Patients with mild Alzheimer’s disease who took a specific type of blood pressure drug that penetrates the brain were stabilized in their cognitive decline compared with patients who got different types of blood pressure medicine, according a new study.

For years, high blood pressure has been known as a risk factor for developing dementia. And one previous Japanese study has shown that drugs known as brain-penetrating angiotensin-converting enzyme (ACE) inhibitors were associated with a reduced risk of Alzheimer’s.

However, the new study, which is published in the latest issue of the journal Neurology, is the first in which different groups of patients with mild to moderate Alzheimer’s disease were given different types of blood pressure drugs.

What is especially interesting about this study is that all of the 162 patients had high blood pressure, all were given a blood pressure drug, and all had their blood pressure return to about normal.

But only those patients who got the brain-penetrating ACE inhibitors remained nearly stable after one year, based on their scores on a cognitive test known as the Mini-Mental State Examination, or MMSE.

The other patients, who got one of two other blood pressure drugs, either a non-brain-penetrating ACE inhibitor or a calcium channel blocker, saw a significant decline in their MMSE scores.