Long-term brain fog and cognitive impairment in previously hospitalized COVID-19 patients.

OBJECTIVES: Limited research exists on COVID-19 associated brain fog, and on the long-term cognitive and psychiatric sequelae in racially and ethnically diverse patients. We characterize the neuropsychological sequelae of post-acute COVID-19 in a diverse cohort and investigate whether COVID-19 clinical severity remains associated with brain fog and cognitive deficits approximately 2 years post infection. METHODS: A cross-sectional study of patients with a history of COVID-19 hospitalization (March-September 2020). COVID-19 clinical severity was indexed using the National Early Warning Score 2 and a comprehensive neuropsychological tele-battery was administered 2 years post discharge. Pearson's r correlations assessed association, while independent sample t-tests examined group differences. Significant outcomes were further analyzed using multiple regression and ANCOVAs, adjusting for key covariates. RESULTS: In 41 adult patients (19 female, 30 Hispanic, 13 Black, mean age of 65 (SD = 15), COVID-19 level of severity was associated with greater number of endorsed brain fog symptoms (Pearson's r = .34, 95% CI [.04, .59]), worse overall cognitive functioning (global cognition: r = -.36, 95% CI [-.61, -.05]) and reduced performance on an attention and working memory task (digit span backwards: r = -.41, 95% CI [-.66, -.09]) at 2-year follow-up. Brain fog symptoms most associated with COVID-19 severity included difficulty focusing (r = .46, 95% CI [.18, .67]), detached (r = .41, 95% CI [.12, .64]) and feeling sleepy (r = .40, 95% CI [.11, .63]). Patients' cognitive performance was generally below average (global cognition z-score: M = -.96, SD = .66), with group differences based on sex and ethnicity evidenced on individual cognitive tests. DISCUSSION: This study emphasizes the importance of continued research on the long-term effects of COVID-19 infection on neuropsychological outcomes, particularly among underrepresented, health-disparate groups. Greater understanding of these associations could improve detection and treatment of those at increased risk of cognitive decline or impairment.

Measuring the Frailty Phenotype and its Association with Cognition in Mid-Life and Older Age.

BACKGROUND: Frailty is directly linked to physical robustness and cognitive decline in older age. The Fried Frailty phenotype (FP) is a construct composed of five core symptoms that has been studied predominately in older age. There is little research contrasting the psychometric properties of the FP in mid-life versus older age. OBJECTIVE: We compared the psychometric properties of the FP in mid-life and older age and investigated relationships between the FP and cognition. METHODS: Frailty and neuropsychological assessments were completed on 361 adults, between 45 and 92 years of age, without primary neurological disorders. Confirmatory factor analysis was used to examine FP, indicated by Grip Strength, Gait Speed, Physical Activity, Fatigue, and Weight Loss. Measurement invariance was tested in mid-life (45-64 years) versus older age (≥65 years). Associations were examined between FP and language, executive functions, memory, processing speed, and visuospatial domains as well as a Generalized Cognition factor. Age was tested as a moderator of these associations. RESULTS: Weight Loss was a poor indicator of FP. Factor loadings were comparable across age groups; however, Fatigue was disproportionately higher among those in mid-life. FP was negatively associated with all cognitive domains and remained invariant across age groups. CONCLUSION: Results support the construct validity of the FP and document its stable associations with poorer cognition in middle and older life. Future research investigating central features of frailty earlier in life may offer avenues for developing targeted prevention measures and better characterization of individuals with elevated dementia risk.

Randomized Trial of Combined Aerobic, Resistance, and Cognitive Training to Improve Recovery From Stroke: Feasibility and Safety.

Background Physical exercise and cognitive training have been recommended to improve cognitive outcomes poststroke, but a multifaceted strategy including aerobic, resistance, and cognitive training to facilitate poststroke recovery has not been investigated. We aimed to assess the feasibility, adherence, and safety of a combined aerobic, resistance, and cognitive training intervention (CARET+CTI) after stroke. Methods and Results We prospectively randomized patients presenting with recent stroke to a comparison of a supervised 12-week CARET+CTI program and a control group receiving sham CARET+CTI. Participants were scheduled for 3 weekly CARET and CTI sessions. All participants underwent pre- and postintervention assessments of strength, endurance, and cognition. The primary outcomes were feasibility and adherence, defined as the ratio of scheduled and observed visits, and safety. We enrolled 131 participants, of whom 37 withdrew from the study. There were 17 (20%) withdrawals in the CARET+CTI and 20 (44%) in the control group. The observed-over-expected visit ratio was significantly higher in the intervention than in the control group (0.74±0.30 versus 0.54±0.38; P=0.003). A total of 99 adverse events were reported by 59 participants, none of which were serious and related to the intervention. Greater gains in physical, cognitive, and mood outcomes were found in the CARET+CTI group than in the control group, but were not statistically significant after adjustments. Conclusions A CARET+CTI intervention, after stroke, is safe, feasible, and has satisfactory participant adherence over 12 weeks. REGISTRATION URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT02272426.