In a new study, nearly a quarter of people with COVID-19 have reported symptoms of brain fog, including memory problems, months after their diagnosis.
The study, published last week in JAMA network open, includes survey responses from 740 people who had had COVID-19 on their demographic characteristics and the cognitive symptoms they were still experiencing. On average, participants were between seven and eight months after their initial diagnosis of COVID-19.
Of these participants, almost a quarter reported having problems with memory (23% of participants, 170 people) and memory encoding (24%, 178 participants). Participants also frequently reported problems with executive functioning, processing speed, and fluency.
Many of these problems can be symptoms of what is colloquially known as brain fog, the study authors write. People who suffer from brain fog may find it difficult to think or process information clearly. They may have difficulty concentrating or find that it takes longer than usual to complete certain mental tasks. Brain fog can be the result of mental health issues (such as anxiety, depression, or chronic stress) or certain underlying medical conditions (including multiple sclerosis).
This study is relatively small, but its conclusions are consistent with those of previous studies. A study published about a year ago found that the majority of people hospitalized with COVID-19 had some kind of neurological problem, including headaches and dizziness, but also cognitive problems. And other research published in April found that even people whose illnesses aren’t severe enough to require hospitalization can still experience brain fog-like symptoms after COVID-19. In fact, this study found that a third of people who contracted the coronavirus developed neurological conditions within six months of their diagnosis.
It is not yet clear why COVID-19 survivors are so likely to exhibit neurological symptoms, including those that could constitute brain fog. Researchers are still investigating whether the coronavirus directly causes long-lasting cognitive problems or whether brain fog could be linked to the trauma associated with surviving a new viral disease amid a global pandemic. As this research and other investigations into the mysteries of the long COVID continue, we will hopefully know more soon. In the meantime, another recent study has shown that getting the COVID-19 vaccine can significantly help prevent the long COVID in the event of a breakthrough infection.