The association between blood pressure and cognitive function

Longer lifespans have been accompanied by an increasing number of older people suffering from impaired cognitive function (dementia) including Alzheimer's disease (AD) and vascular dementia (VaD). Some studies have suggested that hypertension in old age correlates with the pathogenesis of dementia. Since hypertension is potentially reversible, a number of randomized trials have examined whether antihypertensive treatment may help to prevent dementia. We review five studies, all using subjects aged 60 years or older, which investigated different antihypertensive pharmacological treatments and found conflicting results regarding impact on dementia. At the same time, other studies have suggested that hypotension in older people, especially those with low diastolic blood pressure, are also at higher risk for developing dementia. Four studies are reviewed here, but none is able to determine unequivocally if hypotension is a cause or a consequence of dementia in old age.