Construction Of Warning Model For Mortality Of COVID-19 And A Prospective Cohort Study On The Prognosis Of Older COVID-19 Patients

Objective:Extensive screening of risk factors related to disease progression and prognosis from epidemiological characteristics,serological indicators,clinical symptoms and comorbidity,the risk factors related to in-hospital death of patients with novel coronavirus pneumonia（COVID-19）were extensively screened and an early warning model was constructed.And then,systematically evaluate the prognosis of older COVID-19 recoverers one year after hospital discharge and their potential prognostic risk factors.It is used to assist clinicians in judging the condition and evaluating the prognosis of patients.Methods:This study consists of two parts.In the first part,4,086 COVID-19 patients were recruited from Wuhan Huoshenshan Hospital and Wuhan Taikang Tongji Hospital from February 12^th,2020 to April 10^th,2020.The first part is to establish and validate a warning model for in-hospital deaths of COVID-19 patients:a total of 3,022 COVID-19 cases in Wuhan Huoshenshan Hospital were chronologically divided into two groups,one（1,780,including 47deaths）for nomogram modeling,and the other（1,242,including 22 deaths）for internal validation.We then recruited 1,064 COVID-19 cases（29 deaths）in Wuhan Taikang-Tongji Hospital for external validation.The second part is to evaluate the prognosis of older people who have recovered from COVID-19:1,233 elderly patients with novel coronavirus pneumonia were followed up from March 1^st,2021 to March 20^th,2021,and the CAT score was used to measure the symptom burden of COVID-19 patients.Results:（1）8 independent factors included age（HR:1.05 with increasing years）,severity at admission（HR:2.91 with increasing levels）,dyspnea（HR:2.18）,cardiovascular disease（HR:3.25）,and lactate depletion.Hydrogenase level（HR:4.53）,total bilirubin（HR:2.56）,blood glucose（HR:2.56）,urea（HR:2.14）were finally selected for constructing the nomogram.（2）Internal resampling（0.97,95%CI:0.95-0.98）,internal validation（0.96,95%CI:0.94-0.98）and external validation（0.92,95%CI:0.86-0.98）for the constructed predictive model)of the C-index showed better discriminative ability.Calibration plots show the best agreement between nomogram predictions and actual observations.（3）Among 1233 eligible older COVID-19 recoverers,630（51.1%）patients reported at least one sequelae at one-year follow-up after discharge.The top six sequelae included fatigue（32.4%）,sweating（20.0%）,chest tightness（15.8%）,anxiety（11.4%）,myalgia（9.0%）and cough（5.8%）.Severe patients had significantly higher proportions of fatigue,sweating,chest tightness,myalgia and cough compared with non-severe patients（P<0.05）,while anxiety was common in all older recoverers.Sweating,anxiety,palpitations,lower extremity edema,hyposmia,and altered taste are new symptoms.（4）Disease severity during hospitalization（OR:1.46,95%CI:1.15-1.84,P=0.002）and follow-up time（OR:0.71,95%CI:0.50-0.99,P=0.043）were associated with the occurrence of sequelae Risk was independently associated,while disease severity during hospitalization was significantly associated with an increased risk of developing sequelae（OR:1.33,95%CI:1.03-1.71,P=0.029）.（5）The median CAT score of all patients was 2（0-5）,and a total of 120 patients（9.7%）had a CAT score of≥10.Disease severity during hospitalization（OR:1.81,95%CI:1.23-2.67,P=0.003）and age（OR:1.07,95%CI:1.04-1.09,P<0.001）were significantly associated with an increased risk of a CAT score≥10.related.Conclusion:（1）A novel prognostic nomogram was established and validated to predict in-hospital mortality in patients with COVID-19.（2）In follow-up of older COVID-19 reciverers one year after discharge from hospital,fatigue was the most common sequelae,followed by sweating.（3）Disease severity,age,and follow-up time during hospitalization can affect the prognosis and CAT score of older COVID-19 recoverers one year after discharge.