Age-matched versus non-age-matched comparison of clinical and functional differences between delusional disorder and schizophrenia: a systematic review.

Background: It has been widely suggested that delusional disorder (DD) differs from schizophrenia (SZ). However, whether the two disorders are truly distinct from each other is inconclusive as an older age of onset is closely linked to a better prognosis in psychotic disorders. In order to delineate the potential influence of age on outcomes, we undertook a systematic review on the clinical and functional differences between DD and SZ in age-matched and non-age-matched cohorts. Methods: Electronic databases were retrieved up to May 2022. Included studies were analyzed with reference to statements about clinical, cognitive and functional differences between DD and SZ. Results: Data synthesized from 8 studies showed (1) extensive effects of age on positive, general psychopathological symptoms and functioning, but (2) consistent differences between the two disorders in terms of negative symptoms and hospitalizations regardless of age matching. Conclusion: There is currently insufficient evidence to conclude whether DD is completely distinct from SZ, but our review showed support for the confounding effect of age in comparisons of psychotic disorders with different ages of onset. Future studies shall take note of other possible confounding variables, methods of age-matching and the importance of longitudinal information in deducing whether the two disorders differ from each other in course and outcome.

Functional and clinical outcomes of delusional disorder and schizophrenia patients after first episode psychosis: a 4-year follow-up study.

BACKGROUND: Literature has typically associated delusional disorder with a poorer prognosis relative to schizophrenia, without considering the confounding effect of age despite the differential age of onset. This study therefore aims to investigate the diagnostic stability, clinical, functional, and neurocognitive differences of Chinese first-episode psychosis age-matched patients with delusional disorder and schizophrenia at four years. METHODS: 71 delusional disorder and 71 age-matched schizophrenia patients were followed up for four years after their initial episode. Their symptoms, insight in psychosis, side effects of medication, medication compliance, functioning, and neurocognitive performance were assessed at four years. RESULTS: At four years, 65% of DD patients maintained the same diagnosis, while the rest shifted to SZ. Only those without a diagnostic shift were included in the analysis. Delusional disorder patients (n = 46) experienced greater general psychopathology and poorer insight, but better attitude towards medication than schizophrenia patients (n = 71). Social and occupational functioning, quality of life, and cognitive functioning, however, were similar in delusional disorder and schizophrenia patients. CONCLUSIONS: Results indicate that delusional disorder is less diagnostically stable than schizophrenia. Their outcomes in a Chinese population were largely similar at four years after removing the confounding age factor, implying that delusional disorder and schizophrenia may not be as distinct as previously thought.

Effectiveness and optimal duration of early intervention treatment in adult-onset psychosis: a randomized clinical trial.

BACKGROUND: Contrasting the well-described effects of early intervention (EI) services for youth-onset psychosis, the potential benefits of the intervention for adult-onset psychosis are uncertain. This paper aims to examine the effectiveness of EI on functioning and symptomatic improvement in adult-onset psychosis, and the optimal duration of the intervention. METHODS: 360 psychosis patients aged 26-55 years were randomized to receive either standard care (SC, n = 120), or case management for two (2-year EI, n = 120) or 4 years (4-year EI, n = 120) in a 4-year rater-masked, parallel-group, superiority, randomized controlled trial of treatment effectiveness (Clinicaltrials.gov: NCT00919620). Primary (i.e. social and occupational functioning) and secondary outcomes (i.e. positive and negative symptoms, and quality of life) were assessed at baseline, 6-month, and yearly for 4 years. RESULTS: Compared with SC, patients with 4-year EI had better Role Functioning Scale (RFS) immediate [interaction estimate = 0.008, 95% confidence interval (CI) = 0.001-0.014, p = 0.02] and extended social network (interaction estimate = 0.011, 95% CI = 0.004-0.018, p = 0.003) scores. Specifically, these improvements were observed in the first 2 years. Compared with the 2-year EI group, the 4-year EI group had better RFS total (p = 0.01), immediate (p = 0.01), and extended social network (p = 0.05) scores at the fourth year. Meanwhile, the 4-year (p = 0.02) and 2-year EI (p = 0.004) group had less severe symptoms than the SC group at the first year. CONCLUSIONS: Specialized EI treatment for psychosis patients aged 26-55 should be provided for at least the initial 2 years of illness. Further treatment up to 4 years confers little benefits in this age range over the course of the study.

Working memory deterioration as an early warning sign for relapse in remitted psychosis: A one-year naturalistic follow-up study.

BACKGROUND: Relapse prevention is an important goal in the clinical management of psychosis. Cognitive deficits/deterioration can provide useful insights for monitoring relapse in psychosis patients. METHODS: This was a prospective, naturalistic 1-year follow-up study involving 110 psychosis patients with full clinical remission. Relapse, defined as the recurrence of psychotic symptoms, was monitored monthly along with digital tracking of verbal and visual working memory using a mobile app developed for this study. Cognitive deterioration was defined as worsening performance over 2 months prior to relapse or study termination, whichever was earlier. Other clinical, cognitive, functioning, and psychosocial variables were also collected. RESULTS: At 1 year, 18 (16.36%) patients relapsed, of which 6 (33.33%) required hospitalization. Relapse was predicted by verbal working memory deterioration 2 months prior to relapse (p = 0.029), worse medication adherence (p = 0.018), and less resilience (p = 0.014). CONCLUSIONS: Verbal working memory deterioration is a novel early sign of relapse. It is a clearly defined, objectively measurable, and reproducible marker that can help clinicians and healthcare workers identify patients at risk of relapse and make decisions about maintenance therapy. Moreover, digital monitoring is a viable tool in the management of relapse.

Correlates and predictors of perceived stigma and self-stigma in Chinese patients with psychosis.

AIMS: In patients with psychosis, perceived stigma (i.e., beliefs about discriminative viewpoints held by the public) and self-stigma (i.e., internalization of such perceived stereotypes) could have devastating consequences. Knowledge about their correlates bears importance for understanding individual differences in stigma experiences, and further, given the social nature of stigma, Asians may show more distinctive features than Westerners. METHODS: A total of 142 Chinese patients who originally enrolled into a randomized controlled trial during their first-episode psychosis were followed up at 10 years. We explored potential demographics, clinical and psychosocial correlates of perceived stigma and self-stigma. RESULTS: Stepwise multiple regression analyses indicated that both perceived- and self-stigma were predicted by a more negative attitude to treatment, whereas differential factors including perceived recovery predicted perceived stigma, and quality of life and attention predicted self-stigma. CONCLUSIONS: These results can help identify individuals susceptible to experiencing perceived- or self-stigma, highlighting the need to consider factors such as attitude towards treatment when designing anti-stigma strategies.

Mindfulness meditation for Chinese patients with psychosis: A systematic review and meta-analysis.

Mindfulness meditation (MM) and its alignment with the mind-body perspective of health in Chinese cultures indicate its potential to benefit Chinese patients with psychosis. This is the first systematic review and meta-analysis to address the following questions: (1) Does MM improve clinical, well-being, and third-wave outcomes (i.e., mindfulness, acceptance, and compassion levels) among Chinese patients with psychosis? (2) What are the patient- and/or intervention-specific factors that moderate the efficacy of MM? (3) Are improvements on third-wave outcomes associated with improvements on clinical and well-being outcomes? (4) What are the mechanisms underlying the effects of MM? Evidence synthesized from 23 relevant articles (20 studies) involving 1749 patients showed that (1) MM improved a wide range of patients' outcomes, most consistently and sustainably for insight, rehospitalization duration, recovery rate, and social functioning; (2) age and duration of illness, but not the cumulated intervention hours, moderated the overall efficacy of MM; (3) post-MM improvements on mindfulness and on clinical and well-being outcomes were related, and (4) the effects of MM on patients' outcomes may be driven by its ability to promote positive changes in personal growth and enhance one's coping with the illness and its symptoms. Our data showed preliminary support for the benefits of MM in Chinese patients with psychosis. However, results should be considered in light of the varying quality of included studies and their heterogeneity in multiple aspects. Further research is needed to deduce the sustainability of MM's effects, its active ingredients, underlying mechanisms, and additional moderators of its efficacy.