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Objective@#The cerebello-thalamic tract is the only efferent white matter (WM) bundle of the cerebellum that connects the cerebellum to the thalamus and has recently attracted much attention in obsessive-compulsive disorder (OCD) with its integral role in higher order cognitive functions commonly impaired in OCD patients. Previous neuroimaging studies have shown that the cerebello-thalamic circuit is functionally impaired in OCD patients. However, the WM integrity of the cerebello-thalamic tract in OCD, which may underly functional abnormalities of the cerebello-thalamic circuit, is not yet sufficiently understood. Therefore, the current study aimed to elucidate whether compromised cerebello-thalamic WM integrity is observed in medication-free OCD patients. @*Methods@#In this study, diffusion tensor imaging was acquired from 106 medication-free OCD patients and 105 matched healthy controls (HCs). Probabilistic tractography was then used to reconstruct the cerebello-thalamic tract with accurate anatomical features. Three diffusion indices (fractional anisotropy, FA; mean diffusivity, MD; radial diffusivity, RD) were measured from the reconstructed bilateral cerebello-thalamic tract and then compared between groups. @*Results@#We found that patients with OCD showed significantly increased MD and RD in the right cerebello-thalamic tract compared to HCs, and there was no difference in FA between groups. @*Conclusion@#Our findings may indicate the underlying structural abnormalities of the dysfunctional cerebello-thalamic circuit in OCD patients. Therefore, our findings are expected to provide novel insights into the pathophysiology of OCD on the cerebello-thalamic WM architecture, extending our knowledge from the existing functional neurobiological model of OCD.
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Objective@#In the triple-network model, the salience network (SN) plays a crucial role in switching between the default-mode network (DMN) and the central executive network (CEN). Aberrant patterns of triple-network connectivity have been reported in schizophrenia patients, while findings have been less consistent for patients in the early stages of psychotic disorders. Thus, the present study examined the connectivity among the SN, DMN, and CEN in first-episode psychosis (FEP) patients and individuals at clinical high risk (CHR) for psychosis. @*Methods@#Thirty-nine patients with FEP, 78 patients with CHR for psychosis, and 110 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging. We compared the SN, DMN, and CEN connectivity patterns of the three groups. The role of the SN in networks with significant connectivity differences was examined by mediation analysis. @*Results@#FEP patients showed lower SN-DMN and SN-CEN (cluster-level F=5.83, false discovery rate [FDR] corrected-p=0.001) connectivity than HCs. There was lower SN-DMN connectivity (cluster-level F=3.06, FDR corrected-p=0.053) at a trend level in CHR subjects compared to HCs. Between HCs and FEP patients, mediation analysis showed that SN-DMN connectivity was a mediator between group and SN-CEN connectivity. Additionally, SN-CEN connectivity functioned as a mediator between group and SN-DMN connectivity. @*Conclusion@#Aberrant connectivity between the SN and DMN/CEN suggests disrupted network switching in FEP patients, although CHR subjects showed trend-level SN-DMN dysconnectivity. Our findings suggest that dysfunctional triple-network dynamics centered on the SN can appear in patients in the early stages of psychotic disorders.
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Objective@#Striatal dopamine dysfunction caused by cortical abnormalities is a leading hypothesis of schizophrenia. Although prefrontal cortical pathology is negatively correlated with striatal dopamine synthesis, the relationship between structural frontostriatal connectivity and striatal dopamine synthesis has not been proved in patients with schizophrenia with different treatment response. We therefore investigated the relationship between frontostriatal connectivity and striatal dopamine synthesis in treatment-responsive schizophrenia (non-TRS) and compared them to treatment-resistant schizophrenia (TRS) and healthy controls (HC). @*Methods@#Twenty-four patients with schizophrenia and twelve HC underwent [18F] DOPA PET scans to measure dopamine synthesis capacity (the influx rate constant Kicer) and diffusion 3T MRI to measure structural connectivity (fractional anisotropy, FA). Connectivity was assessed in 2 major frontostriatal tracts. Associations between Kicer and FA in each group were evaluated using Spearman’s rho correlation coefficients. @*Results@#Non-TRS showed a negative correlation (r=-0.629, p=0.028) between connectivity of dorsolateral prefrontal cortex-associative striatum (DLPFC-AST) and dopamine synthesis capacity of associative striatum but this was not evident in TRS (r=-0.07, p=0.829) and HC (r=-0.277, p=0.384). @*Conclusion@#Our findings are consistent with the hypothesis of dysregulation of the striatal dopaminergic system being related to prefrontal cortex pathology localized to connectivity of DLPFC-AST in non-TRS, and also extend the hypothesis to suggest that different mechanisms underlie the pathophysiology of non-TRS and TRS.
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Objective@#Electroconvulsive therapy (ECT) has been the most potent treatment option for treatment-resistant schizophrenia (TRS). However, the underlying neural mechanisms of ECT in schizophrenia remain largely unclear. This paper examines studies that investigated structural and functional changes after ECT in patients with schizophrenia. @*Methods@#We carried out a systematic review with following terms: ‘ECT’, ‘schizophrenia’, and the terms of various neuroimaging modalities. @*Results@#Among the 325 records available from the initial search in May 2020, 17 studies were included. Cerebral blood flow in the frontal, temporal, and striatal structures was shown to be modulated (n=3), although the results were divergent. Magnetic resonance spectroscopy (MRS) studies suggested that the ratio of N-acetyl-aspartate/creatinine was increased in the left prefrontal cortex (PFC; n=2) and left thalamus (n=1). The hippocampus and insula (n=6, respectively) were the most common regions of structural/functional modulation, which also showed symptom associations. Functional connectivity of the default mode network (DMN; n=5), PFC (n=4), and thalamostriatal system (n=2) were also commonly modulated. @*Conclusion@#Despite proven effectiveness, there has been a dearth of studies investigating the neurobiological mechanisms underlying ECT. There is preliminary evidence of structural and functional modulation of the hippocampus and insula, functional changes in the DMN, PFC, and thalamostriatal system after ECT in patients with schizophrenia. We discuss the rationale and implications of these findings and the potential mechanism of action of ECT. More studies evaluating the mechanisms of ECT are needed, which could provide a unique window into what leads to treatment response in the otherwise refractory TRS population.
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Objectives@#Clozapine is the most effective atypical antipsychotic agent for the treatment-resistant schizophrenia (TRS), however, only 40%–70% of TRS patients respond to clozapine. Moreover, TRS encompasses various symptom dimensions. Therefore, augmentation with other medications for clozapine is frequently applied. However, the prescription pattern of clozapine and combined medications in Korea is yet to be examined. This study aims to investigate the maintenance treatment pattern of clozapine and augmentation agents in one Korean tertiary hospital. @*Methods@#The patients with schizophrenia spectrum disorders under clozapine maintenance, defined as one-year clozapine continuation, were subjected for analysis. Medication data at one-year time-point after clozapine initiation was extracted and analyzed. @*Results@#Among total 2897 patients having clozapine prescription experience from January 2000 to December 2018, 1011 patients were on clozapine maintenance. The mean age of clozapine initiation was 30.2 ± 11.3 years, and the maintenance dose of clozapine was 217.8 ± 124.3 mg/day. Combination rate of antipsychotics, mood stabilizers, and antidepressants were 43.5%, 25.3%, 38.6%, respectively. Most frequently prescribed drugs in each category were aripiprazole, valproate, and sertraline. Olanzapine equivalent dose of combined antipsychotics was 10.4 ± 7.7 mg/day. Male patients were prescribed higher dose of combined antipsychotics and higher rate of antidepressants. Female patients had later onset of clozapine prescription. Patients with two or more combined antipsychotics were prescribed higher dose of clozapine and higher rate of antidepressants compared to patients with one combined antipsychotic. @*Conclusions@#Taken together, among the patients taking clozapine, a substantial rate of patients were under polypharmacy. The present findings based on the real-world prescription pattern could provide the valuable clinical information on the treatment of TRSrelated conditions.
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Objectives@#Although the characteristics of different aggression subtypes provide important information in establishing treatment and prevention strategies in schizophrenia patients, limited information is available about the characteristics of the aggressive subtype in schizophrenia patients in South Korea. The present study was designed to compare the demographic and psychological characteristics across the impulsive and premeditated aggression subtypes in schizophrenia patients in South Korea who had committed a crime. @*Methods@#We enrolled 116 schizophrenia spectrum disorder patients who were admitted to the National Forensic Psychiatric Hospital. Using the criminal and interview records, the study subjects were divided into 83 impulsive and 33 premeditated aggression groups. The subjects’ demographic and psychological characteristics were summarized and compared across aggression subtypes. @*Results@#Compared to the premeditated aggression group, the impulsive aggression group had a higher intelligent quotient and a lower rate of physical and sexual abuse experience. @*Conclusion@#To our knowledge, this is the first study to describe the characteristics of aggression subtypes in schizophrenia patients in South Korea who had committed a crime. Our results suggest that different treatment and prevention strategies should be considered for each aggression subtype.
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Objective@#Electroconvulsive therapy (ECT) has been the most potent treatment option for treatment-resistant schizophrenia (TRS). However, the underlying neural mechanisms of ECT in schizophrenia remain largely unclear. This paper examines studies that investigated structural and functional changes after ECT in patients with schizophrenia. @*Methods@#We carried out a systematic review with following terms: ‘ECT’, ‘schizophrenia’, and the terms of various neuroimaging modalities. @*Results@#Among the 325 records available from the initial search in May 2020, 17 studies were included. Cerebral blood flow in the frontal, temporal, and striatal structures was shown to be modulated (n=3), although the results were divergent. Magnetic resonance spectroscopy (MRS) studies suggested that the ratio of N-acetyl-aspartate/creatinine was increased in the left prefrontal cortex (PFC; n=2) and left thalamus (n=1). The hippocampus and insula (n=6, respectively) were the most common regions of structural/functional modulation, which also showed symptom associations. Functional connectivity of the default mode network (DMN; n=5), PFC (n=4), and thalamostriatal system (n=2) were also commonly modulated. @*Conclusion@#Despite proven effectiveness, there has been a dearth of studies investigating the neurobiological mechanisms underlying ECT. There is preliminary evidence of structural and functional modulation of the hippocampus and insula, functional changes in the DMN, PFC, and thalamostriatal system after ECT in patients with schizophrenia. We discuss the rationale and implications of these findings and the potential mechanism of action of ECT. More studies evaluating the mechanisms of ECT are needed, which could provide a unique window into what leads to treatment response in the otherwise refractory TRS population.
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Objectives@#Although the characteristics of different aggression subtypes provide important information in establishing treatment and prevention strategies in schizophrenia patients, limited information is available about the characteristics of the aggressive subtype in schizophrenia patients in South Korea. The present study was designed to compare the demographic and psychological characteristics across the impulsive and premeditated aggression subtypes in schizophrenia patients in South Korea who had committed a crime. @*Methods@#We enrolled 116 schizophrenia spectrum disorder patients who were admitted to the National Forensic Psychiatric Hospital. Using the criminal and interview records, the study subjects were divided into 83 impulsive and 33 premeditated aggression groups. The subjects’ demographic and psychological characteristics were summarized and compared across aggression subtypes. @*Results@#Compared to the premeditated aggression group, the impulsive aggression group had a higher intelligent quotient and a lower rate of physical and sexual abuse experience. @*Conclusion@#To our knowledge, this is the first study to describe the characteristics of aggression subtypes in schizophrenia patients in South Korea who had committed a crime. Our results suggest that different treatment and prevention strategies should be considered for each aggression subtype.
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Objective@#Although previous studies have reported impaired performance in the reading the mind in the eyes test (RMET), which measures complex emotion recognition abilities, in patients with schizophrenia, reports regarding individuals at clinical high risk (CHR) for psychosis have been inconsistent, mainly due to the interacting confounding effects of general cognitive abilities and age. We compared RMET performances across first-episode psychosis (FEP) patients, CHR individuals, and healthy controls (HCs) while controlling for the effects of both general cognitive abilities and age. @*Methods@#A total of 25 FEP, 41 CHR, and 44 HC subjects matched for age participated in this study. RMET performance scores were compared across the groups using analysis of variance with sex and intelligence quotient as covariates. Exploratory Pearson’s correlation analyses were performed to reveal the potential relationships of RMET scores with clinical symptom severity in the FEP and CHR groups. @*Results@#RMET performance scores were significantly lower among FEP and CHR participants than among HCs. FEP patients and CHR subjects showed comparable RMET performance scores. RMET scores were negatively correlated with Positive and Negative Syndrome Scale (PANSS) positive symptom subscale scores in the FEP patients. No significant correlation was identified between RMET scores and other clinical scale scores. @*Conclusion@#Impaired RMET performance is present from the risk stage of psychosis, which might be related to positive symptom severity in early psychosis. Longitudinal studies are necessary to confirm the stability of complex emotion recognition impairments and their relationship with social functioning in early psychosis patients.
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Objective@#It is well established that the cortico-striato-thalamo-cortical (CSTC) circuit is implicated in the pathophysiology of obsessive- compulsive disorder (OCD). However, reports on corticostriatal functional connectivity (FC) in OCD have been inconsistent due to the structural and functional heterogeneity of the striatum. Therefore, in the present study, we investigated corticostriatal FC using a fine 12-seed striatal parcellation to overcome this heterogeneity and discover the neural correlates of symptoms in OCD patients. @*Methods@#We recruited 23 OCD patients and 23 healthy controls (HCs). Whole-brain FC based on striatal seeds was examined using resting-state functional magnetic resonance imaging data and compared across OCD patients and HCs. We conducted correlation analysis between FCs of striatal subregions with significant group differences and symptom severity scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Hamilton Rating Scale for Depression, and Hamilton Rating Scale for Anxiety (HAM-A). @*Results@#Compared to HCs, patients demonstrated increased FC of the dorsal caudal putamen and ventral rostral putamen (VRP) with several cortical regions, such as the intracalcarine cortex, inferior frontal gyrus, supramarginal/angular gyrus (SMG/AG), and postcentral gyrus (PCG). Furthermore, FC between the VRP and SMG/AG and between the VRP and PCG was negatively correlated with scores on the Y-BOCS compulsive subscale and the HAM-A, respectively. @*Conclusion@#These findings suggest that striatal subregions have strengthened FC with extensive cortical regions, which may reflect neural correlates of compulsive and anxious symptoms in OCD patients. These results contribute to an improved understanding of OCD pathophysiology by complementing the current evidence regarding striatal FC.
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Background@#To investigate the effects of a glucagon-like peptide-1 receptor agonist on functional brain activation in lean and obese individuals with type 2 diabetes mellitus (T2DM) in response to visual food cues. @*Methods@#In a randomized, single-blinded, crossover study, 15 lean and 14 obese individuals with T2DM were administered lixisenatide or normal saline subcutaneously with a 1-week washout period. We evaluated brain activation in response to pictures of high-calorie food, low-calorie food, and nonfood using functional magnetic resonance imaging and measured appetite and caloric intake in participants who were given access to an ad libitum buffet. @*Results@#Obese individuals with T2DM showed significantly greater activation of the hypothalamus, pineal gland, parietal cortex (high-calorie food vs. low-calorie food, P<0.05), orbitofrontal cortex (high-calorie food vs. nonfood, P<0.05), and visual cortex (food vs. nonfood, P<0.05) than lean individuals with T2DM. Lixisenatide injection significantly reduced the functional activation of the fusiform gyrus and lateral ventricle in obese individuals with T2DM compared with that in lean individuals with T2DM (nonfood vs. high-calorie food, P<0.05). In addition, in individuals who decreased their caloric intake after lixisenatide injection, there were significant interaction effects between group and treatment in the posterior cingulate, medial frontal cortex (high-calorie food vs. low-calorie food, P<0.05), hypothalamus, orbitofrontal cortex, and temporal lobe (food vs. nonfood, P<0.05). @*Conclusion@#Brain responses to visual food cues were different in lean and obese individuals with T2DM. In addition, acute administration of lixisenatide differentially affected functional brain activation in these individuals, especially in those who decreased their caloric intake after lixisenatide injection.
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Modified electroconvulsive therapy (ECT) which started in 1950s is a safe and efficacious treatment for several mental disorders including mood disorders and psychotic disorders. However, its usage in present days is still limited by misconceptions and stigmata of ECT. This paper overviews the background from which the stigmata of ECT stemmed and the current status of stigmata surrounding ECT among the public and medical professionals. In addition, a few potential strategies for reducing stigmata of ECT are provided in this review.
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Objective@#Although previous studies have reported impaired performance in the reading the mind in the eyes test (RMET), which measures complex emotion recognition abilities, in patients with schizophrenia, reports regarding individuals at clinical high risk (CHR) for psychosis have been inconsistent, mainly due to the interacting confounding effects of general cognitive abilities and age. We compared RMET performances across first-episode psychosis (FEP) patients, CHR individuals, and healthy controls (HCs) while controlling for the effects of both general cognitive abilities and age. @*Methods@#A total of 25 FEP, 41 CHR, and 44 HC subjects matched for age participated in this study. RMET performance scores were compared across the groups using analysis of variance with sex and intelligence quotient as covariates. Exploratory Pearson’s correlation analyses were performed to reveal the potential relationships of RMET scores with clinical symptom severity in the FEP and CHR groups. @*Results@#RMET performance scores were significantly lower among FEP and CHR participants than among HCs. FEP patients and CHR subjects showed comparable RMET performance scores. RMET scores were negatively correlated with Positive and Negative Syndrome Scale (PANSS) positive symptom subscale scores in the FEP patients. No significant correlation was identified between RMET scores and other clinical scale scores. @*Conclusion@#Impaired RMET performance is present from the risk stage of psychosis, which might be related to positive symptom severity in early psychosis. Longitudinal studies are necessary to confirm the stability of complex emotion recognition impairments and their relationship with social functioning in early psychosis patients.
ABSTRACT
Modified electroconvulsive therapy (ECT) which started in 1950s is a safe and efficacious treatment for several mental disorders including mood disorders and psychotic disorders. However, its usage in present days is still limited by misconceptions and stigmata of ECT. This paper overviews the background from which the stigmata of ECT stemmed and the current status of stigmata surrounding ECT among the public and medical professionals. In addition, a few potential strategies for reducing stigmata of ECT are provided in this review.
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OBJECTIVE@#In this study, we examined the reliability and validity of the Korean version of the Prodromal Questionnaire-Brief (PQ-B), a self-report screening instrument for clinical high risk for psychosis (CHR).@*METHODS@#A total of 3,400 middle, high school and college students participated, and 261 subjects with a PQ-B total score ≥3 completed both the PQ-B and the Structured Interview for Prodromal Syndromes (SIPS). Receiver operating characteristic (ROC) curves were used to examine the psychometric properties of the PQ-B.@*RESULTS@#A cut-off of 7 for the PQ-B total score and a cut-off of 22 for the PQ-B distress score showed the best balance of sensitivity (72.2%, 77.8%) and specificity (71.4%, 75.0%).@*CONCLUSION@#The Korean version of the PQ-B showed good reliability and validity for predicting prodromal risk symptoms in the community population.
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BACKGROUND: Because there has been a recent increase in refugee applications in Korea, the mental health of these refugees merits greater study. METHODS: We surveyed 129 refugees (including those in process of refugee application) and 121 migrant workers living in urban communities, using: the Patient Health Questionnaire-9 for depressive symptoms, the Impact Event Scale-Revised for post-traumatic stress disorder (PTSD) symptoms, and the health questionnaires used in 2016 Korean National Health and Nutrition Examination Survey (KNHANES). The majority of refugee subjects were from sub-Saharan Africa and Middle East. We compared the prevalence of possible depression and possible PTSD between refugees and migrant workers and refugees and age-gender matched samples from the KNHANES 2016. RESULTS: Frequency of suicidal planning during the last year was higher in the refugee group than Korean nationals, but frequency of suicidal attempt was not. High risk drinking was found in 0.8% of refugees, 6.6% of migrant workers and 27.2% of Korean nationals. Possible depression was present in 42.9% of refugee subjects, 33.3% of migrant workers, and 4.2% of Korean controls. Possible PTSD was present in 38.9% of refugees compared to 12.5% of migrant workers. Only major risk factor for depression among refugees was a traumatic event before entering Korea. CONCLUSION: Possible depression and PTSD are significantly more prevalent in refugees, compared to both migrant workers and Korean nationals. Prevalence rates are commensurate with refugee studies worldwide. Appropriate early screening and intervention schemes need to be developed for refugees entering Korea.
Subject(s)
Adult , Humans , Africa South of the Sahara , Depression , Drinking , Independent Living , Korea , Mass Screening , Mental Health , Middle East , Nutrition Surveys , Prevalence , Refugees , Risk Factors , Stress Disorders, Post-Traumatic , Transients and MigrantsABSTRACT
OBJECTIVE: Although early intervention from the beginning of a psychotic episode is essential for a better prognosis, biomarkers predictive of symptomatic and functional improvement in early psychotic disorders are lacking. This study aimed to investigate whether the spectral power of resting-state electroencephalography (EEG) can be used as a predictive marker of the 1-year prognosis in patients with first-episode psychosis (FEP). METHODS: Twenty-four patients with FEP and matched healthy control (HC) subjects were examined with resting-state EEG at baseline. The symptomatic severity and functional status of FEP patients were assessed at baseline and reassessed after 1 year of usual treatment. Repeated measures analysis of variance was conducted to compare EEG spectral powers across the groups. Multiple regression analysis revealed EEG spectral powers predictive of symptomatic and functional improvement in FEP patients at the 1-year follow-up. RESULTS: Delta band power in the frontal and posterior regions was significantly higher in patients with FEP than in HCs. Higher delta band power in the posterior region predicted later improvement of positive symptoms and general functional status. Lower delta band power in the frontal region predicted improvement of negative symptoms and general functioning after 1 year. CONCLUSION: These results suggest that increased delta absolute power is observed from the beginning of psychotic disorders. Furthermore, decreased delta power in the frontal region and increased delta power in the posterior region might be used as a predictive marker of a better prognosis of FEP, which would aid early intervention in clinical practice.
Subject(s)
Humans , Biomarkers , Early Intervention, Educational , Electroencephalography , Follow-Up Studies , Polytetrafluoroethylene , Prognosis , Psychotic DisordersABSTRACT
We aim to investigate the effect of fronto-temporal transcranial direct current stimulation (tDCS) on the interactions among functional networks and its association with psychotic symptoms. In this pilot study, we will determine possible candidate functional networks and an adequate sample size for future research. Seven schizophrenia patients with treatment-refractory auditory hallucinations underwent tDCS twice daily for 5 days. Resting-state fMRI data and measures of the severity of psychotic symptoms were acquired at baseline and after completion of the tDCS sessions. At baseline, decreased functional network interaction was negatively correlated with increased hallucinatory behavior. After tDCS, the previously reduced functional network connectivity significantly increased. Our results showed that fronto-temporal tDCS could possibly remediate aberrant hallucination-related functional network interactions in patients with schizophrenia.
Subject(s)
Humans , Hallucinations , Magnetic Resonance Imaging , Neuroimaging , Pilot Projects , Sample Size , Schizophrenia , Transcranial Direct Current StimulationABSTRACT
OBJECTIVES: This study was performed to examine the effects of the public attention to ‘crime of schizophrenia’ on the use of mental health services in patients with schizophrenia using big data analysis. METHODS: Data on the frequency of internet searches for ‘crime of schizophrenia’ and the patterns of mental health service utilization by patients with schizophrenia spectrum disorders by month were collected from Naver big data and the Health Insurance Review and Assessment Services in Korea, respectively. Their correlations in the same and following month for lagged effect were examined. RESULTS: The number of outpatients correlated negatively with public attention to ‘crime of schizophrenia’ in the same month. The lagged relationship between public attention and the number of admissions in psychiatric wards was also found. In terms of sex differences, the use of outpatient services among female patients correlated negatively with public attention in the same month while the number of male patients' admissions in both same and following month correlated positively with public attention. CONCLUSION: These findings suggested that public attention to ‘crime of schizophrenia’ could negatively affect illness behavior in patients with schizophrenia.
Subject(s)
Female , Humans , Male , Crime , Illness Behavior , Insurance, Health , Internet , Korea , Mental Health Services , Mental Health , Outpatients , Schizophrenia , Sex Characteristics , Statistics as TopicABSTRACT
No abstract available.