Viral sepsis-induced mortality of older patients infected by the Omicron subvariant BA.5 of SARS-CoV-2: a retrospective study.

backgroundThe infection by the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among the older population induced viral sepsis and put them at high risk of severity and mortality.

methodsWe retrospectively investigated 268 patients infected with the Omicron variant of SARS-CoV-2 and hospitalized in two tertiary medical centers in Jiangsu Province, China, from December 2022 to January 2023, who met the Sepsis- 3 criteria. Patients were divided into the survivor (n = 111) and non-survivor (n = 157) groups, and their baseline clinical characteristics, including their demographic information, medical history, clinical manifestation, laboratory test results, arterial blood gas profiles and computed tomography (CT) patterns, were compared between the two groups to evaluate the risk factors for in-hospital death caused by viral sepsis.

resultsThe median age of the patients hospitalized was 78.5 (IQR: 71.3-84.8), and 69.0% of them were male. 45.9% of the patients were aged ≥ 80 years. From illness onset to hospitalization the median length of time was 7 days, while the duration of hospitalization was 10.0 days (IQR: 6.0-20.8) and the stay in the intensive care unit (ICU) was 7.0 days (IQR: 4.0-14.0). The median cycle threshold (Ct) values for ORF1ab and N gene amplification were 30.3 and 29.2, respectively. Hypertension, diabetes, and cardiovascular diseases prevailed in the patients' comorbidity list. After laboratory parameters, arterial blood gas exchange profiles, and radiological patterns were examined, a substantial impact of multiple organ dysfunctions induced by Omicron subvariant BA.5 infection was observed in both groups. As a result, the Sequential Organ Failure Assessment (SOFA) score was significantly factorial in the in-hospital mortality of older patients with COVID-19 (a fatality rate of 58.6%), consistent with determinants in death from non-viral sepsis.

conclusionWith the Omicron subvariants having lower pathogenicity but higher transmissibility compared to pre-Omicron variant of concern (VOC), the older population remains the most vulnerable to COVID-19 infection, which could lead to sepsis and septic shock, highlighting the importance of timely booster vaccinations.