Objective: To investigate the cumulative effect of antipsychotics at different dosages on mortality in patients with schizophrenia. Methods: We analyzed data from the Korean National Health Insurance System−National Sample Cohort covering the 2002−2013 period. We used Cox regression analysis to calculate hazard ratios for mortality risks according to cumulative antipsychotic exposure levels (low, moderate, and high). Results: Our analyses revealed no significant association between antipsychotic exposure and mortality (either all-cause or cause-specific) in patients with schizophrenia. Conclusion: Our results imply that the excess mortality of patients with schizophrenia is attributable to factors other than antipsychotic usage.

Background The objective of this study was to investigate the trend of self-injurious behavior (SIB) among persons who were directly impacted by coronavirus disease 2019 (COVID-19), especially those with pre-existing mental disorders. Methods Using the National Health Insurance Service-COVID-19 database cohort, the monthly SIB rate was calculated by COVID-19 subgroups (i.e., positive for COVID-19 test, negative for COVID-19 test, and non-COVID-19 test [control]). In addition, moderated regression analysis was utilized to examine the statistical difference of SIB (suicide attempt and non-suicidal self-injury using ICD-10 code) trend between COVID-19 subgroups and with and without pre-existing mental disorder. Results A total of 328,373 persons were included in the cohort study. Of these, 212,678 had been tested for COVID-19, and 7,713 of them were confirmed positive. During the pandemic peak, the “negative for COVID-19” group showed a large increase ( P = 0.003) in SIB rates compared to the control group, the “positive for COVID-19” group showed a decreasing trend, but not significant ( P = 0.314). Among those who were tested for COVID-19, those with pre-existing mental disorders showed an increasing trend of SIB compared to those without pre-existing mental disorders, however statistically insignificant ( P = 0.137). Conclusion Our results suggest that people who are tested for COVID-19 are at a high risk of SIB during the peak COVID-19 pandemic. Therefore, screening for suicide risk and psychological interventions is needed for these high-risk groups.