Immediate and Contributory Causes of Death in Patients Hospitalized with Covid-19

ABSTRACT

Background: Accurate determination of the immediate and contributory causes of death in patients with COVID-19 is important for optimal care and instituting mitigation strategies. Method(s) All deaths in Qatar between March 1, 2020 and August 31, 2022 flagged for likely relationship to COVID-19 by were evaluated by two independent reviewers trained to determine and assign the most likely immediate underlying cause of death. Each decedent's electronic medical records was comprehensively reviewed, and the cause of death was assigned based on the most plausible underlying event that triggered the event(s) that led to death based on clinical documentation and a review of laboratory, microbiology, pathology, and radiology data. After cause assignment, each case was categorized into major diagnostic groups by organ system, syndrome, or disease classification. Result(s) Among 749 deaths flagged for likely association with COVID-19, the most common admitting diagnoses were respiratory tract infection (91%) and major adverse cardiac event (MACE, 2.3%). The most common immediate cause of death was COVID pneumonia (66.2%), followed by MACE (7.1%), hospital associated pneumonia (HAP, 6.8%), bacteremia (6.3%), disseminated fungal infection (DFI, 5.2%), and thromboembolism (4.5%). The median length of hospital stay was 23 days (IQR 14,38). COVID pneumonia remained the predominant cause irrespective of the time from admission, though the proportion dropped with increasing length of stay in the hospital. Other than COVID pneumonia, MACE was the predominant cause of death in first two weeks but declined thereafter. No death occurred due to bacteremia, HAP, or DFI in the first week after hospitalization, but became increasing common with increased length of stay in the hospital accounting for 9%, 12%, and 10% of all deaths after 4 weeks in the hospital respectively. The majority of deaths (86%) occurred in the intensive care unit setting. COVID pneumonia accounted for approximately two-thirds of deaths in each setting. MACE and HAP were approximately equally represented in both settings while bacteremia and disseminated fungal infection were more common in the intensive care unit setting. Conclusion(s) Nearly one-third of patients with COVID infection die of non- COVID causes, some of which are preventable. Mitigation strategies should be instituted to reduce the risk of such deaths. (Figure Presented).