Design and Methodology of the Korean Early Psychosis Cohort Study

Clinical, cognitive, and functional characteristics of recent-onset psychosis with autistic features: A 2-year longitudinal study

Though categorized as separate illnesses, schizophrenia and autism are known to exhibit shared characteristics. This study explored the distinctions in clinical, cognitive, and functional characteristics among individuals with recent-onset psychosis, considering the severity of their autistic symptoms, involving longitudinal examinations. We analyzed 671 patients with recent-onset psychosis from Korean Early Psychosis Cohort Study (KEPS), and used the PANSS Autism Severity Score (PAUSS) to categorize patient into 'autistic', 'moderate', and 'non-autistic' groups. The autistic group had the highest rate of schizophrenia diagnosis, and the lowest incidence of comorbid psychiatric disorders. Schizophrenia diagnosis predicted membership of the autistic group. More severe autistic symptoms correlated with worse overall symptoms and functional outcomes, which significantly predicted membership of the autistic group. Cognitive impairments and emotional recognition difficulties increased with the severity of autistic symptoms. 2-year longitudinal assessments demonstrated that group differences in autistic features and overall symptoms, and functional outcomes remained consistent, and membership of the autistic group significantly predicted symptomatic remission and functional recovery. In conclusion, the presence of autistic symptoms has a significant impact on the overall symptomatology and functional capabilities. They are enduring attributes rather than temporary state variables, and serve as a significant predictor for both symptomatic and functional recovery.

Network biomarkers in recovered psychosis patients who discontinued antipsychotics

There are no studies investigating topological properties of resting-state fMRI (rs-fMRI) in patients who have recovered from psychosis and discontinued medication (hereafter, recovered patients [RP]). This study aimed to explore topological organization of the functional brain connectome in the RP using graph theory approach. We recruited 30 RP and 50 age and sex-matched healthy controls (HC). The RP were further divided into the subjects who were relapsed after discontinuation of antipsychotics (RP-R) and who maintained recovered state without relapse (RP-M). Using graph-based network analysis of rs-fMRI signals, global and local metrics and hub information were obtained. The robustness of the network was tested with random failure and targeted attack. As an ancillary analysis, Network-Based Statistic (NBS) was performed. Association of significant findings with psychopathology and cognitive functioning was also explored. The RP showed intact network properties in terms of global and local metrics. However, higher global functional connectivity strength and hyperconnectivity in the interconnected component were observed in the RP compared to HC. In the subgroup analysis, the RP-R were found to have lower global efficiency, longer characteristic path length and lower robustness whereas no such abnormalities were identified in the RP-M. Associations of the degree centrality of some hubs with cognitive functioning were identified in the RP-M. Even though network properties of the RP were intact, subgroup analysis revealed more altered topological organizations in the RP-R. The findings in the RP-R and RP-M may serve as network biomarkers for predicting relapse or maintained recovery after the discontinuation of antipsychotics.

Predictors of full recovery in patients with early stage schizophrenia spectrum disorders

To promote recovery in psychosis, targeting modifiable factors related to recovery is critical. Using more strict definition of full recovery, we examined predictors for recovery in patients with early stage schizophrenia spectrum disorders (SSD) followed up to 6.5 years. The target subjects were 375 patients with early stage SSD who had been over at least 1-year after registration and evaluated. The criteria for full recovery were having the score of the Positive and Negative Syndrome Scale (PANSS) 8-item ≤ 2 and adequate functional recovery for at least 1-year. We performed univariate Cox and stepwise Cox regression in both total and acute patients. In stepwise Cox regression, several independent predictors for recovery, i.e., negative symptoms of the PANSS, duration of untreated psychosis (DUP) and non-professional job were identified in patients with early stage SSD. In acute patients, other factors such as professional job and subjective well-being under neuroleptics were more important. The present study identified independent predictors for recovery modifiable by various psychosocial intervention and early intervention services. Moreover, it highlights the need of providing different treatment strategies depending on clinical status.

Comparison of clinical features and 1-year outcomes between patients with psychotic disorder not otherwise specified and those with schizophrenia

AIM

Research on psychotic disorder not otherwise specified (PNOS) that clearly mentions its subgroups is very rare. This study was conducted to identify the demographic and clinical features, cognitive function, and 1-year outcomes of patients with early stage PNOS compared with those with early stage schizophrenia (SZ).

METHODS

The study subjects were 54 and 321 patients with PNOS and SZ, respectively, who were registered at least more than 1 year ago. Due to drop out, only 37 and 210 patients with PNOS and SZ were evaluated at the 1-year follow-up. We compared clinical variables (duration of untreated psychosis, symptom severity, self-rating scales, and so on), cognitive function, and short-term outcomes (treatment response, remission, compliance, drop out, relapse) between the two groups.

RESULTS

The patients with PNOS were associated with higher diagnostic stability (53.7%) compared with those in previous studies. They had lower symptom severity, better treatment response at 2 months and higher remission rates at 12 months, but poorer compliance at 6 months compared with patients with SZ. Level of cognitive impairment in PNOS was intermediate between those of SZ patients and healthy controls.

CONCLUSIONS

These findings indicate that PNOS has unique clinical features, suggesting that it should be treated as a distinct clinical syndrome. At the same time, however, prevention of its possible progression to other psychotic disorders in some patients with PNOS is also important.

Three-year outcomes and predictors for full recovery in patients with early-stage psychosis

In the present study, various outcomes over 3-year period in patients with early stage psychosis including remission, recovery, relapse and medication adherence were investigated. Predictor for full recovery at year 3 was also examined. Three-year follow-up data in 534 patients with schizophrenia spectrum disorders (SSD) and psychotic disorder not otherwise specified (PNOS) were examined for overall outcome trajectories. The data of completers at year 3 (n = 157) were used to identify predictors for recovery using logistic regression. The rates of symptomatic remission and full recovery at 6-, 12-, 24-, and 36-month follow-up were 76.10, 69.20, 79.50, and 79.10%, and 22.80, 26.40, 28.60, and 39.60%, respectively. The rates of drop-out and relapse at 6-, 12-, 24-, and 36-month follow-up were 25.4, 29.5, 38.6, and 51.1%, and 3.7, 8.9, 19.0, and 38.9%, respectively. The rates of good adherence and prescription of Long-Acting Injectable Antipsychotics (LAIA) at 6-, 12-, 24- and 36-month follow-up were 87.8, 88.0, 91.9, and 93.9%, and 18.3, 21.7, 22.0, and 25.5%, respectively. Significant predictors for full recovery were duration of untreated psychosis (DUP), family intimacy and physical activity. We observed similar or better results on remission, recovery, and relapse rates compared to other previous studies. Effective psychosocial intervention should be provided to shorten the gap between remission and recovery rates and to address DUP, family issues, and exercise to enhance recovery.

Longitudinal symptom network structure in first-episode psychosis: a possible marker for remission

BACKGROUND

Network approach has been applied to a wide variety of psychiatric disorders. The aim of the present study was to identify network structures of remitters and non-remitters in patients with first-episode psychosis (FEP) at baseline and the 6-month follow-up.

METHODS

Participants (n = 252) from the Korean Early Psychosis Study (KEPS) were enrolled. They were classified as remitters or non-remitters using Andreasen's criteria. We estimated network structure with 10 symptoms (three symptoms from the Positive and Negative Syndrome Scale, one depressive symptom, and six symptoms related to schema and rumination) as nodes using a Gaussian graphical model. Global and local network metrics were compared within and between the networks over time.

RESULTS

Global network metrics did not differ between the remitters and non-remitters at baseline or 6 months. However, the network structure and nodal strengths associated with positive-self and positive-others scores changed significantly in the remitters over time. Unique central symptoms for remitters and non-remitters were cognitive brooding and negative-self, respectively. The correlation stability coefficients for nodal strength were within the acceptable range.

CONCLUSION

Our findings indicate that network structure and some nodal strengths were more flexible in remitters. Negative-self could be an important target for therapeutic intervention.

The factor structure and clinical utility of clinician-rated dimensions of psychosis symptom severity in patients with recent-onset psychosis: Results of a 1-year longitudinal follow-up prospective cohort study

The classic subtype classification of schizophrenia has been removed, and DSM-5 now includes the Clinician-Rated Dimensions of Psychosis Symptom Severity (CRDPSS). In the present study, a factor analysis of the CRDPSS was performed, and we assessed whether patient classification using the derived factor structure helps predict the clinical course. The participants were 390 patients with recent-onset psychosis enrolled in the Korean Early Psychosis Cohort Study (KEPS). Two factors were identified: psychotic (including delusions, hallucinations, disorganization, and abnormal psychomotor behavior) and negative-cognitive (including negative symptoms and impaired cognition). Patients were grouped based on the factor structure and changes in clinical course were monitored over 1 year. The negative-cognitive group demonstrated longer duration of untreated psychosis, earlier onset, and a higher rate of psychiatric comorbidities. Baseline Positive and Negative Syndrome Scale (PANSS) total and Clinical Global Impression-Severity (CGI-S) scores were higher in psychotic group, but group differences were not observed after 2 months. Conversely, the PANSS negative scale score was significantly higher in negative-cognitive group throughout follow-up, and CGI-S score was reversed at 12 months. The findings indicate that the factor structure derived herein for the CRDPSS could be helpful for predicting the clinical course of recent-onset psychosis patients.

Development of the Korea-Polyenvironmental Risk Score for Psychosis

OBJECTIVE

Comprehensive understanding of polyenvironmental risk factors for the development of psychosis is important. Based on a review of related evidence, we developed the Korea Polyenvironmental Risk Score (K-PERS) for psychosis. We investigated whether the K-PERS can differentiate patients with schizophrenia spectrum disorders (SSDs) from healthy controls (HCs).

METHODS

We reviewed existing tools for measuring polyenvironmental risk factors for psychosis, including the Maudsley Environmental Risk Score (ERS), polyenviromic risk score (PERS), and Psychosis Polyrisk Score (PPS). Using odds ratios and relative risks for Western studies and the "population proportion" (PP) of risk factors for Korean data, we developed the K-PERS, and compared the scores thereon between patients with SSDs and HCs. In addition, correlation was performed between the K-PERS and Positive and Negative Syndrome Scale (PANSS).

RESULTS

We first constructed the "K-PERS-I," comprising five factors based on the PPS, and then the "K-PERS-II" comprising six factors based on the ERS. The instruments accurately predicted participants' status (case vs. control). In addition, the K-PERS-I and -II scores exhibited significant negative correlations with the negative symptom factor score of the PANSS.

CONCLUSION

The K-PERS is the first comprehensive tool developed based on PP data obtained from Korean studies that measures polyenvironmental risk factors for psychosis. Using pilot data, the K-PERS predicted patient status (SSD vs. HC). Further research is warranted to examine the relationship of K-PERS scores with clinical outcomes of psychosis and schizophrenia.

Network analysis of trauma in patients with early-stage psychosis

Childhood trauma (ChT) is a risk factor for psychosis. Negative lifestyle factors such as rumination, negative schemas, and poor diet and exercise are common in psychosis. The present study aimed to perform a network analysis of interactions between ChT and negative lifestyle in patients and controls. We used data of patients with early-stage psychosis (n = 500) and healthy controls (n = 202). Networks were constructed using 12 nodes from five scales: the Brief Core Schema Scale (BCSS), Brooding Scale (BS), Dietary Habits Questionnaire, Physical Activity Rating, and Early Trauma Inventory Self Report-Short Form (ETI). Graph metrics were calculated. The nodes with the highest predictability and expected influence in both patients and controls were cognitive and emotional components of the BS and emotional abuse of the ETI. The emotional abuse was a mediator in the shortest pathway connecting the ETI and negative lifestyle for both groups. The negative others and negative self of the BCSS mediated emotional abuse to other BCSS or BS for patients and controls, respectively. Our findings suggest that rumination and emotional abuse were central symptoms in both groups and that negative others and negative self played important mediating roles for patients and controls, respectively.

Trial Registration: ClinicalTrials.gov identifier: CUH201411002.

Mindlink: A stigma-free youth-friendly community-based early-intervention centre in Korea

AIM

In many Asian countries, youth mental health services are not well-developed and access to treatment is generally delayed. Here, we present a community-based service model based on our experience with Mindlink, the first early-intervention centre of its kind in Korea.

METHODS

We describe the history of this mental health early-intervention service and the characteristics of users, as well as its intervention programmes and research directions. We also propose ways to further develop youth mental health services.

RESULTS

A community-based early-intervention service for youth was first introduced in 2012, when a special team was formed in a community mental health centre of Korea. As the numbers of young clients increased, a youth-friendly, early-intervention centre called Mindlink was opened in 2016. Mindlink targets those aged 15-30 years with mental illness less than 5 years in duration. Its goal is to detect mental illness in young people early and provide comprehensive multidisciplinary interventions. It provides intensive case management and group programmes including cognitive-behavioural therapy, family intervention, psychoeducation, behavioural activation and physical health promotion. The Korean government has officially announced that the Mindlink model is effective and is currently in the process of scaling it up on a national level.

CONCLUSION

An accessible, youth-friendly, stigma-free, community mental health centre such as Mindlink allows early detection and appropriate management of mental illness in young patients.

The effects of patient personality traits and family cohesion on the treatment delay for patients with first-episode schizophrenia spectrum disorder

AIM

The duration of untreated psychosis (DUP) is an important prognostic indicator of schizophrenia. We explored the effects of patient personality and family relationships on delayed schizophrenia treatment.

METHODS

We prospectively included data from 169 patients diagnosed with first-episode schizophrenia. Personality traits were investigated using the Big Five Inventory (BFI-10) and family relationship was assessed employing the Family Adaptability and Cohesion Evaluation Scale-III (FACES-III). We explored patient clinical characteristics using the Positive and Negative Syndrome Scale (PANSS) and the Social and Occupational Functioning Scale (SOFAS). The DUP was defined as the time between the first appearance of psychotic symptoms and commencement of adequate antipsychotic treatment. Subjects were divided into two groups by the 3-month median DUP cutoff.

RESULTS

The average and median DUPs were 12 and 3 months, respectively. A longer DUP was associated with older age, a higher PANSS score, and a lower SOFAS score. The frequency of suicide attempts tended to be higher in the delayed treatment group (P = .055). The delayed treatment group scored significantly higher in conscientiousness factor of the BFI-10 and scored significantly lower family cohesion and adaptability factors of the FACES-III. Logistic regression showed that a longer DUP was significantly associated with higher-level conscientiousness on the BFI-10 and poorer family cohesion on the FACES-III.

CONCLUSION

Treatment delay was associated with reduced family cohesion and higher patient conscientiousness, suggesting that the family plays a crucial role in terms of patient access to mental health services when early psychotic symptoms appear.

Psychological factors intervening between childhood trauma and suicidality in first-episode psychosis

Several studies have investigated childhood trauma (ChT) and suicidality in psychosis. However, psychological factors intervening between ChT and suicidality are not well understood. The aims of this study were to explore the roles of negative schema and rumination in the relationship between ChT and suicidality in first-episode psychosis (FEP). Participants were 306 patients with FEP who were enrolled in the Korean Early Psychosis Cohort Study, a prospective naturalistic observational cohort study. ChT, suicidality, negative schema, and rumination were evaluated using the Early Trauma Inventory Self Report-Short Form, Columbia Suicide Severity Rating Scale, Brief Core Schema Scale, and Brooding Scale. In addition, psychopathology and depression were evaluated. Structural equation model and a phantom approach were employed to analyze the pathway from ChT to suicidality. We found close associations between ChT, rumination, negative schema, and suicidality. Importantly, negative schema played a direct intervening role in the relationship between ChT and suicidality in patients with FEP. Our findings suggest that targeting negative schema in individuals with FEP exposed to ChT will be an effective strategy for reducing suicidality.

Defining Treatment Response, Remission, Relapse, and Recovery in First-Episode Psychosis: A Survey among Korean Experts

OBJECTIVE

For the proper treatment of first-episode psychosis, assessment of treatment response, remission, relapse, and recovery is important. Therefore, the present study aimed to develop operational definitions of clinical outcomes in first-episode psychosis.

METHODS

A questionnaire was developed by a panel of experts and underwent three revisions. The final survey was presented to 150 psychiatrists who were members of the Korean Society for Schizophrenia Research. Respondents selected factors that they believed were important to consider while defining treatment response, remission, relapse, and recovery using a 6-point Likert scale. Selected factors that constituted each definition were statistically extracted, and operational definitions were developed.

RESULTS

A total of 91 experts responded to the survey. The extent of reduction in psychopathology, socio-occupational functioning, and duration of each state were the core factors of each definition. Outcomes obtained from discussions and consultations by experts have been summarized and proposed.

CONCLUSION

The criteria developed in this survey tended to be somewhat stricter than those used by other studies. The fundamental reason for this is that this survey focused on first-episode psychosis. A better understanding of each definition in first-episode psychosis is necessary to improve effective treatment outcomes.

Clinical and psychosocial factors associated with depression in patients with psychosis according to stage of illness

AIM

This study investigated the clinical characteristics and psychosocial factors associated with depression in patients with early psychosis according to stage of illness.

METHODS

The present study includes patients who fulfil the DSM-5 criteria for schizophrenia spectrum and other psychotic disorders. Patients were divided into two groups according to illness stage (the acute stage of first-episode psychosis and stabilization phase of recent-onset psychosis). Clinically meaningful depression was defined as moderate or severe on the depression dimension of the Clinician-Rated Dimensions of Psychosis Symptom Severity scale in the DSM-5.

RESULTS

In total, 340 (207 first-episode and 133 recent-onset) patients were recruited in this study. Patients with comorbid depression were characterized by frequent suicidal ideation, a past suicide attempt, and lower scores on the Subjective Well-being Under Neuroleptics and Brief Resilience Scale in both groups. Long duration of untreated psychosis and higher scores on the Early Trauma Inventory Self Report were associated with depression in the acute stage of first-episode psychosis. In the stabilization phase of recent-onset psychosis group, a monthly income and scores for sexual desire and on the Family Adaptability and Cohesion Evaluation Scale-III were significantly lower in patients with depression than in those without depression.

CONCLUSION

Comorbid depression was associated with high suicidality, lower quality of life and poor resilience in patients with first-episode and recent-onset psychosis. Depression was associated with factors that had been present before the initiation of treatment in patients with first-episode psychosis and with environmental factors in those in the stabilization phase.

Distinct Differences in Emotional Recognition According to Severity of Psychotic Symptoms in Early-Stage Schizophrenia

Patients with schizophrenia are characterized by deficits in their ability to identify facial expressions of emotion, which are associated with impaired social and occupational function. An understanding of the deficits of facial affect recognition (FAR) early in the course of the illness can improve early intervention efforts to ameliorate potential functional deterioration. This study aimed to investigate the characteristics and correlations between psychotic symptoms and FAR deficits in patients with early-stage schizophrenia using data from the Korean Early Psychosis Cohort Study. Patients with schizophrenia were divided into three groups: 1) severely and markedly ill (n = 112), 2) moderately ill (n = 96), and 3) mildly ill (n = 115). These groups were compared with age- and sex-matched healthy controls. The FAR test was developed using Korean emotional faces from the Korean Facial Expressions of Emotion database. Error rates, correct response times, and nonresponse rates of each subset were calculated. Several psychopathology assessments were also performed. There were significantly more deficits associated with the recognition of anger (p < 0.01), fear (p < 0.01), and contempt (p < 0.01) in the three patient groups than in the healthy control group. In the severely and markedly ill states, all emotions apart from surprise had impaired error rates (p < 0.01 for all analyses). The error rates for happiness, sadness, disgust, surprise, and neutral faces were not significantly different between mildly ill patients and healthy controls. All emotions, except for sadness, had significantly more delayed correct response times in all patient groups than in the healthy controls (p < 0.01 for all analyses). The severity of psychotic symptoms was positively correlated with the happiness and neutral error rates, and depression was positively correlated with the happiness error rates. General social function was negatively correlated with the error rates for happiness, sadness, fear, disgust, and surprise. Overall, our results show that the severity of psychosis and clinical symptoms leads to distinct differences in certain emotions of patients with early-stage schizophrenia. It is considered that these specific emotional characteristics will help deepen our understanding of schizophrenia and contribute to early intervention and recovery of social function in patients with schizophrenia.

Validation of the Korean version of the 16-Item Prodromal Questionnaire in a Non-Help-Seeking College Population

OBJECTIVE

To examine the reliability and validity of the Korean version of the 16-item Prodromal Questionnaire (KPQ-16) in non-help-seeking university students.

METHODS

Among 2,246 university students participated in the initial screening, 257 subjects with KPQ-16 scores ≥4 were interviewed. The criteria for ultra-high risk (UHR) of psychosis of the Comprehensive Assessment of At-Risk Mental States (CAARMS) were the gold standard for diagnosis. An exploratory modified version of the questionnaire (mKPQ-16), to which three items from the Eppendorf Schizophrenia Inventory were added, was also used to compensate for items on thought and cognitive problems.

RESULTS

Seventeen subjects met the CAARMS criteria for UHR of psychosis. The area under the receiver operating characteristic curve (AUROC) was highest for the mKPQ-16 total score (AUROC=0.831, p<0.001). The use of cutoff total scores of 7 for the mKPQ-16 and 6 for the KPQ-16 resulted in the best balance of sensitivity (76.5% and 64.7%, respectively) and specificity (75.4% and 71.2%, respectively).

CONCLUSION

The Korean versions of the PQ-16 are good instruments for screening for psychosis risk in university students. This validation of a questionnaire version with a small number of items may make it feasible to screen large numbers of young adults in the community.

Low dietary intake of n-3 fatty acids, niacin, folate, and vitamin C in Korean patients with schizophrenia and the development of dietary guidelines for schizophrenia

Inappropriate dietary intake and poor nutritional status are reported to be associated with metabolic syndrome and psychopathology in patients with schizophrenia. We hypothesized that inappropriate dietary habits and insufficient dietary intake of specific nutrients are associated with schizophrenia. To test the hypothesis, we assessed the dietary habits and nutritional intake of patients with schizophrenia and then developed suitable dietary guidelines. In total, 140 subjects (73 controls and 67 patients with schizophrenia from community mental health centers) were included, and dietary intakes were analyzed using a semi-quantitative food frequency questionnaire. As a result, the proportion of overweight or obese patients was significantly higher in schizophrenia subjects (64.2%) compared with control subjects (39.7%) (P=.004). The male schizophrenia patients had significantly lower dietary intakes of protein, polyunsaturated fatty acids (PUFAs), vitamin K, niacin, folate, and vitamin C than the male control subjects. In all multiple logistic regression models, subjects with the "low" dietary intake of protein, n-3 PUFAs, niacin, folate, and vitamin C had a significantly higher odds ratios for schizophrenia compared with those with the "high" dietary intake category of each nutrient. Therefore, maintenance of a healthy body weight and sufficient dietary intake of protein, PUFAs, niacin, folate, and vitamin C are recommended for Korean patients with schizophrenia.