COVID-19(20) Patient(11) patients with COVID-19(10) coronavirus disease(10) in-hospital mortality(8) Analysis(8) patients(8) Coronavirus disease 2019(7) disease(7) with COVID-19(7) Japan(7) Mortality(7) enrolled(7) 95% confidence interval(6) COVID-19 infection(6) Hospitalization(6) retrospective(6) association(5) Treatment(5) increased risk(5) Prognosis(5) cardiovascular disease(5) syndrome(5) severe COVID-19(4) male(4) reported(4) Diabetes Mellitus(4) Primary outcome(4) Factor(4) Admission(4)