Cognitive impairment somewhat common after COVID-19 infection

Cognitive impairment occurred relatively often within several months of patients having had COVID-19, according to results of a cross-sectional study published in JAMA Network Open.

“We were hoping to determine the prevalence of cognitive dysfunction in post-COVID patients and whether cognitive dysfunction occurred across the spectrum of disease severity,” Jacqueline H. Becker, PhD, a clinical neuropsychologist and associate scientist in the division of general internal medicine at Icahn School of Medicine at Mount Sinai, told Healio Neurology. “Most prior studies tended to focus exclusively on hospitalized COVID-19 patients when reporting on cognitive dysfunction or did so using a very small number of patients. We wanted to take a look at a larger sample of patients with confirmed mild, moderate or severe COVID-19 and see if it was consistent with early reports.”

Becker and colleagues examined data of 740 patients (mean age, 49 years; 63% women; mean time from COVID-19 diagnosis, 7.6 months) who survived COVID-19 and were treated in outpatient, ED or inpatient hospital settings. Participants were 18 years or older, spoke English or Spanish, tested positive for SARS-CoV-2 or had serum antibody positivity and had no dementia history. The researchers assessed cognitive functioning via well-validated neuropsychological measures. They used logistic regression to examine the link between cognitive impairment and COVID-19 care site, adjusted for race and ethnicity, smoking, body mass index, comorbidities and depression.

Results showed the most significant deficits occurred in processing speed (18%), executive functioning (16%), phonemic fluency (15%) and category fluency (20%), memory encoding (24%) and memory recall (23%). Adjusted analyses revealed hospitalized patients had higher rates of impairments in attention (OR = 2.8; 95% CI, 1.3-5.9), executive functioning (OR = 1.8; 95% CI, 1-3.4), category fluency (OR = 3; 95% CI, 1.7-5.2), memory encoding (OR = 2.3; 95% CI, 1.3-4.1) and memory recall (OR = 2.2; 95% CI, 1.3-3.8) compared with those in the outpatient group. Those treated in the ED had higher rates of impaired category fluency (OR = 1.8; 95% CI, 1.1-3.1) and memory encoding (OR = 1.7; 95% CI, 1-3) compared with those treated in the outpatient setting. The researchers reported no significant differences in impairments in other domains.

“Our findings suggest that a substantial proportion of patients may experience cognitive problems several months after COVID-19, which can contribute to significant functional disability,” Becker said. “It raises concern that SARS-CoV-2 may confer an increased risk for neurodegenerative diseases. There is still much to be learned, but early identification of post-COVID patients with cognitive impairment will be crucial for management and appropriate resource allocation due to the possible reversibility and potential opportunities for interventions, such as cognitive rehabilitation.

“To that end, cognitive screening of post-COVID-19 patients as standard of care may be prudent, regardless of age and COVID-19 severity,” Becker added.