Impact of age of onset on the course of chronic schizophrenia: factors associated with first hospitalization in a large-scale cross-sectional study.

This study aims to identify the factors influencing the age of first hospitalization in patients with chronic schizophrenia, focusing on clinical features and blood parameters. A total of 1271 patients diagnosed with chronic schizophrenia were recruited from 17 psychiatric hospitals across China. Demographic and clinical data, including age of first hospitalization, were collected. The study also included assessments of psychiatric symptoms, duration of untreated psychosis (DUP), and various blood parameters. Statistical analyses were conducted to examine the relationships between these factors and the age of first hospitalization. The average age of first hospitalization was 28.07 ± 9.993 years. Single patients and those with a family history of mental illness were hospitalized at a younger age. Patients with suicidal ideation or behavior also had an earlier hospitalization age compared to those without such history. Regression analysis revealed that marital status (single), family history of mental illness, and suicide ideation or behavior were significant risk factors for earlier hospitalization age. Conversely, DUP, total protein (TP), and low-density lipoprotein (LDL) levels were positively correlated with the age of first hospitalization, while antipsychotic medication dosage and albumin (ALB) levels were negatively correlated. The study identifies significant demographic, clinical, and biochemical factors associated with the age of first hospitalization in chronic schizophrenia patients in China. These findings underscore the importance of early intervention and targeted support for high-risk groups to improve treatment outcomes.