London, Apr 7: People infected with SARS-CoV-2, the virus that causes COVID-19, have an increased risk of developing serious blood clots for up to six months after the infection, even in mild cases, according to a study published in The BMJ.
The researchers found an increased risk of deep vein thrombosis -- a blood clot in the leg -- up to three months after COVID-19 infection, pulmonary embolism -- a blood clot in the lung -- up to six months, and a bleeding event up to two months.
They also show a higher risk of events in patients with underlying conditions, patients with more severe COVID-19, and during the first pandemic wave compared with the second and third waves.
The researchers from Umea University in Sweden noted that these results support measures to prevent thrombotic events, especially for high risk patients, and strengthen the importance of vaccination against COVID-19.
Using national registries in Sweden, they identified more than one million people with confirmed SARSCoV-2 infection between February 1, 2020 and May 25, 2021, matched by age, sex, and county of residence to more than four million people who had not had a positive SARS-CoV-2 test result.
The researchers first calculated the rates of deep vein thrombosis, pulmonary embolism, and bleeding in COVID-19 individuals during a control period -- before and long after COVID-19 diagnosis -- and compared it to the rates in different time intervals after COVID-19 diagnosis.
They then calculated the rates of deep vein thrombosis, pulmonary embolism, and bleeding 1-30 days after COVID-19 diagnosis in the COVID-19 group and compared them to the corresponding rates in the control group.
The results show that compared with the control period, risks were significantly increased 90 days after COVID-19 for deep vein thrombosis, 180 days for pulmonary embolism, and 60 days for bleeding.
After taking account of a range of potentially influential factors, the researchers found a five-fold increase in risk of deep vein thrombosis, a 33-fold increase in risk of pulmonary embolism, and an almost twofold increase in risk of bleeding in the 30 days after infection.
This means that a first deep vein thrombosis occurred in 401 patients with COVID-19 and 267 control patients, the researchers said.
A first pulmonary embolism event occurred in 1,761 patients with COVID-19 and 171 control patients, and a first bleeding event occurred in 1,002 patients with covid-19 and 1,292 control patients, they said.
The researchers found that the risks were highest in patients with more severe COVID-19 and during the first pandemic wave compared with the second and third waves, which they said could be explained by improvements in treatment and vaccine coverage in older patients after the first wave.
Even among mild, non-hospitalised COVID-19 patients, the researchers found increased risks of deep vein thrombosis and pulmonary embolism.
No increased risk of bleeding was found in mild cases, but a noticeable increase was observed in more severe cases.
This is an observational study, so the researchers cannot establish cause, and they acknowledge several limitations which might have affected their findings.
For example, they said VTE may have been underdiagnosed in patients with COVID-19, testing for the disease was limited, especially during the first pandemic wave, and information on vaccination was not available.
Let the Truth be known. If you read VB and like VB, please be a VB Supporter and Help us deliver the Truth to one and all.
Panaji (PTI): As part of a crackdown against tourist establishments violating laws and safety norms in the aftermath of the Arpora fire tragedy, Goa authorities on Saturday sealed a renowned club at Vagator and revoked the fire department NOC of another club.
Cafe CO2 Goa, located on a cliff overlooking the Arabian Sea at Vagator beach in North Goa, was sealed. The move came two days after Goya Club, also in Vagator, was shut down for alleged violations of rules.
Elsewhere, campaigning for local body polls, AAP leader Arvind Kejriwal said the fire incident at Birch by Romeo Lane nightclub at Arpora, which claimed 25 lives on December 6, happened because the BJP government in the state was corrupt.
An inspection of Cafe CO2 Goa by a state government-appointed team revealed that the establishment, with a seating capacity of 250, did not possess a no-objection certificate (NOC) of the Fire and Emergency Services Department. The club, which sits atop Ozrant Cliff, also did not have structural stability, the team found.
The Fire and Emergency Services on Saturday also revoked the NOC issued to Diaz Pool Club and Bar at Anjuna as the fire extinguishers installed in the establishment were found to be inadequate, said divisional fire officer Shripad Gawas.
A notice was issued to Nitin Wadhwa, the partner of the club, he said in the order.
Campaigning at Chimbel village near Panaji in support of his party's Zilla Panchayat election candidate, Aam Aadmi Party leader Kejriwal said the nightclub fire at Arpora happened because of the "corruption of the Pramod Sawant-led state government."
"Why this fire incident happened? I read in the newspapers that the nightclub had no occupancy certificate, no building licence, no excise licence, no construction licence or trade licence. The entire club was illegal but still it was going on," he said.
"How could it go on? Couldn't Pramod Sawant or anyone else see it? I was told that hafta (bribe) was being paid," the former Delhi chief minister said.
A person can not work without bribing officials in the coastal state, Kejriwal said, alleging that officers, MLAs and even ministers are accepting bribes.
