Scientific research around the effects of COVID-19 does not stop and is providing more detail on what happens to patients who face symptoms like brain fog after infection.
In the U.S, rates of cognitive dysfunction or brain fog last an average of 7.6 months after patients have had COVID-19 illness.
Mental fog consists of having difficulty in concentration, memory and lack of clarity in thoughts. It can be caused by taking some medications or by the effect of jet lag after many hours of air travel. But the COVID-19 disease can also cause brain fog with specific symptoms.
In a small study with 32 adults, 22 with cognitive symptoms and 10 control participants without themresearchers from UC San Francisco and Weill Cornell Medicine, New York, analyzed cerebrospinal fluid from 17 of the participants who consented to the lumbar puncture.
All participants had had COVID-19 but had not required hospitalization. They found that 10 of 13 participants with cognitive symptoms had abnormalities in their cerebrospinal fluid. But all four cerebrospinal samples from participants without post-COVID cognitive symptoms were normal. The investigation was published on Annals of Clinical and Translational Neurology .
The average age of the participants with cognitive symptoms was 48 years, compared to 39 in the control group. Participants with these symptoms had executive functioning problems, said lead author Joanna Hellmuth, MD, MHS, of the UCSF Center for Memory and Aging. “They manifest as trouble remembering recent events, finding names or words, staying focused, and trouble retaining and manipulating information, as well as slower processing speed“, said.
“Brain fog” is a common side effect of COVID, affecting around 67% of 156 patients at a post-COVID clinic in New York, a study published this month shows. In the current study, patients were enrolled in the Long-Term Impact of Infection with Novel Coronavirus (LIINC) study evaluating recovery in adults with confirmed SARS-CoV-2.
Cerebrospinal fluid examinations revealed elevated protein levels, suggesting inflammation and the presence of unexpected antibodies found in an activated immune system. Some were found in the blood and cerebrospinal fluid, implying a systemic inflammatory response, or were exclusive to cerebrospinal fluid, suggesting brain swelling. While the targets of these antibodies are unknown, it is possible that these could be “rogue” antibodies that attack the body itself.
Immune system goes haywire months after COVID
“It is possible that the immune system, stimulated by the virus, may be working in an undesirable pathological way. This would be the case even if people didn’t have the virus in their bodies,” said Hellmuth, who is principal investigator of the UCSF Coronavirus Neurocognitive Study and is also affiliated with the UCSF Weill Institute for Neuroscience. He also noted that lumbar punctures were performed an average of 10 months after the participants’ first COVID symptom.
The researchers also found that participants with cognitive symptoms had an average of 2.5 cognitive risk factors, compared with an average of less than one risk factor for participants without symptoms. These risk factors included diabetes and hypertension, which can increase the risk of stroke, mild cognitive impairment, and vascular dementia; and a history of ADHD, which can make the brain more vulnerable to executive functioning problems. Other risk factors included anxiety, depression, a history of heavy drinking or repeated use of stimulants, and learning disabilities.
Being the brain fog one of the most frequent sequels, Julián Bustin, head of the Ineco Memory and Gerontopsychiatry Clinicstated that “it is about a complex and disabling condition that prevents patients from maintaining their daily activitiessince it affects both physically and mentally” and maintains that in order to reduce the functional impact of cognitive sequelae and emotional aspects, it is important to be able to approach the patient in a timely manner, applying the appropriate treatment.
“We see more and more neuropsychiatric consequences of COVID in the office. These symptoms can appear up to 12 weeks after having the infection. They are prolonged symptoms that occur in up to 33% of people who had COVID, such as depression, anxiety, post-traumatic stress disorders, sleep problems and mental fog, which is the feeling of fatigue or mental exhaustion, which makes it difficult to concentrate and perform activities of daily living. This gets worse when we do activities, but does not necessarily improve when we rest”, he held to Infobae the specialist.
“It is an issue similar to chronic fatigue syndrome. You feel tired all the time and have difficulty concentrating. We even see it in many patients who did not undergo intensive therapy”said Bustin, who affirms that the first thing a person suffering from these symptoms should have is a good diagnosis: “An evaluation of all neuropsychiatric aspects should be made. The more interdisciplinary the consultation, the better the diagnosis will be. Although there are still no specific treatments for this new ailment, the treatments that are currently used are occupational therapy, pharmacological therapy, psychotherapy, cognitive stimulation and behavioral activation therapy”.
Tests May Fail to Diagnose Mild Cognitive Disorders
All participants in the published study underwent a battery of face-to-face cognitive tests with a neuropsychologist, applying equivalent criteria used for the HIV-associated neurocognitive disorder (HAND). Surprisingly, the researchers found that 13 of 22 participants (59 percent) with cognitive symptoms met the HAND criteria, compared to seven of 10 control participants (70 percent).
“Comparing cognitive performance to normative references may not identify real changes, particularly in those with a high pre-COVID baseline, who may have experienced a noticeable drop but are still within normal limits. If people tell us they have new thinking and memory problems, I think we should believe them instead of requiring them to meet certain severity criteria.Hellmuth specified.
As an important fact, science has identified cognitive symptoms in other viruses, in addition to the COVID-19 and HIV. These include the SARS and MERS coronaviruses, hepatitis C, and the Epstein-Barr virus.