WHODAS 2.0: Associations of functional disability with sex, age, and length of care in outpatients with schizophrenia-spectrum disorders

Sex differences in schizophrenia spectrum disorders: insights from the DiAPAson study using a data-driven approach

PURPOSE

Schizophrenia Spectrum Disorders (SSD) display notable sex differences: males have an earlier onset and more severe negative symptoms, while females exhibit affective symptoms, better verbal abilities, and a more favourable prognosis. Despite extensive research, areas such as time perception and positivity remain underexplored, and machine learning has not yet been adequately utilised. This study aims to address these gaps by examining sex differences in a sample of Italian patients with SSD using a data-driven approach.

METHODS

As part of the DiAPAson project, 619 Italian patients with SSD (198 females; 421 males) were assessed using standardised clinical tools. Data on socio-demographics, clinical characteristics, symptom severity, functioning, positivity, quality of life (QoL), and time perspective were collected. Descriptive and regression analyses were conducted. Principal Component Analysis (PCA) and the Gaussian Mixture Model (GMM) was used to define data-driven clusters. A leave-one-group-out validation was performed.

RESULTS

Males were more likely to be single (p < 0.001) and less educated (p = 0.006), while females smoked more tobacco (p = 0.011). Males were more frequently prescribed antipsychotics (p = 0.022) and exhibited more severe psychiatric (p = 0.004) and negative symptoms (p = 0.013). They also had a less negative perception of past events (p = 0.047) and a better view of their psychological condition (p = 0.004). Females showed better interpersonal functioning (p = 0.008). PCA and GMM revealed two main clusters with significant sex differences (p = 0.027).

CONCLUSION

This study identifies sex differences in SSD, suggesting tailored treatments such as enhancing interpersonal skills for females and maintaining positive self-assessment for males. Using machine learning, we highlight distinct SSD phenotypes, emphasising the need for sex-specific interventions to improve outcomes and QoL. Our findings stress the importance of a multifaceted, interdisciplinary approach to address sex-based disparities in SSD.

TRIAL REGISTRATION

ISRCTN registry ID ISRCTN21141466.

Assessing functional disability in schizophrenia patients receiving the Management and Treatment Services for Psychosis in China: Implications for community mental health services

BACKGROUND

The Management and Treatment Services for Psychosis (MTSP), as a core of China's community mental health services, has served over 4 million long-term schizophrenia patients. However, the functioning and disability status of these patients is underreported. This study aims to assess their functional disability and investigate the daily influencing factors, to better inform future service planning and provision.

METHODS

This cross-sectional survey was conducted at the MTSP Service Points in 12 communities in Changsha, Hunan Province. The World Health Organization Disability Assessment Schedule II (WHODAS 2.0) was used to measure functional disability in 457 patients with schizophrenia. The mean disability summary score was compared to population norms and published outpatient samples, and domain-specific scores were compared pairwise. Between-group comparisons and multivariate linear regression were conducted to investigate the influence of socio-demographic, clinical, and service utilization factors on patients' functional disability.

RESULTS

Participants had a mean disability summary score of 29.1, exceeding the 94th percentile of the population distribution and higher than outpatient counterparts. Self-care was the least impaired domain, while social participation was the most impaired. Service non-utilization, including delay of first treatment (B = 2.684, P = 0.048) and last-year treatment non-adherence (B = 7.515, P < 0.001), was significantly associated with functional impairment. However, multivariate linear regression also revealed a positive relationship between the duration of receiving the MTSP (B = 0.868, P = 0.003) and disability.

CONCLUSIONS

Despite receiving the MTSP, community patients with schizophrenia exhibited severe functional impairment. To facilitate functional recovery, the MTSP should enhance its quality and diversify service scope, including more social functioning training, service utilization assistance, accessing social resources, and fostering an inclusive community environment.

Psychosis superspectrum II: neurobiology, treatment, and implications

Alternatives to traditional categorical diagnoses have been proposed to improve the validity and utility of psychiatric nosology. This paper continues the companion review of an alternative model, the psychosis superspectrum of the Hierarchical Taxonomy of Psychopathology (HiTOP). The superspectrum model aims to describe psychosis-related psychopathology according to data on distributions and associations among signs and symptoms. The superspectrum includes psychoticism and detachment spectra as well as narrow subdimensions within them. Auxiliary domains of cognitive deficit and functional impairment complete the psychopathology profile. The current paper reviews evidence on this model from neurobiology, treatment response, clinical utility, and measure development. Neurobiology research suggests that psychopathology included in the superspectrum shows similar patterns of neural alterations. Treatment response often mirrors the hierarchy of the superspectrum with some treatments being efficacious for psychoticism, others for detachment, and others for a specific subdimension. Compared to traditional diagnostic systems, the quantitative nosology shows an approximately 2-fold increase in reliability, explanatory power, and prognostic accuracy. Clinicians consistently report that the quantitative nosology has more utility than traditional diagnoses, but studies of patients with frank psychosis are currently lacking. Validated measures are available to implement the superspectrum model in practice. The dimensional conceptualization of psychosis-related psychopathology has implications for research, clinical practice, and public health programs. For example, it encourages use of the cohort study design (rather than case-control), transdiagnostic treatment strategies, and selective prevention based on subclinical symptoms. These approaches are already used in the field, and the superspectrum provides further impetus and guidance for their implementation. Existing knowledge on this model is substantial, but significant gaps remain. We identify outstanding questions and propose testable hypotheses to guide further research. Overall, we predict that the more informative, reliable, and valid characterization of psychopathology offered by the superspectrum model will facilitate progress in research and clinical care.