Oxford Warns Mild COVID Can Reduce Cognitive Performance For Months

Mild cases of COVID-19 that don't result in obvious "long COVID" symptoms may still trigger memory and attention problems, according to a new study from the University of Oxford. Though participants who'd previously had and recovered from mild COVID were found to have similar test results as the study's control group, there were two areas related to cognitive performance that were noticeably worse.

According to the study, which was recently published in the journal Brain Communications, mild COVID-19 infections may result in months of impaired memory and attention. That's based on a series of cognitive tests given to participants who didn't report any ongoing health concerns after recovering from COVID-19. The researchers focused specifically on the "cognitive functions critical for daily life," the study notes, including everything from motor control to the ability to maintain sustained attention.

While the participants were able to "perform well" in most of the areas tested, the researchers found their ability to maintain sustained attention and episodic memory were both "significantly worse" for up to several months following recovery.

The durations varied, with sustained attention taking a hit for up to nine months in the participants, and episodic memory remaining degraded for up to six months — at least compared to the uninfected control group. The results were apparent despite the recovered participants and uninfected controls both having similar levels of anxiety, sleep patterns, fatigue, and forgetfulness.

The researchers point out these deficits were discovered even though the participants didn't report feeling any lingering symptoms when they took the tests. The good news is that, according to the study, both aspects of cognitive performance eventually returned to normal in "most" of the participants by the time they were tested nine months later.

Though many people recover from COVID-19 without any obvious chronic issues, some individuals suffer from long-term consequences for several months or longer after recovering from the initial infection (via CDC). Dubbed "long COVID," this public health concern is more common in people who developed severe infections, though it can potentially hit anyone who has contracted the virus.

Long COVID complaints include everything from (sometimes debilitating) brain fog to more obscure and surprising issues like "COVID toes" and other skin manifestations. Some long-haulers may experience multiple issues, including chronic fatigue, trouble breathing, neurological issues like tingling sensations, and cognitive issues like mood problems and trouble with concentrating.

Harvard refers to long COVID as an "unseen public health crisis," noting that by this point in the pandemic, there are millions of people around the world experiencing long-duration issues that may interfere with their daily lives, including the ability to hold a job, take care of a family, and even, in some cases, care for themselves.

The exact reasons for the various chronic issues remain largely unknown at this time, leaving many feeling hopeless with inadequate solutions for treating their newly developed health problems. Because this is a new disease and we're only a couple of years into the pandemic, it's not yet clear how many long-haulers will ultimately make a full recovery.

Though the data is still evolving as more information becomes available, long COVID issues appear to hit many people in age groups where they're still likely to be in the middle of their careers (via New England Journal of Medicine). This combined with the severe nature of some long COVID symptoms has raised concerns about the pandemic's potential impact on both public health and the economy for years to come.