Cognitive outcomes worse in COVID-19 survivors than in others with similar illnesses

Cognitive impairment was more severe in hospitalized COVID-19 patients compared with those with other illnesses who required hospitalization, according to a study published in JAMA Psychiatry.

“Several disease mechanisms play a role in the development of neuropsychiatric illness during and after COVID-19,” Vardan Nersesjan, MD, of Copenhagen University Hospital in Denmark, and colleagues wrote. “However, it remains unknown if COVID-19 is associated with a unique pattern of cognitive and mental impairment compared with other similarly severe medical conditions.”

Researchers sought to investigate the level of cognitive disruption, neuropsychiatric diagnoses, as well as neurological symptoms, in those who survived COVID-19 compared with others who were hospitalized for non-COVID-19 illnesses of the same severity.

The study took place in a tertiary referral hospital in Copenhagen, Denmark, between July 2020 and July 2021, and included 85 COVID-19 survivors (mean age 56.8 years, 42 women) and 61 matched controls (mean age 59.4 years, 27 women) who were evaluated 6 months after the onset of symptoms that required hospitalization.

Participants’ cognitive and neuropsychiatric states were assessed with the Mini-International Neuropsychiatric Interview, the Montreal Cognitive Assessment (MoCA), and a semi-structured interview for subjective symptoms.

Primary outcomes were total MoCA score and new onset of ICD-10 psychiatric diagnoses. Secondary outcomes included specific psychiatric diagnoses, subjective symptoms and neurologic examination results. All outcomes were adjusted for age, sex, ICU admission, admission length and days of follow-up.

Results showed that cognitive status as measured by MoCA scores at follow-up was lower for COVID-19 survivors (26.7; 95% CI, 26.2-27.1) than cognitive status in controls (27.5; 95% CI, 27.0-27.9). A total of 16 of 85 patients with COVID-19 and 12 of 61 controls revealed a new-onset psychiatric diagnosis during follow-up, but not one that was significantly different (OR, 0.93; 95% CI, 0.39-2.27).

Data additionally revealed marked cognitive improvement, from 19.2 (95% CI, 15.2-23.2) to 26.1 (95% CI, 23.1-29.1) for 15 patients with COVID-19 who underwent MoCA evaluations at discharge.

“Further studies with larger samples are needed to investigate if smaller differences in neuropsychiatric profiles exist,” Nersesjan and colleagues wrote.