Video: “Chicago Tonight” discusses the study with Dr. Edith Graham, a Northwestern Medicine neurologist and co-author of the study; and Eddie Palacios, a COVID-19 patient who participated in the study. (Produced by Nick Blumberg)

Weeks after recovering from COVID-19, some patients continue to experience symptoms such as headaches, dizziness, “brain fog,” fatigue and muscle pain. 

They are often referred to as long haulers. To help them, Northwestern Medicine opened a clinic last May to treat patients if they were diagnosed with COVID-19 or experienced symptoms of the virus.

A new Northwestern Medicine study of 100 long haulers, who were not hospitalized and only experienced mild symptoms like sore throat, fever and cough, found that 85% experienced four or more neurologic symptoms, including “brain fog,” that impacted their quality of life and, in some cases, their cognitive abilities.

“The report (found symptoms) impeded the quality of life for cognition and fatigue. Some patients also tested worse than average compared to their demographics for standardized tests for attention and working memory,” said Dr. Igor Koralnik, chief of neuro-infectious diseases and global neurology at Northwestern Medicine who also oversees the Neuro COVID-19 Clinic. “About half the patients reported missing more than 10 days of work. … We think long COVID syndrome will have a significant impact on the workforce.”

The most frequently reported neurologic symptoms were “brain fog” (81%), headache (68%), numbness/tingling (60%), disorder of taste (59%), disorder of smell (55%) and muscle pain (55%), according to the study.

In addition, patients also reported experiencing fatigue (85%), depression/anxiety (47%), shortness of breath (46%) and insomnia (33%).

Of the 100 patients in the study, 70% were women and 16% had a pre-existing autoimmune disorder, according to Koralnik. Half of the patients had a confirmed positive COVID-19 test, and while the other half tested negative for COVID-19, all patients had clinical symptoms consistent with the virus, according to Koralnik.

“It is possible that long COVID is not a persistent infection of the nervous system or the lungs, or the GI (gastrointestinal) tract or the heart … by the virus, but a post-infectious autoimmune problem where the virus has actually confused the immune system to think normal components of the body are foreign or (not) normal and need to be attacked,” Koralnik said, adding his lab is researching to see if there is a “blood signature” produced by cells exposed to the virus.

Since women are more likely than men to have autoimmune disorders like rheumatoid arthritis or multiple sclerosis, that could be why more women than men visited the clinic virtually or in person, according to Koralnik.

In addition to autoimmune diseases, participants reported experiencing depression/anxiety (42%), insomnia (16%), lung diseases (16%) and headache (14%) prior to COVID-19 diagnosis.

“We were surprised by the number of patients who were suffering from depression/anxiety before their COVID-19 diagnosis, and this suggests a possible neuropsychiatric vulnerability to developing long COVID,” said Koralnik.

People who tested positive for COVID-19 sought help from the clinic on average a month earlier than those who tested negative, according to Koralnik, who said barriers to care could’ve prevented them from getting treatment sooner.

“This may have been caused by the difficulty for these patients to find medical providers, since they do not fit into classical diagnostic criteria of COVID-19,” he added.

While the symptoms a long hauler can vary from person to person, many said they experienced symptoms on and off for months.

Researchers hoped patients would improve over time, with Koralnik hoping patients would have achieved 90% of their normal pre-COVID-19 functioning nine months after recovering from the virus.

“But that was not the case. Although everybody tends to improve over time, this group as a patient population could not,” he said. “We didn’t see a trend toward recovery over time in this patient population. That indicates time is not a good predictor … for the time it will take someone to recover when they present with long COVID initially.”

Contact Kristen Thometz: @kristenthometz | (773) 509-5452 |  [email protected]

Note: This story was originally published March 24, 2021. It has been updated to include our “Chicago Tonight” conversation.