Newswise — Chicago, IL – A new study published in Annals of Clinical and Translational Neurology looked at the evolution of neurologic symptoms in non-hospitalized COVID-19 long-haulers at the Northwestern Medicine Neuro COVID-19 Clinic and discovered most long-haulers continue to experience symptoms such as brain fog, numbness/tingling, headache, dizziness, blurred vision, tinnitus and fatigue on average of 15 months after disease onset. Researchers analyzed patients 6-9 months after their initial visit to the Neuro COVID-19 Clinic and discovered heart rate, blood pressure variation and gastrointestinal symptoms increased in long-haulers, while loss of taste and smell decreased overall. The findings are a follow-up to the Northwestern Medicine research team’s March 2021 study that discovered 85% of long-haulers experience four or more neurologic symptoms which impact their quality of life, and in some patients, their cognitive abilities.

“This new study is novel and reports the longest follow-up period of neurologic symptoms impacting non-hospitalized patients suffering from long-COVID anywhere in the world,” said Igor Koralnik, MD, chief of Neuro-infectious Diseases and Global Neurology at Northwestern Medicine, who oversees the Neuro COVID-19 Clinic. “We were surprised by the persistence of most of the debilitating neurologic symptoms of our patients, and by the late appearance of symptoms that suggest dysfunction of the autonomic nervous system.”

Researchers focused this study on patients evaluated initially between May and November 2020 who had mild initial COVID-19 symptoms (ex: transient cough, sore throat) and never required to be hospitalized for pneumonia or low oxygen levels. Of the 52 patients who completed the follow-up study:

  • Average age was 43
  • 73% were female
  • 77% received the COVID-19 vaccine
  • Most continued to experience neurologic symptoms, fatigue, and compromised quality of life 11-18 months after disease onset, an average of 15 months

Overall, there was no significant change in the frequency of most neurologic symptoms between first and follow-up appointments including brain fog (81 vs 71%), numbness/tingling (69 vs 65%), headache (67 vs 54%), dizziness (50 vs 54%), blurred vision (34 vs 44%), tinnitus (33 vs 42%) and fatigue (87 vs 81%).

While loss of taste (63 vs 27%) and smell (58 vs 21%) decreased overall, heart rate and blood pressure variation (35 vs 56%) and gastrointestinal symptoms (27 vs 48%) increased at follow-up.

Patients reported improvements in their recovery, cognitive function, and fatigue, but quality of life measures remained lower than the average population of the United States. Seventy-seven percent of the patients had been vaccinated for COVID-19, but the vaccine didn’t have a positive or detrimental impact on cognitive function or fatigue.

“Vaccination didn’t cure long COVID symptoms, but didn’t worsen them either, which is a reason given by some long-haulers for not getting vaccinated,” said Dr. Koralnik. “As new variants emerge and the number of patients impacted by long COVID rises, we’re now focusing our research on understanding the root cause of long COVID. We’re also devising interventions to improve the management of those patients and find the best treatment options for them.”

To date, the Northwestern Medicine Neuro COVID-19 Clinic has treated nearly 1,400 long-haulers from across the U.S. For more information, visit and to schedule an appointment, please call 312.695.7950.

Journal Link: Annals of Clinical and Translational Neurology