Jeong Yeon Seon

Purpose: The first coronavirus disease (COVID-19) spike and subsequent pandemic in South Korea were rapid and disruptive. Government response measures for disadvantaged groups against infectious disease should be prioritized based on evidence and affordability. We investigated whether COVID-19 infection, intensive care unit (ICU) care, and mortality from COVID-19 are related to social and medical vulnerability, including tuberculosis (TB). Patients and Methods: Using the National Health Insurance Service COVID-19 database in South Korea, we analyzed 129,128 patients, including controls, from 1 January to 30 May 2020, during the early stage of the COVID-19 epidemic. The relationship between health insurance premiums (representing socioeconomic status), the Charlson comorbidity index (CCI) score for the severity of the underlying disease, and additional TB diagnosis was analyzed using the chi-square test and logistic regression. Results: For the demographics, 3244 out of 51,783 men (6.3%) and 4836 out of 77,345 women (6.3%) were infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). COVID-19 infection, ICU care, and mortality were related to older age (p < 0.001) and lower health insurance premium levels (p < 0.05). Regarding the CCI score, the CCI score, COVID-19 infection, and mortality increased (p < 0.0001). In terms of premium level, the highest group showed a lower risk of infection (OR 0.52, 0.48-0.57, p = 0.004), ICU care (OR 0.59, 0.46-0.75, p < 0.001), and mortality (OR 0.51, 0.32-0.78, p = 0.016) than the medical aid group. TB was related to ICU care for COVID-19 (OR 4.27, 1.27-14.38, p = 0.018). Conclusion: In the early epidemic, SARS-CoV-2 infection, ICU admission, and mortality from COVID-19 increased in socioeconomically and physically vulnerable groups. However, the relationship between tuberculosis, COVID-19 and mortality was not definite because of the possible under-reporting of TB cases and the relatively small number of TB patients.

In South Korea, 4.5% patients of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were readmitted to hospitals after discharge. However, there is insufficient research on risk factors for readmission and management of patients after discharge is poor. In this study, 7590 confirmed coronavirus disease (COVID-19) patients were defined as a target for analysis using nationwide medical claims data. The demographic characteristics, underlying diseases, and the use of medical resources were used to examine the association with readmission through the chi-square test and then logistic regression analysis was performed to analyze factors affecting readmission. Of the 7590 subjects analyzed, 328 patients were readmitted. The readmission rates of men, older age and patients with medical benefits showed a high risk of readmission. The Charlson Comorbidity Index score was also related to COVID-19 readmission. Concerning requiring medical attention, there was a higher risk of readmission for the patients with chest radiographs, computed tomography scans taken and lopinavir/ritonavir at the time of their first admission. Considering the risk factors presented in this study, classifying patients with a high risk of readmission and managing patients before and after discharge based on priority can make patient management and medical resource utilization more efficient. This study also indicates the importance of lifestyle management after discharge.