Risks of deep vein thrombosis, pulmonary embolism, and bleeding after covid-19: nationwide self-controlled cases series..., 2022, Katsoularis et al

Full title: Risks of deep vein thrombosis, pulmonary embolism, and bleeding after covid-19: nationwide self-controlled cases series and matched cohort study

Abstract

Objective To quantify the risk of deep vein thrombosis, pulmonary embolism, and bleeding after covid-19.

Design Self-controlled case series and matched cohort study.

Setting National registries in Sweden.

Participants 1 057 174 people who tested positive for SARS-CoV-2 between 1 February 2020 and 25 May 2021 in Sweden, matched on age, sex, and county of residence to 4 076 342 control participants.

Main outcomes measures Self-controlled case series and conditional Poisson regression were used to determine the incidence rate ratio and risk ratio with corresponding 95% confidence intervals for a first deep vein thrombosis, pulmonary embolism, or bleeding event. In the self-controlled case series, the incidence rate ratios for first time outcomes after covid-19 were determined using set time intervals and the spline model. The risk ratios for first time and all events were determined during days 1-30 after covid-19 or index date using the matched cohort study, and adjusting for potential confounders (comorbidities, cancer, surgery, long term anticoagulation treatment, previous venous thromboembolism, or previous bleeding event).

Results Compared with the control period, incidence rate ratios were significantly increased 70 days after covid-19 for deep vein thrombosis, 110 days for pulmonary embolism, and 60 days for bleeding. In particular, incidence rate ratios for a first pulmonary embolism were 36.17 (95% confidence interval 31.55 to 41.47) during the first week after covid-19 and 46.40 (40.61 to 53.02) during the second week. Incidence rate ratios during days 1-30 after covid-19 were 5.90 (5.12 to 6.80) for deep vein thrombosis, 31.59 (27.99 to 35.63) for pulmonary embolism, and 2.48 (2.30 to 2.68) for bleeding. Similarly, the risk ratios during days 1-30 after covid-19 were 4.98 (4.96 to 5.01) for deep vein thrombosis, 33.05 (32.8 to 33.3) for pulmonary embolism, and 1.88 (1.71 to 2.07) for bleeding, after adjusting for the effect of potential confounders. The rate ratios were highest in patients with critical covid-19 and highest during the first pandemic wave in Sweden compared with the second and third waves. In the same period, the absolute risk among patients with covid-19 was 0.039% (401 events) for deep vein thrombosis, 0.17% (1761 events) for pulmonary embolism, and 0.101% (1002 events) for bleeding.

Conclusions The findings of this study suggest that covid-19 is a risk factor for deep vein thrombosis, pulmonary embolism, and bleeding. These results could impact recommendations on diagnostic and prophylactic strategies against venous thromboembolism after covid-19.

Open access, https://www.bmj.com/content/377/bmj-2021-069590

 

Covid linked to 33-fold increase in risk of potentially fatal blood clot

"Catching Covid is associated with a fivefold increase in the risk of deep vein thrombosis (DVT) and a 33-fold increase in risk of a potentially fatal blood clot on the lung in the 30 days after becoming infected, data suggests.

The findings, published in the British Medical Journal on Thursday, could help explain a doubling in the incidence of, and deaths from, blood clots in England since the start of the pandemic compared with the same periods in 2018 and 2019.

They also help to put the very small increased risk of blood clots associated with Covid-19 vaccination into context. “The degree of complications associated with Covid-19 is much stronger and lasts for much longer than what we might be getting after vaccination,” said Dr Frederick Ho, a lecturer in public health at the University of Glasgow, who was not involved in the research."

https://www.theguardian.com/world/2...-33-fold-increase-risk-pulmonary-embolism-dvt