Epidemiological Studies of the Effect of Stroke on Incident Dementia

Abstract

Background and Purpose-Stroke is implicated in the incidence of dementia, and the risk of poststroke dementia is well characterized, but the excess risk of dementia in those with stroke compared with those without stroke is not well known. Methods-We conducted a systematic review of the excess risk of incident dementia conferred by stroke. Studies of the risk of incident dementia in the population with stroke compared with the population without stroke were identified and compared. Results-Sixteen studies were identified with all but one conducted in a community setting. A history of stroke doubles the risk of incident dementia in the older population. This increase is not explained by demographic or cardiovascular risk factors or by prestroke cognitive decline. The excess risk of incident dementia diminishes with time after stroke and may be higher in those without an APOE ⑀4 allele. There is no excess risk of incident dementia in those aged Ͼ85 years with a history of stroke compared to those aged Ͼ85 years without stroke. Conclusions-The effect of stroke on dementia incidence in the population is not explained by common risk factors. At this time of population aging and increased stroke survival, more research is needed to determine to what extent efforts to reduce the incidence of stroke will affect the incidence of dementia. (Stroke. 2010;41:e41-e46.)

Prevalence of Individuals Experiencing the Effects of Stroke in Canada

“…Other researchers have also shown that many individuals diagnosed with dementia have a cerebrovascular cause or contribution to their impairments. 23 It would be difficult to obtain an accurate estimate of the overall prevalence of stroke survivors in Canada unless a comprehensive national survey was to ask questions similar to those that were covered by the Survey of Disability, Aging and Carers. Projecting future trends is notoriously difficult as the future prevalence depends on changes in the incidence of stroke, improvements in treatment, increases in population, and changes in the age structure of the population.…”

Longitudinal Effect of Stroke on Cognition: A Systematic Review

“…Randomized controlled trials and cognitive rehabilitation studies were excluded. Studies in which the only outcome was a diagnosis of dementia were excluded because this was the subject of a previous review 14. Studies were excluded if change in cognitive function over time in the stroke group was not reported (ie, studies that only compared cognitive outcomes in stroke patients versus controls were excluded).…”

Interleukin 1 Receptor and Alzheimer’s Disease-Related Neuroinflammation

“…There is a large amount of data about potential risk factors for AD, including age [1], genetics [2], and injury [3]. Many treatable medical conditions are also associated with an increased risk of AD, including stroke [4], diabetes [5], midlife hypertension [6], and hypercholesterolemia [7,8].…”