COVID-19 survival was associated with increased risk for longitudinal cognitive decline, according to study findings published in JAMA Neurology.
SARS-CoV-2 is linked to a variety of neurological sequelae with cognitive impairment observed during the acute and subacute phases of COVID-19. To date, it remains unclear what the long-term cognitive outcomes from COVID-19 infection may be.
To better understand cognitive outcomes, patients (n=1438) aged 60 years or older who were discharged from one of three hospitals in Wuhan, China between February and April 2020 were contacted by telephone at 6 and 12 months after discharge. Patients were evaluated using the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) and the Telephone Interview of Cognitive Status-40 (TICS-40). Uninfected spouses (n=438) were recruited as the control individuals.
Survivors and control individuals were aged median 69 (interquartile range [IQR], 66-74) and 67 (IQR, 66-74) years, 51.95% and 49.32% were women, 39.01% and 34.47% had hypertension, 19.05% and 18.49% had diabetes, and 13.42% and 13.93% coronary heart disease, respectively.
Among the COVID-19 survivors, 1178 had nonsevere and 260 severe cases. The severe case cohort was older, had more comorbidities, more had been admitted to the intensive care unit, and receive oxygen support.
TICS-40 scores were lower among the survivors at 6 (median, 29 vs 30 points; P <.001) and 12 (median, 29 vs 31 points; P <.001) months compared with control individuals. Among survivors, those with severe COVID-19 had lower TICS-40 scores at 12 months (median, 24 vs 30; P <.001).
At 6 months, IQCODE scores were highest among the severe disease cohort (median, 3.63 points) followed by nonsevere cohort (median, 3.18 points; P <.001) and control individuals (median, 3.06 points; P <.001). The proportion of individuals with cognitive decline in the first six months was highest among the severe cohort (60.77%) followed by nonsevere (28.86%; P <.001) and control (21.00%; P <.001) groups.
Between 6 and 12 months, cognitive decline was more rapid among the severe cases (slope, -0.039) than nonsevere cases (slope, -0.0003; P <.001) or control individuals (slope, 0.002; P <.001).
Overall, 12.45% of survivors had cognitive impairment at 12 months. Among the severe disease group, 10.00% had dementia and 26.54% mild cognitive impairment (MCI) at 6 months and at 12 months, 15.00% had dementia and 26.15% had MCI. These rates were higher than the control individuals and those who had nonsevere COVID-19 (all P <.001).
Severe COVID-19 was associated with increased risk for cognitive impairment at 12 months (adjusted odds ratio [aOR], 9.10; 95% CI, 5.61-14.75; P <.001), early-onset cognitive decline (aOR, 4.87; 95% CI, 3.30-7.20; P <.001), late-onset cognitive decline (aOR, 7.58; 95% CI, 3.58-16.03; P <.001), and progressive cognitive decline (aOR, 19.00; 95% CI, 914-39.51; P <.001).
Nonsevere COVID-19 was associated with increased risk for early-onset cognitive decline (aOR, 1.71; 95% CI, 1.30-2.27; P <.001).
This study may have been limited by relying on telephone cognitive assessments.
“It is worth noting that 21% of individuals with severe cases in this cohort experienced progressive cognitive decline, suggesting that COVID-19 may cause long-lasting damage to cognition,” the researchers stated. “These findings imply that the pandemic may substantially contribute to the world dementia burden in the future.”
Liu Y-H, Chen Y, Wang Q-H, et al. One-Year Trajectory of Cognitive Changes in Older Survivors of COVID-19 in Wuhan, China: A Longitudinal Cohort Study. JAMA Neurol. 2022;e220461. doi:10.1001/jamaneurol.2022.0461