AlBahrani, SalmaAlAhmadi, NayefHamdan, SafaElsheikh , NouraOsman, AssimAlmuthen , SharifahAlmajed , Ghadeer N.Alkhuraim , Arwa H.Jebakumar, Arulanantham ZechariahAl-Tawfiq, Jaffar A.2024-06-202024-06-202022-05AlBahrani, S., AlAhmadi, N., Hamdan, S., Elsheikh, N., Osman, A., Almuthen, S., Almajed, G. N., Alkhuraim, A. H., Jebakumar, A. Z., & Al-Tawfiq, J. A. (2022). Clinical Presentation and Outcome of Hospitalized Patients With COVID-19 in the First and Second Waves in Saudi Arabia. International Journal of Infectious Diseases, 118, 104–108. https://doi.org/10.1016/j.ijid.2022.02.048https://hdl.handle.net/1805/41657Introduction The world had witnessed the occurrence of multiple waves of the SARS-CoV-2. Data comparing the clinical characteristics and outcomes of hospitalized patients in Saudi Arabia during the first and second waves are lacking. This study compares the characteristics and the outcomes of patients in these 2 waves. Methods This is a retrospective case series of hospitalized patients with confirmed SARS-CoV-2. We compared epidemiological, demographic, laboratory, and clinical data. Results The study included hospitalized patients admitted up to February 28, 2021 as the first wave and those admitted from March 1, 2021 as the second wave. There were 378 patients in the first wave and 241 patients in the second wave. Patients in the first wave were significantly younger (mean age and SD of 47.5 ± 20 vs 55.3 ± 18.2 years; p <0.001). In relation to symptoms, shortness of breath, wheezes, myalgia, tachypnea, and respiratory distress were significantly more common in the second wave than the first wave. On the other hand, sore throat was more common in the first wave than the second wave. Patients in the second wave had higher mean values of lymphocytes count, platelet counts, and ALT than those in the first wave. Patients in the first wave were more likely to receive antibiotics and antiviral therapy and had higher death rate (16.2% vs 8.4%; p = 0.001). Conclusion The study showed that patients in the second wave were younger and had a lower rate of death than the first wave.en-USAttribution-NonCommercial-NoDerivatives 4.0 InternationalSARS-CoV-2COVID-19WavesVariantsArticle