Preliminary Findings on Cognitive Dysfunction in University-Educated Patients After Mild COVID-19 Disease.

The study lacked a control group, so it is impossible to definitively rule out that the observed deficits were due to other factors or pre-existing conditions, although the authors argue that the high education level makes poor premorbid functioning unlikely. Participants were self-selected from a clinic for people with persistent symptoms, meaning they are not representative of all individuals who had mild COVID-19. Not all participants had their infection confirmed by PCR or antibody tests; some were diagnosed based on clinical symptoms and physician judgment. The study used international norms for most tests, which may not be perfectly calibrated for the Swedish population, potentially affecting the accuracy of the T-scores.

The authors declared no conflicts of interest. The study was approved by the Ethics Committee in Sweden and funded by the authors' institution (implied by the lack of external funding statements).

Do not assume these cognitive deficits are mild or transient because the initial infection was mild. The study found profound, persistent memory and executive function problems in a highly educated cohort, with nearly half showing scores 1 SD below the mean on verbal memory 18 months post-infection. Furthermore, because there was no control group, we cannot know if these deficits are specific to COVID-19 or shared with other causes of long-term fatigue and cognitive dysfunction.