Risk factors for poor COVID-19 outcomes in patients with psychiatric disorders

•Cause of higher risk for COVID-19 poor outcome in psychiatric patients is unclear.•A shorter duration to in-hospital mortality was observed in psychiatric patients.•Psychiatric patients had higher vaccination rates and lower inflammatory markers.•Antipsychotic use was associated with in-hospital mortality.•Monitor patients and use psychotropics cautiously first few days after infection. Coronavirus disease 2019 (COVID-19) has been found to have a greater impact on individuals with pre-existing psychiatric disorders. However, the underlying reasons for this increased risk have yet to be determined. This study aims to investigate the potential factors contributing poor outcomes among COVID-19 patients with psychiatric disorders, including delayed diagnosis of infection, vaccination rates, immune response, and the use of psychotropic medications. This retrospective cohort study analyzed medical records of 15,783 adult patients who were diagnosed with COVID-19 infection by positive PCR tests between January and September 2022 at a single medical center. We identified psychiatric diagnoses using ICD-9 diagnostic codes from the preceding 3 years before COVID infection. Primary outcome was in-hospital mortality and secondary outcomes were severe illness requiring intensive care or mechanical ventilation, and hospitalization within 45 days after a positive COVID-19 test. We compared the rates of outcomes, viral load, vaccination status at the time of positive test, psychotropic medications prescription within 90 days prior, antiviral medication use, and blood inflammation markers between patients with and without psychiatric disorders. The Cox proportional hazard model was used to examine the association of psychiatric diagnoses, vaccination status, and psychotropic medication prescription with poor outcomes. Patients with psychiatric disorders demonstrated higher rates of severe illness (10.4% v.s. 7.1%) and hospitalization (16.4% vs. 11.3%), as well as a shorter duration to in-hospital mortality (6 vs. 12.5 days) compared to non-psychiatric patients. Psychiatric patients had higher vaccination rates and lower levels of inflammatory markers than non-psychiatric patients. Antipsychotic medication use was associated with in-hospital mortality (hazard ratio [HR] = 4.79, 95% confidence interval [CI] = 1.23–18.7), while being unvaccinated was associated with hospitalization (HR = 1.81, 95% CI = 1.29 to 2.54) and severe illness (HR = 3.23, 95% CI = 1.95 to 5.34) among