Retrospective study of comparison of clinical severity and outcome of hospitalised COVID-19 patients during the first and second waves of the pandemic in India

ObjectivesTo compare the clinical severity and outcome of hospitalised patients during the two waves of the COVID-19 pandemic in India.SettingA tertiary care referral hospital in South India.ParticipantsSymptomatic SARS CoV-2 reverse transcriptase PCR positive patients presenting to the emergency department during the two waves were recruited. The first wave spanned between April and December 2020 and the second wave between April and May 2021.Primary and secondary outcome measuresThe primary outcome of interest was mortality. Secondary outcomes included illness severity at presentation, need for oxygen therapy, non-invasive ventilation (NIV) and hospital or intensive care unit admission.ResultsThe mean (SD) age of the 4971 hospitalised patients in the first wave was similar to the 2293 patients in the second wave (52.5±15.4 vs 52.1±15.1 years, p=0.37). When compared with the first wave, during the second wave, a higher proportion of patients presented with critical illness (11% vs 1.1%, p