Roundup: COVID’s Brain Fog Linked Biologically to ‘Chemo’ Effect in Cancer Patients; Benefits of Walking to Ease Pain from Knee Arthritis; and More

Long COVID’s ‘Brain Fog’ Biologically Similar to Cognitive Impairment from Chemotherapy in Cancer Patients

Brain fog, or cognitive impairment, has been cited often in previous studies as a common lingering symptom of COVID-19. A new study led by researchers at the Stanford University School of Medicine has found that this condition is biologically similar to cognitive impairment caused by cancer chemotherapy, a condition that has come to be known as “chemo brain.”

In both cases, excessive inflammation damages the same brain cells, the researchers found. The new finding, published in the peer-reviewed, scientific journal Cell, could help guide treatments for cognitive effects of COVID-19, the study’s authors state. The study relied on data of mice with mild COVID-19 infection and postmortem human brain tissue collected early in the pandemic. Brain fog from COVID usually encompasses short-term memory loss, confusion and difficulty concentrating to varying degrees.

“We found that even mild COVID can cause prominent inflammation in the brain that dysregulates brain cells and would be expected to contribute to cognitive impairment,” stated Michelle Monje, M.D., professor of neurology and neurological sciences at Stanford University, in a news release.

How “chemo brain” develops has been studied for years, creating a well-established resource for helping COVID patients, Dr. Monje adds. “The exciting message is that because the pathophysiology is so similar, the last couple of decades in cancer therapy-related research can guide us to treatments that may help COVID brain fog.”

A team of researchers at Stanford has spent two decades studying cognitive impairment after cancer. “They uncovered key details in how chemotherapy impairs the function of the brain’s white matter, regions of the brain normally rich in well-insulated nerve fibers that quickly transmit signals from one place to another,” states a news release about the new study.

For many cancer patients, the symptoms of “chemo brain” are subtle and short-lived. But others may experience continuing cognitive deficits beyond the active treatment phase. Fortunately, there are cognitive training strategies and other therapies that may reduce the burden of cognitive impairment in cancer patients.

Brain fog linked to COVID-19 can linger for months in COVID patients, even among those whose initial overall symptoms were moderate and did not require hospitalization, according to a study from the Mount Sinai Health System in New York released in October.

Walking as Exercise Helps Reduce Bouts of Pain in Those with Knee Osteoarthritis

Walking regularly as exercise can help reduce knee pain and bouts of stiffness and aches for adults aged 50 years and older with knee osteoarthritis, according to a new study published in Arthritis & Rheumatology.

Researchers from the Baylor College of Medicine in Houston reviewed data on a group of participants aged 50 years or older with knee osteoarthritis who were enrolled in a community-based observational study from 2004 to 2006. Their goal was to assess the association between walking for exercise and its impact on symptomatic and progressive knee osteoarthritis.

They surveyed more than 1,200 participants with knee osteoarthritis, which is the most common type of arthritis in the U.S. and is typically the result of wear and tear, and progressive loss, of articular cartilage.

“The findings from our study provide a glimmer of hope that there may be an inexpensive intervention that modifies the structure and symptoms related to osteoarthritis, the most common type of arthritis and a source of substantial disability,” the study’s authors write. “Beyond a benefit in symptoms for osteoarthritis, the findings from our study also suggest that walking may also provide a structural benefit for a large portion of the community with osteoarthritis.”

Of the 1,212 participants in the study, 73 percent walked for exercise regularly. The researchers found that those who walked had a reduced likelihood of new frequent knee pain and medial joint space narrowing, which is when cartilage no longer keeps the bones a normal distance apart. 

The participants’ baseline knee pain was monitored by using radiographs to assess their osteoarthritis. Researchers also surveyed participants to keep a record of their exercise routines. They’re symptoms were analyzed at regular follow-up visits when they are asked about the frequency of their knee pain.

“These findings support that walking for exercise should be encouraged for people with knee osteoarthritis,” the study concludes. “Furthermore, we offer a proof of concept that walking for exercise could be disease modifying, which warrants further study.”

CDC: Certain Improvements in Ventilation Systems in K-12 Schools Reduce Rates of COVID Infections

Strategies to improvement ventilation in K–12 public schools were associated with reduced incidence of COVID-19 among students and staff in schools, according to a new study from the U.S. Centers for Disease Control and Prevention (CDC).

Among 11 ventilation improvement strategies assessed, the four most frequently reported were relocating activities outdoors when possible (74 percent), having existing HVAC (heating, ventilation and air conditioning) systems inspected and validated since the start of the pandemic (70 percent), and opening doors (67 percent) and windows (67 percent) when safe to do so, said the CDC.

Nonetheless, higher-cost and resource-intensive ventilation strategies, such as using portable high-efficiency particulate air (HEPA) filtration systems in classrooms, were reported less often, said the CDC.

The National School COVID-19 Prevention Study (NSCPS) is an “ongoing population-based, longitudinal study that explores implementation and effectiveness of COVID-19 prevention strategies in a representative sample of U.S. K–12 public schools,” the agency states. The “sampling frame” consists of surveys of school administrators or “school-level designees familiar with COVID-19 prevention strategies” from public schools in the 50 states and the District of Columbia.

“With regard to HVAC and HEPA filtration systems, having inspected and validated existing HVAC systems was reported as the only strategy used by a majority of schools,” the CDC said.

The other strategies related to HVAC and HEPA filtration systems “require additional resources with varying costs,” the agency added.

Differences by locale and “school poverty level” in implementing more resource-intensive strategies might be due to “supply chain challenges, differences in school or community resources, or accessibility of technical assistance and support for applying to available sources of funding,” the CDC stated.