Effects of the COVID-19 Pandemic on Hospital Admissions and Inpatient Mortality in Kenya: A Retrospective Cohort Study

Background: The impact of COVID-19 in Africa remains poorly described. We studied trends in hospitalisation due to all medical causes, clinician-diagnosed pneumonia admissions, and inpatient mortality in Kenya before and during the first six waves of the COVID-19 pandemic in Kenya.Methods: We conducted a hospital-based observational study of patients admitted to 13 public referral facilities in Kenya from January 2018 to December 2022. The pre-COVID-19 population included patients admitted before 1 March 2020. We fitted time series models adjusted for seasonality and hospital to compare observed and predicted trends for each outcome. To estimate the impact of the COVID-19 pandemic, we calculated incidence rate ratios (IRR) and corresponding 95% confidence intervals (CI) from negative binomial mixed-effects models.Findings: 357,631 patients were admitted across the 13 surveillance sites (range 15,354 to 67,241 per site). 45,349 patients (42·1%) were admitted to the adult medical wards. On the paediatric ward, 163,608 individuals (47 4%) were aged under five years and 36,227 individuals (10 5%) were aged five years and older. In comparison to the pre-COVID period, there was a reduction in hospitalisations for adults (IRR 0 75, 95% CI 0 69 to 0 82) and paediatric cases (IRR 0 69, 95% CI 0 64 to 0 75). In-hospital deaths also declined among both adult (IRR 0 83, 95% CI 0 77 to 0 89) and paediatric (IRR 0 85, 95% CI 0 77 to 0 94) admissions. Pneumonia-specific admissions among adults showed a modest increase during the pandemic (IRR 1 59, 95% CI 1 36 to 1 85) but remained a low proportion of all cases admitted. Paediatric pneumonia cases were lower than pre-pandemic levels in the first year of the pandemic (IRR 0 78, 95% CI 0 51 to 1 20) but then became elevated in late 2021 compared to pre-pandemic period.Interpretation: The COVID-19 pandemic did not cause a surge in hospitalisations in Kenya. However, pneumonia admissions among adults (but not children) increased significantly, with peaks aligning with the pandemic waves. These findings underscore the importance of syndromic inpatient surveillance in detecting and monitoring outbreaks.Funding: This project was funded by the Wellcome Trust (grants 20991/Z/20/Z and 203077/Z/16/Z), The Bill & Melinda Gates Foundation (OPP1131320), and a DFID/MRC/NIHR/Wellcome Trust Joint Global Health Trials Award (MR/R006083/1). This UK-funded award is part of the EDCTP2 programme supported by the European Union.Declaration of Interest: We declare no competing interests.Ethical Approval: Kenya Medical Research Institute (KEMRI) Scientific and Ethics Review Unit approved the study.