Cognitive decline

About: Cognitive decline is a research topic. Over the lifetime, 29308 publications have been published within this topic receiving 1174689 citations.

The smallest stroke: Occlusion of one penetrating vessel leads to infarction and a cognitive deficit

Abstract: Microinfarctions are present in the aged and injured human brain. Their clinical relevance is controversial, with postulated sequelae ranging from cognitive sparing to vascular dementia. To address the consequences of microinfarcts, we used controlled optical methods to create occlusions of individual penetrating arterioles or venules in rat cortex. Single microinfarcts, targeted to encompass all or part of a cortical column, impaired performance in a macrovibrissa-based behavioral task. Furthermore, the targeting of multiple vessels resulted in tissue damage that coalesced across cortex, even though the intervening penetrating vessels were acutely patent. Post-occlusion administration of memantine, a glutamate receptor antagonist that reduces cognitive decline in Alzheimer's disease, ameliorated tissue damage and perceptual deficits. Collectively, these data imply that microinfarcts likely contribute to cognitive decline. Strategies that have received limited success in the treatment of ischemic injury, which include therapeutics against excitotoxicity, may be successful against the progressive nature of vascular dementia.

Literacy and memory decline among ethnically diverse elders.

Abstract: Literacy may be a more powerful indicator of brain reserve than years of education. Literacy level may be a proxy for native intellectual capacity or life experience that can compensate for brain damage or provide brain reserve. Alternately, the experience of acquiring literacy skills may in itself change the organization of the brain and increase protection against cognitive decline. However, because people with low levels of literacy obtain poor scores on most cognitive measures, only longitudinal studies can elucidate the role of reading ability in reserve. We determined whether literacy skills could predict cognitive change in a sample of 136 English-speaking African American, Caucasian, and Hispanic elders selected from a longitudinal aging study in New York City. According to a physician's independent examination, all participants were nondemented throughout the four longitudinal assessments. Literacy level was assessed using the WRAT-3 reading subtest. After accounting for age at baseline and years of education, GEE analyses showed that elders with low levels of literacy had a steeper decline in both immediate and delayed recall of a word list over time as compared to high literacy elders. Our findings suggest that literacy skills are protective against memory decline among nondemented elders.

Role of inflammation in cognitive impairment: results of observational epidemiological studies and clinical trials.

Abstract: Inflammation may be an important mechanism underlying dementia and cognitive decline in the elderly. Inflammation has been implicated in the neuropathological cascade leading to the development of Alzheimer's disease and other common forms of dementia in later life. These observations have led to observational epidemiological study to define the association of systemic and brain inflammatory markers on cognitive impairment and dementia. Furthermore, clinical trials have been carried out to better elucidate the possible role of nonsteroidal anti-inflammatory drugs (NSAIDs) in the prevention or slowing of progression of Alzheimer's disease. In this review, we discuss the observational epidemiological and clinical trial evidence of the role of inflammation on the occurrence and prevention of dementia or cognitive decline. NSAIDs hold promise to prevent dementia if given in an appropriate time window during the induction phase of dementia and to subjects with apolipoprotein E (APOE) e4 alleles. Also, immunotherapy may prove beneficial.

Cerebral Perfusion and the Risk of Dementia: A Population-Based Study

Abstract: Background: Cerebral hypoperfusion has previously been associated with mild cognitive impairment and dementia in various cross-sectional studies, but whether hypoperfusion precedes neurodegeneration is unknown. We prospectively determined the association of cerebral perfusion with subsequent cognitive decline and development of dementia. Methods: Between 2005 and 2012, we measured cerebral blood flow by 2-dimensional phase-contrast magnetic resonance imaging in participants of the population-based Rotterdam Study without dementia. We determined the association of cerebral perfusion (mL/100mL/min) with risk of dementia (until 2015) using a Cox model, adjusting for age, sex, demographics, cardiovascular risk factors, and apolipoprotein E genotype. We repeated analyses for Alzheimer disease and accounting for stroke. We used linear regression to determine change in cognitive performance during 2 consecutive examination rounds in relation to perfusion. Finally, we investigated whether associations were modified by baseline severity of white matter hyperintensities. Results: Of 4759 participants (median age 61.3 years, 55.2% women) with a median follow-up of 6.9 years, 123 participants developed dementia (97 Alzheimer disease). Lower cerebral perfusion was associated with higher risk of dementia (adjusted hazard ratio, 1.31; 95% confidence interval per standard deviation decrease, 1.07–1.61), similar for Alzheimer disease only, and unaltered by accounting for stroke. Risk of dementia with hypoperfusion was higher with increasing severity of white matter hyperintensities (with severe white matter hyperintensities; hazard ratio, 1.54; 95% confidence interval, 1.11–2.14). At cognitive reexamination after on average 5.7 years, lower baseline perfusion was associated with accelerated decline in cognition (global cognition: β=−0.029, P =0.003), which was similar after excluding those with incident dementia, and again most profound in individuals with higher volume of white matter hyperintensities ( P value for interaction=0.019). Conclusions: Cerebral hypoperfusion is associated with accelerated cognitive decline and an increased risk of dementia in the general population.