Neurological symptoms are extremely common among Covid-19 patients sick enough to be hospitalized, according to a study released Monday.
Symptoms range from mild to severe and can include headaches, dizziness, and impaired brain function, according to the study in the Annals of Clinical and Translational Neurology.
Full coverage of the coronavirus outbreak
The findings highlight the far-reaching effects the virus can have on the body. Furthermore, the study found that patients can continue to experience these symptoms long after they recover from the disease.
The news comes when President Donald Trump was supposed to leave Walter Reed National Military Medical Center after being hospitalized for three days. His doctors did not indicate that the president exhibited any major neurological symptoms.
In the study, researchers from Northwestern Medicine looked at the top 509 patients admitted within their network of 10 hospitals and medical centers in Chicago in March and April. Just over a quarter had been put on fans.
The majority of the 509 patients – 82% – developed problems arising from the nervous system. “This means that 4 out of 5 patients admitted to our hospital system at the onset of the pandemic had these neurological problems,” said Dr. Igor Koralnik, study co-author and head of neuroinfectious diseases and global neurology at Northwestern Medicinale.
Muscle pain was reported by nearly 44.8% of patients and 37.7% complained of headaches.
Just under a third of patients developed a more severe type of neurological problem: encephalopathy or impaired brain function.
The problems ranged from mild symptoms, such as difficulty paying attention, short-term memory, concentration and multitasking skills, “to confusion, stupor and coma,” Koralnik said. More severe brain function problems were more likely in older patients over the age of 65.
Others have reported feeling dizzy or losing their sense of taste or smell.
“This confirms that neurological manifestations are common, but often mild. This is important,” said Mayo Clinic neurologist Dr. Alejandro Rabinstein. “Many patients in hospital with Covid will have muscle pain, will have loss of smell and taste. Those are reversible and benign.” Rabinstein was not involved in the new study.
It appears that the symptoms were not the result of hospitalization, which can occur after patients have been treated in the intensive care unit, but rather the virus itself. Forty-two percent of the patients in the study had neurological problems when they first fell ill.
Indeed, Koralnik said such problems could be the first signs of a coronavirus infection. People who suddenly can’t smell, without explanation, “should consider it as a sign of the first Covid-19”.
“They should be tested faster and quarantine and track their contacts to prevent further spread” of the virus, “he added.
Download the NBC News app for the latest president health news
Future studies on patients hospitalized with Covid-19 could reveal different impacts on the nervous system. This research has focused on patients admitted to hospital early in the pandemic, usually in dedicated Covid-19 wards without extensive access to brain imaging. Additionally, less than 6% of the patients in this study were seen by neurologists or neurosurgeons.
“Just nine months into the pandemic”, the study authors wrote, “the long-term effects of Covid-19 on the nervous system remain uncertain.”
The long-term effects of these symptoms are also unknown. Koralnik and his colleagues will continue to follow patients after they leave the hospital, including so-called long-haul transporters, who continue to experience symptoms, such as fever, fatigue and brain fog, months after they recover from the virus.
“It’s important for people to realize the extent of these problems,” said Koralnik, who also oversees the Northwestern Medicine Neuro Covid-19 research group. “We need to keep doing more research to try to find out why this is happening, particularly brain fog.”
Follow NBC HEALTH on Twitter & Facebook.