Clinical factors for all-cause mortality in people with schizophrenia: A retrospective cohort study between 2013 and 2021.

Background: Schizophrenia is a severe mental illness associated with significantly elevated mortality rates. However, factors related to the mortality risk among people with schizophrenia in low and middle-income countries remain to be examined. This study aims to explore the clinical factors for all-cause mortality in people with schizophrenia.

Methods: We conducted a 9-year retrospective cohort study on people with schizophrenia in Guangzhou, China. Cox proportional hazards regression analysis and competing risk analysis was used to identify clinical factors associated with all-cause mortality and specific-cause mortality. A propensity score matching method was performed to minimize the impact of confounding factors.

Results: The overall age-standardized mortality rate in people with schizophrenia between 2013 and 2021 was 1606.04 per 100,000 person-years. We found that medical expenses not covered by medical insurance (adjusted hazard ratio [aHR]: 2.49 [95 % CI: 2.21-2.82]), relatively-stable (aHR: 1.18 [95 % CI: 1.01-1.38]) and unstable illness (aHR: 2.65 [95 % CI: 1.90-3.68]), history of non-continuous treatment (aHR: 1.35 [95 % CI: 1.25-1.46]), and no treatment history (aHR: 1.41 [95 % CI: 1.29-1.55]) were associated with a higher risk of all-cause mortality. Frequent hospital stays (once: aHR: 0.46 [95 % CI: 0.42-0.50], more than once: aHR: 0.23 [95 % CI: 0.21-0.26]) and a family history of mental disorders (aHR: 0.50 [95 % CI: 0.40-0.64]) were associated with a lower risk of mortality.

Conclusion: We identified clinical factors associated with all-cause mortality. Targeted interventions should be developed to reduce the mortality risk in people with schizophrenia.