Finding risk factors for dementia in patients with schizophrenia: a population-based case-control study

Individuals with schizophrenia are at increased risk of dementia. However, the contributions of comorbidities and antipsychotic use remain unclear. Therefore, this study aimed to construct a clinical pathway network to clarify the relationship between schizophrenia-associated comorbidities, antipsychotic exposure, and dementia risk. This was a nationwide case-control study using Taiwan’s National Health Insurance Research Database, including 147 patients with schizophrenia who developed dementia and 882 matched controls. Comorbidities and medications were assessed before and after the schizophrenia diagnosis. Conditional logistic regression with false discovery rate correction and path analysis was performed. A total of 16 dementia-associated factors were identified across the two periods. Path analysis revealed complex temporal interrelationships, whereas associations with antipsychotic use did not persist after multivariate adjustment. Dementia risk in schizophrenia is primarily driven by comorbidities and their temporal interactions rather than by antipsychotic use. Therefore, early identification and management of comorbidities are crucial.