question: INTRODUCTION: The first documented case of COVID-19 in Kenya was recorded March of 2020. Co-morbidities including hypertension and diabetes have been associated with increased morbidity, hospitalization, and mortality among COVID-19 patients. This retrospective study describes the clinical characteristics, disease severity, and outcomes among the patient population at a tertiary hospital in Kenya. METHODS: This was a retrospective descriptive study of COVID-19 patients who were admitted between March 2020 and December 2020 at the Aga Khan University Hospital in Nairobi, Kenya. Data collected include patient demographic and baseline characteristics. Differences between patients who were known to have diabetes and hypertension during admission were compared for statistical significance. Difference between those who survived and those who died were also compared for statistical significance. RESULTS: A total of 913 records of patients were studied with a mean age of 51.2 years (SD = 16.7), 66.5% were male and 80.8% were of African origin. History of diabetes, hypertension, and HIV status were at 27.3%, 33.1%, and 2.3%, respectively. At presentation, 33.1% (302/913) of patients had known hypertension by history, and following admission, this proportion increased to 37.7% (344/913). At presentation, 27.3% (249/913) of patients had known diabetes. During hospital stay, 20.8% (190) more patients were found to have diabetes, raising the overall percent to 48.1% (439/913). When comparing diabetes and hypertension at baseline versus at the end of admission, diabetes increased by 20.8% (p < 0.001) and hypertension by 4.6% (p = 0.049). HIV co-infection was 2.3%, and no patient had tuberculosis. CONCLUSION: This study showed a high incidence of co-morbidities in patients infected with COVID-19. Diabetes was most common, followed by hypertension. All patients admitted with COVID-19 infection should routinely be tested for diabetes with HbA1c and have regular blood pressure monitoring in order to diagnose occult diabetes and hypertension. Adverse outcomes were found in patients with these co-morbidities and should be monitored and treated appropriately.