COVID Research Roundup

by Denis Storey
March 6, 2024 at 12:50 PM UTC

Multiple studies suggest that the recovery from COVID will take longer than the original pandemic.

Clinical relevance: Multiple studies suggest that the recovery from COVID will take longer than the original pandemic.

  • Brain fog could be connected to dysregulated blood-brain barriers and coagulation.
  • Long COVID is associated with low iron levels and persistent inflammation.
  • COVID-19 survivors show cognitive deficits, especially in memory and reasoning tasks.

It’s been four years since COVID shut down the world and kept us all at home for what seemed like an eternity. And while most of us have moved on, neuroscience remains committed to studying the lingering aftermath of that life-changing year.

A trio of studies emerged over the past several days that remind us – again – that the recovery will take longer than the original pandemic.

Possible Brain Fog Origin Identified

Brain fog – that mental sluggishness or muddiness that hinders concentration and memory – showed up early on in the pandemic. And now researchers might have discovered a potential source of the mysterious malaise that seems to hit more than one out of every five COVID patients.

Researchers in Dublin, Ireland, have found that some brain fog sufferers have dysregulated blood-brain barriers that can leak, and dysregulated coagulation, that can linger for a year or more after the initial infection.

Their findings, which appear in Nature Neuroscience, are based on blood tests and MRI scans of the study participants.

A Long COVID Clue?

Long COVID, despite its prevalence, has remained a puzzling infection risk. But a team of Cambridge University researchers appears to have uncovered a link between long COVID and a lack of iron in the blood.

The data, appearing in Nature Immunology, shows that 45 percent of those who took part in the study reported symptoms of long COVID between three and 10 months later.

The research team – comprised of researchers at the Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), along with their Oxford counterparts, found that persistent inflammation – a normal immune response to infection – and low iron levels in the blood, contributing to anaemia and disrupting healthy red blood cell production, could be seen as early as two weeks post COVID-19 in those individuals reporting long COVID many months later.

“Iron levels, and the way the body regulates iron, were disrupted early on during SARS-CoV-2 infection, and took a very long time to recover, particularly in those people who went on to report long COVID months later,” researcher Aimee Hanson explained. “Although we saw evidence that the body was trying to rectify low iron availability and the resulting anaemia by producing more red blood cells, it was not doing a particularly good job of it in the face of ongoing inflammation.”

COVID Threatens Cognition

Brain fog isn’t the only long-term consequence of COVID infection. Research out of the Imperial College London shows “small deficits in the performance of cognitive and memory tasks in people who had recovered from COVID-19 compared with those who had not had COVID-19.”

The study, which ran in the New England Journal of Medicine, is notable for its breadth – with a sample size of nearly 150,000.

The research showed small deficits that remained apparent even a year – or longer – post-infection. These deficits lingered longer for those whose symptoms persisted for more than four months, those who’d been hospitalized, or anyone infected with one of the earliest variants.

The deficiencies popped up in various ways, but appeared most significant in memory, such as recalling photo subjects they’d looked at a few minutes earlier. The researchers attribute it to the brain’s inability to craft new memories. Other problems cropped up in executive and reasoning abilities, including spatial planning or verbal reasoning.

On the other hand, the study showed that vaccines offered a protective effect that mitigated the extent of the deficits.

Vaccine Overkill?

Finally, speaking of vaccines, once scientists heard about news reports of a 62-year-old German man who asked for – and received – 162 COVID vaccines in less than three years, they couldn’t wait to get him into the lab.

But they had to be at least a little disappointed when they published what they found in The Lancet. They found that while the overeager vaccinator didn’t suffer any adverse reaction to the multitude of vaccines, he didn’t reap any additional benefits, either.

“Importantly, we do not endorse hypervaccination as a strategy to enhance adaptive immunity,” the study’s authors wrote.

Further Reading

Study Reveals Paxlovid Does Little to Stave Off Long COVID

Report: Mental Health Decline Among Healthcare Workers Started During COVID

Rethinking Mental Health in a Post-COVID World

A Randomized, Double-Blind, Placebo-Controlled Pilot Trial of the Acute Antisuicidal and Antidepressant Effects of Intranasal (R,S)-Ketamine in Severe Unipolar and Bipolar Depression With and Without Comorbid Alcohol Use Disorder

Intranasal ketamine induced rapid antidepressant effects versus placebo but did not significantly change suicidal ideation scores in patients with alcohol use disorder and suicidal ideation with past attempt.

Gregory H. Jones and others

Case Report

Inhalant Screening in Early Adolescence: Missed Opportunity to Prevent Escalation to Polysubstance Use and Related Consequences

The authors present a case of polysubstance use in an adolescent for whom undetected inhalant use played a key role in escalation of substance use and psychiatric comorbidities.

Jennifer Yokoyama and others