Diagnostic stability and long-term outcomes of acute and transient psychotic disorders: a systematic review and meta-analysis
Background To examine the diagnostic stability and long-term outcomes of acute and transient psychotic disorders (ATPD), with particular attention to subsequent diagnostic transitions and relapse over time. Methods A systematic search of PubMed, Embase, Web of Science, the Cochrane Library, as well as Chinese databases including CNKI, Wan fang, and VIP, was conducted from database inception to March 1, 2026. Observational studies reporting follow-up outcomes in patients initially diagnosed with ATPD were eligible. Data extraction and quality assessment were performed independently by two reviewers. Pooled proportions were estimated using random-effects models, and statistical analyses were conducted using R software (version 4.5.1). Results A total of 14 studies involving 12,920 participants were included. The pooled proportion of diagnostic stability was 0.41 (95% CI: 0.34–0.51), while 0.50 (95% CI: 0.36–0.63) of patients experienced any diagnostic change. Transition to schizophrenia spectrum disorders occurred in 0.39 (95% CI: 0.29–0.50) of cases, whereas transition to mood disorders was less frequent (0.19, 95% CI: 0.12–0.30). The pooled relapse rate was 0.43 (95% CI: 0.29–0.58). Conclusions ATPD appears to show limited diagnostic stability, with a considerable proportion of patients experiencing diagnostic change over time. Transitions to schizophrenia spectrum disorders are relatively common, whereas affective outcomes are less frequent. However, substantial heterogeneity across studies limits the certainty of these estimates. These findings underscore the need for cautious interpretation of early diagnoses and highlight the importance of longitudinal follow-up. Further prospective studies with standardized methodologies are warranted. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420261347946, identifier CRD420261347946.