Hospitalized COVID-19 survivors showed greater cognitive impairment 6 months later, compared with patients hospitalized for other causes, but the overall disease burden was similar, based on data from 85 adults with COVID-19.
Previous studies have shown that cognitive and neuropsychiatric symptoms can occur from 2-6 months after COVID-19 recovery, and such symptoms are known to be associated with hospitalization for other severe medical conditions, Vardan Nersesjan, MD, of Copenhagen University Hospital, 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, they said.
In a study published in JAMA Psychiatry (2022 Mar 23. doi: 10.1001/jamapsychiatry.2022.0284), the researchers identified 85 adult COVID-19 survivors and 61 controls with non-COVID medical conditions who were treated and released between July 2020 and July 2021. The COVID-19 patients and controls were matched for age, sex, and ICU status. Cognitive impairment was assessed using the Mini-International Neuropsychiatric Interview, the Montreal Cognitive Assessment (MoCA), neurologic examination, and a semistructured interview to determine subjective symptoms.
The primary outcomes were the total scores on the MoCA and any new-onset psychiatric diagnoses. Secondary outcomes included specific psychiatric diagnoses such as depression, neurologic examination findings, and self-reported neuropsychiatric and cognitive symptoms. The mean age of the COVID-19 patients was 56.8 years, and 42% were women.
At 6 months’ follow-up, cognitive status was significantly lower in COVID-19 survivors, compared with controls, based on total geometric mean MoCA scores (26.7 vs. 27.5, P = .01). However, cognitive status improved significantly from 19.2 at hospital discharge to 26.1 at 6 months in 15 of the COVID-19 patients (P = .004), the researchers noted.
New-onset psychiatric diagnoses occurred in 16 COVID-19 patients and 12 of the controls (19% vs. 20%); this difference was not significant.
Secondary outcomes were not significantly different at 6 months between the groups, with the exception of anosmia, which was significantly more common in the COVID-19 patients; however, the significance disappeared in adjusted analysis, the researchers said.
The study findings were limited by several factors including the inability to prove causality because of the case-control feature and by the inability to detect small differences in neuropsychiatric outcomes, the researchers noted.
However, the results were strengthened by the use of a prospectively matched control group with similar disease severity admitted to the same hospital in the same time frame. Although the overall burden of neuropsychiatric and neurologic symptoms and diagnoses appeared similar in COVID-19 patients and those with other medical conditions, more research in larger populations is needed to determine smaller differences in neuropsychiatric profiles, the researchers noted.