Factors associated with mortality among patients aged 12 years and above requiring hospitalization for severe respiratory illness (SRI): Findings from the COVID-19 vaccine effectiveness evaluation in Kenya and Mali, 2022–2023

Background: Mortality attributed to respiratory illnesses is well characterized in children <5 years. However, there is paucity of data among older populations. Here, we leveraged data from the COVID-19 Vaccine Effectiveness Evaluation to establish the factors associated with mortality among patients with severe respiratory illness (SRI) in Kenya and Mali. Methods: We enrolled patients (≥ 12 years) requiring hospitalization for SRI, defined as acute onset (≤ 14 days) of at least two of the following: cough, fever (reported/measured temperature of ≥38 °C), chills, rigors, myalgia, headache, sore throat, fatigue, congestion or runny nose, loss of taste or smell, or pneumonia diagnosis, from referral hospitals in Kenya and Mali. We collected demographic, clinical characteristics of the patients, and nasopharyngeal and oropharyngeal specimens for SARS-CoV-2 testing using RT-PCR. A mixed-effects logistic regression model was fitted to identify factors associated with 30-day mortality among patients with SRI. Results: Between July 2022 and October 2023 9947 SRI patients were enrolled, of whom 9743 were included in this analysis and 1620 (16.6 %) died (Kenya: 1533/7822 [20.0 %]; Mali: 87/1921 [4.5 %]). Compared to patients aged 12–24 years, those aged >64 years were more likely to die (adjusted Odds Ratio [aOR] = 2.36; 95 % Confidence Interval [95 % CI] 1.72–3.24). Patients who were in coma (aOR = 3.45; 95 %CI 2.27–5.24) or Intensive Care Unit (aOR = 2.98; 95 %CI 2.06–4.31), or had HIV infection (aOR = 2.47; 95 %CI 2.11–2.90), liver disease (aOR = 2.42; 95 %CI 1.57–3.74), cancer (aOR = 2.09; 95 %CI 1.46–2.99) or SARS-CoV-2 infected (aOR = 1.24; 95 %CI 1.02–1.52) were at increased risk of death. Additionally, diarrhea, malaise/fatigue, difficulty in breathing, confusion, mechanical ventilation, vasopressor support, malnutrition and admission to High Dependency Unit had significant associations. Conclusion: Mortality was heightened among SRI patients who were older, required critical care, had chronic conditions and infected with SARS-CoV-2 suggesting need for early identification of these conditions to improve possible treatment outcomes.