Memory loss related to COVID infection

In a new study published in The New England of Medicine,Hampshire et al. bring clarity to how SARS-CoV-2 infection may affect cognition.

They studied 800,000 adults from a larger community sample of more than 3 million persons in the Real-Time Assessment of Community Transmission (REACT) study of SARS-CoV-2 transmission in England. Using an online assessment tool for cognitive function with eight domains, the investigators estimated global cognitive scores among participants who had been previously infected with SARS-CoV-2 and had had symptoms that persisted at least 12 weeks, whether resolved or not, and among uninfected participants.

Modest cognitive decline occurred with the original virus and with each viral variant, including B.1.1.529 (omicron). As compared with uninfected participants (control), cognitive deficit — commensurate with a 3-point loss in IQ — was evident even in participants who had had mild Covid-19 with resolved symptoms. Participants with unresolved persistent symptoms had the equivalent of a 6-point loss in IQ, and those who had been admitted to the intensive care unit had the equivalent of a 9-point loss in IQ.

The greatest deficits in cognitive function were associated with the original strain of the virus (before December 1, 2020) and the early B.1.1.7 (alpha) variant (from December 1, 2020, to April 30, 2021).

Reinfection contributed an additional loss in IQ of nearly 2 points, as compared with no reinfection.

Source: NEJM