Episodic long-term memory in post-infectious SARS-CoV-2 patients.

Area of Science:

• Neurology
• Cognitive Science
• Infectious Disease Research

Background:

• Long-term memory (LTM) deficits are frequently reported in patients recovered from COVID-19, impacting their overall prognosis.
• The exact cause of these memory issues—whether primary amnesia or secondary to executive dysfunction/inattention—remains debated.
• This study investigates the prevalence and cognitive etiology of LTM impairments in post-SARS-CoV-2 patients, considering confounding factors.

Purpose of the Study:

• To assess LTM functioning in COVID-19 survivors, controlling for premorbid and disease-related factors.
• To explore the cognitive underpinnings of LTM deficits in the post-COVID-19 population.
• To determine the prevalence of LTM impairments in individuals with and without a prior risk for cognitive decline.

Main Methods:

• Retrospective collection of cognitive data (MMSE, MoCA, BMT) from 54 COVID-19-recovered patients.
• Categorization of patients into those at risk for cognitive decline (RCD+) and not at risk (RCD-).
• Conversion of cognitive measures into equivalent scores (ESs) for standardized comparison.

Main Results:

• Mild-to-moderate prevalence of LTM deficits (ESs=0/1) observed in both RCD+ (31.8%-31.8%) and RCD- (28.6%-39.3%) groups.
• Overall cognitive scores (MMSE, MoCA) correlated with BMT performance, but not the MoCA-Attention subtest.
• Asymptomatic RCD+ patients showed better BMT performance than those requiring oxygen therapy.

Conclusions:

• COVID-19 survivors may exhibit LTM deficits with both primary and secondary causes.
• Screening for LTM deficits is advisable, especially for individuals with moderate COVID-19 or pre-existing cognitive risks.
• Both first- and second-level verbal LTM measures are suitable for assessment, with first-level measures potentially being more sensitive.