Comorbidities associated with COVID‑19 mortality: A retrospective study in an intermediate care facility in Cape Town, South Africa

Abstract

Background. The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic continues to place a significant burden on healthcare systems across the globe. Previous studies have shown that patients with comorbidities who contract SARS-CoV-2 develop more severe COVID‑19 disease and are at a higher risk of mortality. However, literature in the intermediate care setting is limited. Objectives. To evaluate the association between comorbidity and mortality in the intermediate care setting.Methods. A retrospective observational study was performed at Brackengate Intermediate Care Facility (BICF), a 330-bed field hospital, during the second wave of COVID‑19 in Cape Town, South Africa. Data of all adult patients admitted from 1 November 2020 to 28 February 2021 who met the inclusion criteria were analysed. Data were obtained from electronic hospital patient administration systems. Comparisons were made using χ2 or Fisher’s exact testing with a 5% level of confidence used to determine significance. Logistic regression models were used to investigate the independent association between clinical variables of interest and overall mortality.Results. A total of 2 508 patients were analysed, of whom 2 476 (98.7%) were laboratory confirmed cases of COVID‑19. The median number of admissions per day was 14. The mean age was 58 years, and 1 449 (57.8%) were female. The most prevalent comorbidities were hypertension (62.6%), diabetes (46.9%) and obesity (28.0%), while 8.0% of patients were HIV-positive. The overall mortality was 13.3% (333/2 508). Patients with at least one comorbidity were 1.4 times more likely to die (odds ratio (OR) 2.4; 95% confidence interval (CI) 1.6 - 3.5), and this risk increased significantly with cumulative comorbidities. Patients who required >40% oxygen were at 5.5 (95% CI 4.3 - 7.1) times higher mortality risk. Variables independently associated with mortality were age >60 years, FiO2>40%, previous cerebrovascular accident, concurrent tuberculosis infection and chronic kidney disease.Conclusion. Patients with comorbidities are at an increased risk of death in COVID‑19 disease, and should be monitored closely. Oxygen requirement >40% is also associated with a higher likelihood of dying. Intermediate care facilities can provide valuable relief to acute care facilities by admitting high-risk patients for closer monitoring and management.