Study population:
The current case-control study has been conducted on 243 patients admitted at Amin and Alzahra Hospitals (affiliated at Isfahan University of Medical Sciences) due to SARS-CoV-2 from May to June 2020. The included patient consisted of 83 cases with thrombotic events and 160 ones as controls with no thrombotic event, matched according to presence of COVID-19 pneumonia.
The study proposal was provided to the Ethics Committee of Isfahan University of Medical Sciences and approved by IR.MUI.MED.REC.1399.692 code number. After that, the study protocol was explained to the patients, if possible, or their legal guardians; they were reassured about the confidentiality of the obtained information and requested to sign written consent for participation in the study.
The case group was selected from the patients with any thrombotic event, including deep vein thrombosis (DVT), ischemic cerebrovascular accidents (CVA), pulmonary thromboembolism (PTE), or myocardial infarction (MI) whose COVID-19 infection was approved by a positive polymerase chain reaction (PCR) test and signs of COVID-19 pneumonia was present in the imaging. The inclusion of the patients was done using a convenience sampling.
Also all patients in the control group had positive result for PCR test and radiographic signs of COVID-19 pneumonia, but with no thrombotic event. The control group was matched to the cases with a 2: 1 proportion.
The previous history of coagulopathies and a recent history of thrombotic events (DVT, PTE, CVA, or AMI) within a month prior to the hospital admission were determined as the exclusion criteria.