A recent research paper linked "long COVID," a set of COVID-19-related symptoms that can last weeks or months, to "abnormalities" in multiple organs, including the lungs and kidneys.
The new study, published in The Lancet over the weekend, found there were higher rates of lung, brain, and kidney injuries among those with the condition, compared with the non-COVID-19 control group. Lung injuries, in particular, were about 14 times higher among long COVID patients, and abnormal findings among the kidneys and brain were about two and three times higher, respectively.
While much about long COVID is unknown, some medical researchers say it has symptoms such as brain fog, fatigue, and shortness of breath that can last months after patients first contracted COVID-19.
The findings were part of the Capturing the MultiORgan Effects of COVID-19 study, according to England's University of Oxford. Betty Raman, an associate professor of cardiovascular medicine at the University of Oxford, helped lead the study and said in a release that "nearly one in three patients had an excess burden of multiorgan abnormalities on MRI relative to controls."
“At five months after hospital discharge for COVID-19, patients showed a high burden of abnormalities involving the lungs, brain and kidneys compared to our non-COVID-19 controls," she added in the university's release. “The age of the individual, severity of acute COVID-19 infection, as well as comorbidities, were significant factors in determining who had organ injury at follow-up.”
Dr. Raman added: “In patients without organ-specific comorbidities, the damage may well be due to severe COVID-19 infections ... we think that comorbidities lower the reserve of organs and potentially play a role in delayed recovery, but we see organ abnormalities even in those without comorbidities,” according to the Irish Times.
The findings, based on analysis of more than 250 patients who were hospitalized for COVID-19 in the UK, were recruited across 13 areas across the country, and about 50 people who did not have the virus. They had MRI, or magnetic resonance imaging, scans covering their lungs, heart, brain, and kidneys about five months after leaving the hospital.
"Our findings also highlight the need for longer-term multidisciplinary follow-up services focused on pulmonary and extrapulmonary health (kidneys, brain and mental health), particularly for those hospitalized for COVID-19," Dr. Raman said.
Researchers cautioned that not all symptoms that were observed could be linked to COVID-19. But they noted that damage to several organs was more likely in individuals who contracted the virus, and who had also reported severe physical and mental health issues afterward.
The Oxford researchers also noted that the long COVID group was slightly older in age and generally less healthy than the control group. However, the paper said the researchers tried to adjust their findings to make up for the differences.
“Rather, the interaction of two or more abnormalities in organs might have an additive or multiplicative effect in creating physiological deficits that result in long COVID symptoms,” he wrote.
The study was also conducted between March 1, 2020, and Nov. 1, 2021, coming before later COVID-19 strains such as Omicron emerged. Omicron-derived variants are still the dominant form of COVID-19 throughout the world.