Antihypertensive treatment is associated with lower risk for dementia in older adults with high blood pressure, a meta-analysis in the Lancet Neurology finds.

Researchers combined data from six prospective studies comprising over 30,000 adults aged 55 and older who were dementia-free at baseline. During a median follow-up of 7 to 22 years, roughly 3,700 developed dementia, nearly half of whom developed Alzheimer disease.

Among participants with hypertension, those who used any antihypertensive agent had a 12% lower risk for dementia and a 16% lower risk for Alzheimer's relative to those not using antihypertensives. No antihypertensive class emerged as superior to others.

Antihypertensive treatment was not associated with reduced dementia risk among participants with normal or pre-hypertensive blood pressure. This group probably included patients with well-controlled hypertension.

Commentators say that with these data, taken together with other analyses, "there is now persuasive evidence for a beneficial effect of blood pressure lowering on cognitive function from treatment initiated in midlife."