Z = 8.03, P < 0.01. CONCLUSION: SSRI is far more likely to induce sexual dysfunction than mirtazapine in the treatment of depression.

A cross-sectional study on perception of stigma by Chinese schizophrenia patients.

OBJECTIVE: In this cross-sectional study, we sought to assess the extent of internalized stigma among inpatients and outpatients with schizophrenia in the People's Republic of China and to investigate whether education level correlated with the experience of stigma. METHODS: Schizophrenia patients were evaluated using the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions-Severity of Illness (CGI-S) scale and the Stigma Scale for Mental Illness (SSMI-C). Patients were categorized into high education and low education groups, according to their educational levels. RESULTS: One hundred thirty-three subjects were included in the study. Their mean course of illness was 4.32±6.14 years (range: 1 month to 15 years). Their mean BPRS score was 19.87±5.46, their mean PANSS score was 44.11±13.1, and their mean CGI-S score was 2.22±0.81. In addition, their mean SSMI-C score was 6.49±0.9. The mean SSMI-C score of patients who have received high school education or above was 7.15±0.98, which was markedly higher than that of patients who have received middle school education or below, which was 5.75±0.79 (P<0.05). Before the study most patients (92.5%, 123/133) took atypical drugs. CONCLUSION: Education level impacts on the perception of stigma by schizophrenia patients, and more psychoeducation should be undertaken to improve patients' knowledge about schizophrenia.