Difference in presentation, outcomes, and hospital epidemiologic trend of COVID-19 among first, second, and third waves in Dhaka Medical College

Background This study aimed to examine the differences in epidemiologic and disease aspects among patients with COVID-19 Methods We reviewed the hospital records between April 2020 and September 2021 and followed up on the patients for post-COVID complications. Findings Older adult patients were predominantly affected during the first and second waves, followed by middle-aged patients. Men were predominantly admitted, considering the three waves; although more women were admitted in the second wave. Cough was more common in the second and third waves than in the first wave 522 (59.7%). Respiratory distress was the most common in the third wave, 251(67.1%), and least common in the first wave 403 (46.1%). Anosmia was more common in the third wave 116 (31.2%). In the third wave, patients presenting in a critical state 23 (6.2%) and severe disease 152 (40.8%) were more common. The hospital admission median (IQR) was longer in the first wave, 12 (8–20), than in other waves. More patients were admitted in the first wave (52%) than in the other waves, and patients received more oxygen in the third wave (75%) than in the other waves. Death occurred more commonly in the first wave (51%) than in the other waves. Patients were investigated more commonly in the first and third waves than in the second wave. The positivity rate was high in the third wave (22.8%) than in other waves. In the third wave, the positivity rate was higher in women (24.3%) than in men. Post-covid cough increased in the second wave and fatigue was higher in the third wave than in other waves. Tiredness and memory loss was greater during the second wave than in other waves. Conclusion This study revealed that the presenting symptoms, outcomes, and epidemiologic trends differed during the COVID-19 waves. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was funded by Directorate General of Health, Bangladesh ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Institutional Ethical Committee of Dhaka Medical College approved the study (ERC-DMC/ECC/2021/55). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors