I've been able to view the 2021 Alzheimer's Association International Conference (AAIC) virtually this week, and plan to share several reports I saw on the forum. Here is a summary from MedPage today of a talk from yesterday.
Note that the researchers refer to toxic-metabolic encephalopathy (TME) in patients, which resonates with anyone who knows Dr. Bredesen's views on toxic and inflammatory contributors to cognitive impairment and risk of Alzheimers and other dementia.
This talk is from an ongoing international consortium of
scientific leaders, including the Alzheimer’s Association and representatives from more than 25 countries — with technical guidance from the WHO —[who] formed an international, multidisciplinary consortium to collect and evaluate the short- and long-term consequences of the viral infection on the central nervous system (CNS), as well as the differences across countries on the viral impact of COVID-19. This study aims to better understand the long-term consequences that may impact the brain, cognition and function — including underlying biology that may contribute to Alzheimer’s and other dementia....This study will enroll two groups of individuals:
People with confirmed cases of COVID-19 from hospitals that have been discharged. They will be evaluated for follow up evaluations at 6, 9 and 18 months. People who are enrolled in existing international research studies to add additional measures and markers of their underlying biology.
https://www.alz.org/research/for_resear ... rain-study
The talk had data from Amerindian Argentinians living in the Andes, and people in Greece and NYC., so duly noted that it doesn't cover everyone, in all locations and at all ages and circumstances.
Wisniewski and colleagues evaluated plasma biomarkers total tau (t-tau), neurofilament light (NfL), glial fibrillary acid protein (GFAP), ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), and species of amyloid beta (Aβ40, Aβ42) and phosphorylated tau (ptau-181) -- indicators of injury in the brain, neuroinflammation, and Alzheimer's disease -- in COVID-19 patients.
The researchers assessed plasma samples from 310 patients admitted to New York University Langone Health. All were positive for SARS-CoV-2: 158 people had neurological symptoms and 152 did not. People with new neurologic symptoms were older (median age 71 versus 63).
The most common neurological symptom was confusion due to toxic-metabolic encephalopathy (TME), which accounted for 51% of new neurologic diagnoses....
Tau, NfL, UCH-L1, and GFAP also significantly correlated with inflammation markers, including C-reactive peptide. This may suggest inflammation-related blood-brain barrier disruption accompanying neuronal or glial injury, Wisniewski noted.
"These findings indicate that patients who had COVID-19 may have an acceleration of Alzheimer's-related symptoms and pathology, but that clearly needs longer follow-up," he said.
Post-COVID Cognitive Decline and Health
In the study from Vavougios's [Greek] group, which also was part of the global SARS-CoV-2 consortium, researchers studied cognitive impairment and health measures in 32 previously hospitalized mild to moderate COVID-19 patients 2 months after discharge. Participants had a mean age of 62 and no history of neurodegenerative disease or stroke before SARS-CoV-2 infection.
More than half (56.2%) of participants presented with cognitive decline, as indicated by a MoCA score under 24. Predominant patterns of cognitive impairment were short-term memory impairments or multi-domain impairment without short-term memory deficits.
Worse cognitive test scores correlated with higher age, waist circumference, and waist-to-hip ratio. Worse memory and thinking scores were independently associated with lower oxygen saturation levels during a 6-minute walk test, after adjusting for age and sex.
"A brain deprived of oxygen is not healthy, and persistent deprivation may very well contribute to cognitive difficulties," Vavougios observed. "These data suggest some common biological mechanisms between COVID-19's dyscognitive spectrum and post-COVID-19 fatigue that have been anecdotally reported over the last several months."