Non-cognitive symptoms as early indicators of Dementia: A retrospective study from a Psychiatric outpatient clinic

Introduction : Neuropsychiatric symptoms (NPS) may signal dementia risk or early pathology, yet clinical evidence linking pre-diagnostic NPS to outcomes remains limited. This study explored NPS features and their associations with dementia progression. Methods : Retrospective analysis of 201 dementia patients from Shanghai Mental Health Center (ICD-10 diagnosed). NPS history was extracted from medical records. Statistical analyses included chi-square tests (demographics/subtypes), ANOVA (preclinical intervals), and logistic regression (AD vs. non-AD predictors). Results : 69.2% of patients had pre-dementia NPS, accelerating progression to dementia (23.4 vs. 42.2 months, p < 0.001) and increasing non-AD dementia risk. Psychiatric disorders (74.1%) were the most prevalent NPS domain, followed by sleep disturbances (46.8%) and affective dysregulation (39.8%), with psychiatric symptoms showing the shortest dementia transition (34.3 ± 37.8 months). Females exhibited higher hallucination/delusion rates than males (30.2% vs. 15.4%; 26.2% vs. 9.6%). AD predominated (68.7%), followed by DLB (12.4%) and others. Psychiatric-to-dementia intervals differed significantly between AD (52.3 ± 47.6months) and DLB (26.5 ± 19.9months). Female sex, hallucinations, and behavioral dysregulation independently predicted AD (p < 0.05). Conclusion : Pre-dementia NPS, particularly psychiatric manifestations, may hasten dementia onset and influence subtype trajectories. Clinicians should consider prodromal dementia in older adults with new-onset psychiatric symptoms to enable early intervention.