Mortality and Change in the Prevalence of Deep Vein Thrombosis Associated With SARS-CoV-2 P.1 Variant.

Background and objective Thrombosis is one of the significant challenges associated with cardiovascular diseases and a prominent cause of death globally. This study aimed to determine the monthly and overall mortality rates by sex and age group in patients hospitalized with coronavirus disease 2019 (COVID-19) and the prevalence of deep vein thrombosis (DVT) in those patients. We also investigated whether the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) P.1 variant influenced DVT. Methods We determined the overall prevalence of COVID-19 per sex, age, and monthly mortality using hospital data at the São José do Rio Preto School of Medicine, state of São Paulo, Brazil. Data of COVID-19 patients with DVT as determined by echo-Doppler ultrasound (EDU) were analyzed by taking two time periods into account (prior to and after the onset of the predominance of the SARS-CoV-2 P.1 variant) to evaluate whether the viral variant exerted an influence on the prevalence of DVT. Patients with COVID-19 but without DVT comprised the control group. The first period was from March 2020 to February 2021, and the second was from March to June 2021. Results Between March 2020 and June 2021, 6,199 patients were hospitalized with COVID-19 at our institution. Of these, 2,805 (45.25%) were women and 3,376 (54.47%) were men. Two hundred fifty-four were diagnosed with DVT based on lower limb EDU. The mean mortality rate was significantly associated with sex (38.36% for men and 27.16% for women; p=0.01). The incidence of DVT in patients with COVID-19 rose significantly from 1.6% during the first study period to 7.7% during the second study period (p=0.0001), when the P.1 variant became the predominant strain. The mortality rate was significantly higher in patients with COVID-19 and DVT (58.1%) compared to the control group (33.6%; p=0.0001). Conclusion Based on our findings, the incidence and prevalence of DVT increased with the predominance of P.1. viral variant. Early diagnosis and the reassessment of prophylaxis are the two most important factors to be addressed in this patient population.