Blood pressure control as an intervention to prevent dementia

Observational findings of a relationship between blood pressure during midlife and cognitive brain outcomes have been replicated in different populations, but negative findings have also been reported.1 Often based on cross-sectional studies or on data from very old people (ie, >80 years of age), interpretations of these negative studies have not accounted for issues such as reverse causation.2 As a consequence of inconsistencies in the published literature, blood pressure lowering has not been accepted as a candidate for intervention against cognitive impairment or dementia—a trial was needed.