University of Denver Researchers Study the Impact of Long COVID

Sarah Ritchey undergoes several tests in DU's Human Dynamics Lab.

More than two years after the World Health Organization declared the COVID-19 outbreak a pandemic, the U.S. is closer to shifting to an endemic, meaning the disease persists but does not cause significant disruption to daily life.

Globally, the number of new COVID cases, hospitalizations and deaths continues to decline. However, millions of people who have recovered from the acute phase of the disease are struggling to find complete healing as they deal with what is being referred to as “long COVID.”

Sarah Ritchey battled through the acute phase of COVID on three separate occasions. From her initial diagnosis in March 2020 to her most recent in December 2021, she has struggled with lasting symptoms. Severe fatigue, “brain fog” when trying to remember things, exacerbated allergies, shortness of breath, numbness and tingling in her hands and feet are some of the ailments she deals with on a daily basis.

“The loss of smell and taste doesn’t matter in the same way as I physically can’t go to work,” Ritchey says. “My only option is to work from home.”

All of this is why on an early April morning Ritchey made the drive from her home in Colorado Springs to the University of Denver’s Human Dynamics Lab in the Daniel Felix Ritchie School of Engineering and Computer Science. There, faculty and student researchers are working to understand the symptoms afflicting patients with long COVID and to develop possible treatments. They are building off more than six years of research surrounding the effects of concussions.

“We think about COVID in the acute phase, but long COVID looks really different,” says Bradley Davidson, director of the Human Dynamics Lab and an associate professor in the Ritchie School. “If you list out the symptoms for postconcussive syndrome and you list out the expanding list of symptoms for long COVID, there is a pretty significant overlap.”

Davidson is working with Kim Gorgens, professor in the Graduate School of Professional Psychology, and Daniel Linseman, professor in the College of Natural Sciences and Mathematics, on both the concussion and long COVID research. They currently are recruiting participants who, like Ritchey, have had COVID longer than three months ago who are willing to undergo testing to see how their vestibular ocular and neurocognitive systems are functioning.

“If we expect some answers from doctors, there has to be testing and research,”Ritchey says. “I’m curious to see what my scores turn out and where I fall with this testing.”

Data from the Human Dynamics Lab is shared with High Definition Physical Therapy (HDPT), a community partner that has helped accelerate the recovery time for those suffering from concussion, to help determine if there are treatments that can help those struggling with long COVID.

“We had patients coming in for concussive treatment that were getting better, but after they had COVID, their symptoms were regressing back to how they presented at the start of their concussion,” says Dan Stoot, a vestibular physical therapist specializing in concussions and traumatic brain injuries with HDPT. “We have to think more physically [about] what are the physiological explanations for all this and how can a virus impact movement systems.”

DU and HDPT are starting the research with 100 patients — 50 with long COVID symptoms and 50 without — and aim to have initial results this summer, when they will decide whether to expand the study.

The initiative has attracted the attention of MITRE, a federally funded research and development center that works on projects for various department of the government. MITRE, with locations all over the world including Colorado Springs, is developing innovation hubs where they connect with local universities to help deliver high-impact research. This is MITRE’s first partnership with DU.

“Even if COVID becomes endemic, people are still going to suffer from long COVID into the foreseeable future,” says Matt Stein, a chief engineer with MITRE. “There are millions of people who can benefit from an actual shortened treatment plan that allows them to get back to normal, back to being healthy sooner.”

Stein says that this research is of interest to government agencies beyond the Department of Health and Human Services. The Department of Defense and Department of Veterans Affairs are also eager to learn the outcomes of the study. He says that long COVID is affecting what is called “force readiness,” meaning the military personnel who are ready to respond to orders when they are given. If the length of time those suffering from long COVID can be shortened, personnel can be returned to force-ready status sooner.

Gorgens says the parallels between their research on long COVID and postconcussive syndrome could also be invaluable to military personnel.

“COVID infection looks like a brain injury; it has the same metabolic and inflammatory signatures,” she says. “Tracking those changes over time, especially among service personnel and other folks who are in populations where brain injury is overrepresented, will be really important.”

Linseman is taking long COVID research a step further through partnerships with National Jewish Health and Resilience Code. More than a year ago, he recognized the similarities between traumatic brain injuries and COVID.

Currently, this research team is recruiting patients who fall into three categories: those with a history of concussion but not COVID; those who have had COVID but no history of concussion; and those with a history of both. They intend to study the neurological effects by looking at biomarkers in blood to see what is happening in the brain of these patients.

“We want to know what is it about this virus that is causing these long-term neurological effects and try to figure out what things we can do to blunt that,” Linseman says. “We have formulated a hypothesis that folks who have had a history of concussion or traumatic brain injury probably are predisposed to having more severe or chronic neurological effects post-COVID.”

Only research will tell if something can be done to minimize the time and side effects of those struggling from long COVID.

“One reason I am passionate about our concussion research and now the COVID research is because benign neglect is how our medical establishment has traditionally dealt with both conditions,” Davidson says. “What treatment did patients get when they had COVID? Stay at home, rest, and stay away from everyone. I didn't think that is satisfactory. Unfortunately, with long COVID, we are seeing that too: Let’s neglect it because there is really nothing we can do. Our work is built on the fact that this treatment model just isn't good enough for concussions or long COVID.”

If you are interested in participating in the studies, please email DenverLongCOVIDStudy@gmail.com for more information.