Objective To investigate the factors influencing all-cause and specific cause deaths in community-dwelling patients with schizophrenia.

Methods The data analyzed in this study were obtained from the integrated management information platform for severe mental disorders in a region in western China. The Kaplan-Meier method and log-rank test were used to estimate and compare the cumulative incidence curves of patient deaths. Risk factors for all-cause and specific cause deaths were explored using the Cox proportional hazards regression model and Fine-Gray competing risk model, respectively.

Results A total of 207638 schizophrenia patients were included in the study, with a median follow-up period of 3.98 years and a maximum follow-up period of 12.35 years. A total of 15062 (7.3%) patients died during the follow-up period, including 8758 (4.2%) due to physical illnesses, 563 (0.3%) due to suicide, 1337 (0.6%) due to accidents, 1193 (0.6%) due to mental illness-related complications, and 3211 (1.6%) due to other causes. Multivariate Cox regression analysis revealed that age (hazard ratio HR = 3.65, 95% CI: 3.49-3.81), sex (HR = 0.78, 95% CI: 0.75-0.81), ethnicity (HR = 0.78, 95% CI: 0.61-0.99), marital status (HR = 1.24, 95% CI: 1.19-1.28), economic status (HR = 1.67, 95% CI: 1.61-1.74), educational attainment (HR = 0.69, 95% CI: 0.66-0.72), family history of psychiatric illness (HR = 0.90, 95% CI: 0.83-0.98), and the duration of illness (10-19 years HR = 0.82, 95% CI: 0.79-0.85 and 20-29 years HR = 0.79, 95% CI: 0.76-0.83) were influencing factors for all-cause deaths in patients with schizophrenia. The results of the Fine‒Gray model indicated that older age, male sex, lower educational attainment, and poverty are common risk factors for patient deaths due to physical illnesses, accidents, mental illness-related complications, and other causes. Being single, divorced, or widowed and having a shorter duration of illness are common risk factors for mortality due to physical illnesses, accidents, and other causes. Poor medication adherence was a risk factor for patient deaths due to mental illness-related complications and other causes. Additionally, for deaths due to physical illnesses, Han ethnicity and the absence of a family history of psychiatric illness were associated with a higher mortality risk. Regarding suicide deaths, higher educational attainment, poverty, shorter duration of illness, and good medication adherence were identified as risk factors.

Conclusion Targeted management and interventions should be implemented based on the different mortality risks in schizophrenia patients to improve their survival rates.