Incidence and factors associated with pulmonary embolism among RT-PCR confirmed Covid-19 patients with upfront CT pulmonary angiography in Ethiopia: A nested case-control study

ABSTRACT

Introduction: Pulmonary embolism is one of the complications of COVID-19, with reported incidence ranging from 3 to 33 % in non-ICU patients to as high as 40% among ICU patients. Since the clinical presentations of COVID-19 and Pulmonary embolism overlap, it is difficult to differentiate between these cases. This study aimed to assess the incidence of pulmonary embolism and associated factors among confirmed Covid-19 Patients in Ethiopia. Methods: A nested case control study was conducted among 131 patients with COVID-19 (40 COVID-19 patients with Pulmonary embolism and 91 COVID-19 patients with no PE) who were on follow up from May, 2021 to May, 2022. Data was summarized using frequencies with percentages. A chi-square test/ Fisher's exact test was run to determine the presence of a significant difference between the exposure variables and the development of PE. To identify factors associated with the development of Pulmonary embolism, a multivariable Binary Logistic Regression model with sensitivity analysis was run. Results: The incidence of PE was 30.5% (95% CI, 22.9% - 37.4%) in the cohort of patients for whom upfront CTPA was performed. The Chi-square/ Fisher's exact test results showed a significantly higher proportion of patients with PE tend to present with shortness of breath, chest pain and anosmia/ageusia than those with no PE. However, in a subsequent regression analysis, only chest pain was found to be significantly associated with the development of PE in COVID-19 patients (AOR= 3.24, 95% CI= 1.10, 9.54, p-value=0.033). Conclusion: The incidence of PE among COVID-19 patients was found to be relatively lower than reports from other countries. Having chest pain was found to be a significant factor that indicates the development of PE, implying that in a setting where performing upfront CTPA is not practical, detailed symptom inquiry could serve as an important clinical criteria.