Harlan Krumholz, a cardiologist at the Yale School of Medicine, says he worries about two kinds of long covid. The obvious version induces fatigue, while a stealthier version involves higher risk of blood clots and strokes after a covid recovery. He doesn’t want to panic people. Most of us will probably be fine. But new studies confirm that some will develop an elevated risk of blood clots, strokes or heart attacks.
Scary reports began to surface in 2020 of young people suffering strokes during or right after infection. Doctors were starting to suspect covid was not just a respiratory disease but a blood vessel one. Studies now back up their suspicions. Patients with high blood pressure or diabetes have had their high risk go even higher. One recent study, published in Heart, tracked 54,000 people in the UK and concluded that those who’d been infected were 2.7 times more likely to develop venous thromboembolism, a dangerous type of blood clot, than those who had never been infected.
The study also showed that those who got infected but were not sick enough to be hospitalized were still 10 times more likely to die of any cause during the study period of 4.5 months than their uninfected counterparts. People who’d been hospitalized for covid were about 100 times more likely to die.
Krumholz said we still don’t have enough data to know how much these risks are mitigated by vaccination or how long the elevated risk lasts. That viruses can have lingering effects was known, but until the Sars-CoV-2 pandemic, it had never been studied so thoroughly. A consensus is forming that the lasting damage is caused by inflammation—a necessary part of our immune defense system, but one that can cause harm if it stays in high gear.
A Roll Of The Dice
Not everyone who gets covid will suffer serious blood vessel inflammation, but the disease is still something of a roll of the dice—or, as physician Ziyad Al-Aly puts it, Russian Roulette. That doesn’t mean people should despair or panic. Early treatment can save lives, which is why doctors urge people who’ve been infected not to ignore any warning sign. Al-Aly was one of the first doctors to jump into studying long covid. “Something about Sars-CoV-2 increases propensity to damaging the lining of the blood vessels and increases the probability of blood clotting,” he said.
“What makes this such a dangerous disease is mainly that it attacks these vessels,” said Pascal Jabbour, a neurosurgeon at Thomas Jefferson Hospital, Philadelphia. The disease can lead to inflammation in blood vessels all over the body, including the gut, causing a condition called bowel ischemia. It’s also at the root of a circulatory problem known as covid toes. Jabbour is lead author of the Neurosurgery paper.
Some in the infected group had mild infections, and a few didn’t know they had covid until they showed up at the hospital with a stroke, Jabbour said. This further complicates the already complex task of tallying covid deaths. Should people who appear to have died of a stroke and tested positive be counted as dying with covid or from covid?
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