One recent study has found some symptoms of long COVID-19 may be related to nerve damage, and another identified the proportion of patients who require new healthcare services upon discharge from being hospitalized for COVID-19.
A small study published March 1 in Neurology Neuroimmunology and Neuroinflammation involving 17 participants suggests long-term nerve damage may be behind some patients' long COVID-19 symptoms, such as brain fog. The study, led by researchers at Boston-based Massachusetts General Hospital, found evidence of peripheral neuropathy — nerve damage that causes weakness and pain in the hands and feet and can be triggered by infection — in 10 of the participants, or 59 percent.
"What we asked is, could some of what's going on with long-haul COVID-19 actually reflect undiagnosed peripheral neuropathy?" Anne Louise Oaklander, MD, PhD, study author and associate professor of neurology at Harvard Medical School, told NBC News, adding the results indicated small-fiber neuropathy, or damage to peripheral nerve fibers, was the most common form.
"That's really point one: We found a real objective medical problem in over half of these patients," Dr. Oaklander said, emphasizing the results are based on a small, "biased data set," as some participants in the study were already believed to have a neurological condition. The findings offer clues about potential avenues for treatment, as peripheral neuropathy has an established medical framework with treatment options upon diagnosis — unlike long COVID-19.
Still, experts say the neurological diagnosis will not be something that fits all long COVID-19 patients. "To me, the next question is, how common is this? Is this a big deal that is a complete breakthrough, or is this going to end up affecting 1 percent of patients?" Dr. Oaklander said. "I cannot give you one answer either way."
A separate study, published March 1 in the American Journal of Critical Care, found nearly 1 in 4 COVID-19 survivors who were hospitalized required new at-home or facility-based healthcares services upon discharge. The study involved 1,480 adult patients hospitalized for COVID-19 between March 1 to April 1, 2020, across 57 U.S. hospitals.
Overall hospital mortality was nearly 18 percent. The study also found that severe illness and death were often the result of multiorgan dysfunction rather than isolated respiratory failure.
"Our findings suggest that efforts to reduce severe illness should consider the multiorgan effects of SARS-CoV-2 infection," said Ithan Peltan, MD, lead study author and pulmonologist at Intermountain Medical Center in Murray, Utah.