Key Takeaways

  • COVID-19 patients were classified as ‘long haulers’ when symptoms persisted more than six weeks after infection.
  • Long haulers are commonly diagnosed with ‘brain fog’ - a term encompassing neuropsychiatric symptoms such as depression, anxiety and insomnia as well as attention and executive function difficulties
  • Clinicians seeing patients with these symptoms should thoroughly investigate the root causes of the brain fog to be able to identify and treat the underlying conditions

In the patients we treated with long COVID who presented with “brain fog” we found that the root cause of this commonly used term is often multifactorial.

Zeina Chemali, MD, MPH
Investigator, McCance Center for Brain Health, Massachusetts General Hospital

BOSTON – More than two years after the COVID-19 pandemic erupted, scientists have become increasingly aware of a group of patients — so-called ‘long haulers’ — who remain plagued by a combination of symptoms long after the infection passes. In a study published in the Journal of Clinical Neuroscience, specialists from Massachusetts General Hospital (MGH) describe  their findings related to their multidisciplinary clinical work in this area.

“Commonly, patients with long COVID present with ‘brain fog’, a vague description including lack of sleep, anxiety, depression and a history of headache or migraine combined with trouble with attention and word finding difficulties as well as executive dysfunction,” says Zeina Chemali, MD, MPH, director, Neuropsychiatry Clinics and Training at MGH, and medical director of the McCance Center for Brain Health . “In the patients we treated with long COVID who presented with “brain fog” we found that the root cause of this commonly used term is often multifactorial.”

In their study conducted over 15 months from February 2020-May 2021, Chemali and colleagues followed 87 confirmed and 13 presumed cases of non-hospitalized individuals with lasting symptoms beyond six months after COVID-19 infection.

A key feature of the study is that most (75%) of the cohort were white educated women. “Even though we know Black Americans and Latinx individuals got very sick with COVID-19, we did not see them in the long haulers clinic,” notes Chemali who emphasizes this finding likely follows from disparity in healthcare with inability to find time and access to the care needed.

The post-COVID-19 long haulers clinic quickly became the launching base to advance the NIH-funded RECOVER study with principal investigator Ingrid Bassett, MD, investigator in the hospital’s Division of Infectious Diseases. The study is aims to understand how and why COVID-19 affects people differently. “The most important question is what is it in a person’s make-up that influences how they react to COVID-19 in a specific way and exhibit certain symptoms?” Chemali asks. “Why do some people get very sick, others do not, some become long haulers and why do some people never get COVID-19 at all?”  To date, approximately 200 patients have been referred from the MGH COVID-19 long haulers clinic to the RECOVER Study and other trials conducted at throughout the Mass General Brigham healthcare system.  

“Everyone is still grappling with understanding long COVID,” concludes Chemali, noting that similar symptoms are found in patients with other post-viral diseases, post-traumatic brain injury, concussive syndrome or the vaguely understood chronic fatigue syndrome. “From a neurocircuitry point of view, we see that frontal networks are the most vulnerable in the post-COVID-19 phase.”

Chemali suggests that addressing ways to restore frontal neurocircuitry — such as good quality sleep, alleviating pain and headaches, treating anxiety and depression, and targeting attention and executive functions — as well as offering support and promoting self-care are the pillars of a good and sustainable recovery.

About the Massachusetts General Hospital 
Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The Mass General Research Institute conducts the largest hospital-based research program in the nation, with annual research operations of more than $1 billion and comprises more than 9,500 researchers working across more than 30 institutes, centers and departments. In August 2020, Mass General was named #6 in the U.S. News & World Report list of "America’s Best Hospitals."