Abstract Objective This study aims to provide an academic summary of the clinical characteristics, outcomes and risk factors associated with prolonged hospital stays among the patients with varying renal function statuses during the Omicron pandemic in Shanghai. Methods Clinical data was collected from COVID-19 patients admitted to Shanghai Jiaotong University School of Medicine Ruijin Hospital Northern District. Based on their baseline eGFR, the patients were divided into three groups: Group A (eGFR > = 90ml/min/1.73m2, n = 384), Group B (15ml/min/1.73m2