WASHINGTON — A statement from the American Heart Association in its journal Hypertension notes an association between high blood pressure and increased risk later in life of cognitive impairment.

A review of multiple studies on the relationship between high blood pressure and brain diseases finds the association is especially strong when hypertension occurs in middle age.

“Many observational studies suggest treating hypertension may reduce the cognitive impact of high blood pressure, especially on vascular cognitive impairment, but observational studies are not designed to prove cause and effect,” said Dr. Costantino Iadecola, chair of the writing committee, in a news release.

“We need randomized controlled studies — which do prove cause and effect — to determine if treating high blood pressure, especially in middle age, will also decrease the risk of cognitive impairment later in life,” Iadecola said.

In the meantime, Iadecola recommends people do their best to control high blood pressure because it can pose such a threat to numbers of organs including brains, hearts and kidneys.