Predictors of mortality in acute hospitalised COVID-19 pneumonia patients: A retrospective cohort study at two tertiary-level hospitals in Zambia

Abstract

Background. The global COVID-19 pandemic has resulted in increased acute hospitalisations, a high demand for intensive care and high in-hospital mortality, placing a huge burden on healthcare systems. Objectives. To assess in-hospital mortality outcomes and associated factors in acute hospitalised COVID-19 pneumonia patients in Zambia. Methods. We performed a retrospective cohort review of patients admitted to two tertiary-level hospitals in Zambia from 1 March 2020 to 28 February 2021. We examined the factors (demographic, clinical and laboratory) that were associated with in-hospital mortality using multivariate logistic analysis. Adjusted odds ratios with their 95% confidence intervals (CIs) are reported. Results. Of 350 patients, 59.4% were aged ≥55 years and 52.6% were male. The commonest comorbidities were hypertension, diabetes mellitus (DM), HIV/AIDS and chronic kidney disease (49.6%, 28.5%, 22.0% and 8.1%, respectively). The overall in-hospital mortality rate was 42.6%, and mortality was significantly increased in patients aged ≥55 years (52.0% v. 48.0%) and in those with DM (52.1% v. 47.9%), cardiac disease (68.0% v. 32.0%), a Quick Sequential (Sepsis-Related) Organ Failure Assessment (q-SOFA) score ≥2 (75.4% v. 24.6%), and admission blood glucose levels ≥7.0 mmol/L (66.3% v. 33.7%). Compared with patients who survived, who spent a median (interquartile range) of 6 (3 - 10) days in hospital, the median time between admission and death in those who died was 2.5 (1 - 6) days. In multivariate logistic analysis, age ≥55 years, a q-SOFA score ≥2 and a random blood sugar level ≥7.0 mmol/L were predictors of in-hospital mortality, with adjusted odds ratios of 1.54 (95% CI 1.09 - 2.17), 2.17 (95% CI 1.40 - 3.38) and 1.65 (95% CI 1.18 - 2.30), respectively. Raised serum creatinine was not associated with in-hospital COVID-19 mortality after adjusting for other confounders. Conclusions. This study highlights that high in-hospital COVID-19 mortality was associated with a high q-SOFA score, hyperglycaemia on admission and older age. The study reinforces the need to invest in emergency healthcare services for optimal management of COVID-19 patients presenting with high q-SOFA scores in resource-limited countries.