There’s little doubt long COVID is real. The federal government recognizes long COVID as a condition and said in two reports issued in August that one in five adult COVID-19 survivors have a health condition related to their illness.
COVID-19 can damage multiple organs in the body. Sometimes this damage leads to long COVID; sometimes other reasons are at play. Doctors are beginning to sort it out.
“COVID itself can actually cause prolonged illness, and we don’t really call that long COVID,” said Nisha Viswanathan, MD, a doctor at UCLA Health in Los Angeles. But if symptoms extend beyond 12 weeks, that puts patients in the realm of long COVID.
Symptoms can range from mild to severe and can keep people from resuming their normal lives and jobs. Sometimes they last for months, according to the U.S. Department of Health & Human Services.
Multiorgan damage
Lung scarring and other lung problems are common after COVID, said Leora Horwitz, MD, an internal medicine specialist at New York University. Even after a mild case, people can have breathing issues for months, a team at Johns Hopkins Medicine, Baltimore, said in an online briefing. One study published in the journal Radiology found damage in people a full year after a COVID-19 diagnosis.
Some people have persistent heart, kidney, liver, and nervous system problems after COVID-19. A study published in 2020 in JAMA Cardiology found 60% of people who had COVID-19 had ongoing signs of heart inflammation. Nearly a third of people hospitalized for COVID-19 get kidney damage that can become chronic, and some end up needing dialysis or a transplant, said C. John Sperati, MD, a kidney specialist at Johns Hopkins Medicine.
This might be, in part, because SARS-CoV-2, the virus that causes COVID-19, directly infects the cells in many organs.
Nicole Bhave, MD, a cardiologist at University of Michigan Health, Ann Arbor is concerned that COVID-19 appears to increase the risk of heart problems in some people.
“Some of the uptick may just be recognition bias, in that people with symptoms are seeking care,” she said. “But there’s definitely a biological basis by which COVID could tip people over into a new diagnosis of heart failure.”
Inflammation
Inflammation is probably a key part of the long-term effects of COVID-19.
Some people have a serious immune reaction to COVID-19 called a cytokine storm, said Nitra Aggarwal Gilotra, MD, a cardiologist at Johns Hopkins Medicine. This release of inflammation-causing molecules called cytokines is meant to attack the invading virus. But it can be so severe that it wreaks havoc on healthy tissues and organs and causes lasting damage – if patients even survive it.
In some people, inflammation can affect the heart, causing myocarditis. Myocarditis symptoms include chest pain, breathlessness, and heart palpitations. Though rare, it can be serious and can raise the risk of other heart problems, including heart failure, down the line.
Long COVID may also trigger an autoimmune condition, said Eline Luning Prak, MD, PhD, a pathologist at the Hospital of the University of Pennsylvania, Philadelphia. Long COVID can share many hallmark symptoms with autoimmune diseases, including fatigue, widespread pain, memory problems, and mood disorders.