Evaluating the Mode of Presentation to Hospital and Time to Death/Discharge in Patients with COVID-19 in Southwest Iran: A Joint Modelling Approach

Background and Objective: Recently, coronavirus has become a major cause of death and hospital admission worldwide. This study was aimed to assess the factors associated with the presentation via ambulance and time to in-hospital death or discharge from the hospital using a multilevel joint modeling approach. Materials and Methods: In this historical cohort study, hospitalized patients with COVID-19 were included from 34 medical centers in Khuzestan province, Iran, from February 18th, 2020, to January 5th, 2021. Joint model analysis was used to assess the impact of demographic and clinical characteristics on the mode of hospital presentation and time to death/discharge from hospitals in Khuzestan province, Iran. Results: Among 22,356 patients, 14.2% presented to the hospital via ambulance, and 11.2% died in the hospital. The odds of ambulance use was higher in patients with older age, male sex, comorbidities including respiratory disease, diabetes, cancer, and drug abuse, and symptoms such as respiratory distress and loss of consciousness. Older age, male sex, a higher burden of comorbidities, symptoms of chest pain, respiratory distress, and loss of consciousness, and admission to intensive care unit were predictors of in-hospital mortality. The median survival time was longer for patients with COVID-19 who self-presented to the hospital compared to those who presented with ambulance (31 vs 20 days; log-rank P<0.001). Conclusion: Several demographic and clinical factors were found to predict the EMS utilization and in-hospital mortality in patients hospitalized with COVID-19 and can be used for risk-stratification. Controlling for the predictors of ambulance use in COVID-19 infection may help improve patient outcomes.