COVID linked to 'significant' cognitive problems even in milder cases

A new study has found that COVID-19 infections, including ones that didn't result in hospitalization, can result in 'significant cognitive deficits' that persist after the symptoms have resolved. The study builds upon the growing body of evidence that COVID-19 can result in long-term symptoms in some people, as well as potential neurological problems ranging from loss of smell to brain fog.

This new study, which was recently published in The Lancet, explored the possible cognitive issues that may arise after COVID-19 symptoms have resolved, as well as the presence of these issues "across the full spread of disease severity," meaning not just among those who were hospitalized.

The research involved data on more than 81,000 people; these participants took a Great British Intelligent Test assessment, as well as filling out a questionnaire about their both suspected and self-reported COVID-19 symptoms. The researchers controlled for potentially influential factors, including things like age, preexisting conditions, income, and more.

Using the data, the study ultimately found that people who had contracted and later recovered from COVID-19 — including people who no longer had any symptoms — experienced 'significant cognitive deficits' compared to control subjects.

While these issues substantially impacted those who had been hospitalized with the disease, the study also found that participants who hadn't been hospitalized were also hit with cognition issues after recovering. The findings back up claims from some people who say they've experienced severe brain fog long after their symptoms of the infection resolved.