Introduction: Using peripheral oxygen saturation (SpO2) measurement is a cost-effective and reliable approach to assess the need for oxygen supplementation in patients admitted with coronavirus disease 2019 (COVID-19). Patients who have a SpO2 level of <95% are considered hypoxic and, per COVID-19 management guidelines, should receive oxygen supplementation. We sought to determine whether hypoxia at admission predicted adverse COVID-19 outcomes including mortality among patients admitted with COVID-19 disease in Kenya. Methods: The study was a cross-sectional retrospective medical chart review of patients hospitalized with COVID-19 between October 1, 2020, and December 31, 2021 in three purposively selected health facilities in Kilifi, Nairobi and Kisumu. We explored the differences in proportions of categorical variables using the χ2 test and assessed predictors (selected a priori) of mortality among patients with hypoxia using Cox proportional hazards models. Using the Kaplan-Meier method, we also computed survival probabilities by hypoxia status for patients on room air or oxygen supplementation and produced survival graphs. Results: Of the 1,124 COVID-19 patients, 94.8% had documented SpO2 measurements at admission, and 81.4% were found to have hypoxia, with 39.9% of hypoxic patients not exhibiting dyspnea. Hypoxic patients compared to those with normal oxygen saturation levels were significantly older (60+ years: 44.6 vs. 24.4%) and had a higher prevalence of dyspnea (60.1 vs. 36.9%), higher pulse rate (38.2 vs. 24.6%), and hypertension (40.4 vs. 25.8%), p<0.001. Oxygen supplementation was provided to only 68.6% of hypoxic patients. Mortality was notably higher in hypoxic patients versus those with normal SpO2 (38.0% vs. 13.6%, p<0.001), with hypoxia being a key predictor of death. Hypoxic, older patients (≥60 years), and those with dyspnea had a higher risk of death (adjusted hazard ratio: 1.9 [95% confidence interval (CI):1.2–2.8], 1.8 [95% CI 1.3-2.6] and 1.5 [95% CI 1.2-2.0], respectively). Regardless of dyspnea or oxygen supplementation, survival probabilities were worse for hypoxic patients (p<0.001). Conclusions: Hypoxia was prevalent among hospitalized COVID-19 patients, even without respiratory distress symptoms. These findings underscore the importance early identification and management of hypoxia in COVID-19 patients, thereby guiding clinical care and improving outcomes, particularly for older or sicker patients.

The authors have declared no competing interest.

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This activity was reviewed by CDC, deemed not research, and was conducted consistent with applicable federal law and CDC policy.* It was also reviewed by the University of California San Fransico’s Institutional Review Board (UCSF-22-37353) and AMREF’s Ethical and Scientific Review Committee (AMREF-ESRC P1233/2022), the University of California, San Francisco Human Research Protection Program Institutional Review Board (IRB approval number 22-37353), and ethical review committees from the three participating hospitals. The Kenya National Commission for Science, Technology, and Innovation (NACOSTI) permitted this study (License No: NACOSTI/P/22/19903). Due to the study’s retrospective nature and the use of de-identified data, the requirement for individual patient consent was waived. *45 C.F.R. part 46.102(l)(2), 21 C.F.R. part 56 42 U.S.C. Sect. 241(d) 5 U.S.C. Sect. 552a 44 U.S.C. Sect. 3501 et seq.

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The data underlying the results presented in the study are available from the head Division of Disease Surveillance and Response, email: [contact authors]