A type of drug used to control high blood pressure may protect brain functions, according to new research.

A team from Wake Forest University studied centrally acting ACE inhibitors and found that they may reduce inflammation that could be part of Alzheimer's disease, a news release said.

The drugs are a special class that can cross the blood-brain barrier.

"High blood pressure is an important risk factor for Alzheimer's disease and vascular dementia," said lead author Dr. Kaycee Sink. "Our study found that all blood pressure medications may not be equal when it comes to reducing the risk of dementia in patients with hypertension."

Someone is diagnosed with dementia every 70 seconds, the release said. Hypertension, or high blood pressure, is a major contributor to the development of all types of dementia. Many of the estimated one in three U.S. adults who have hypertension are treated with ACE inhibitors, a class of drugs that help lower blood pressure by causing the blood vessels to relax and widen.

The study was based on watching almost 6,000 people over 65 years old in several locations around the country. About 1,000 were dementia-free when the study started. People who were exposed to ACE inhibitors that cross the blood-brain barrier saw an average 65 percent less cognitive decline per year of exposure compared to participants taking other blood pressure medications.

Researchers also found that non-centrally active ACE inhibitors were associated with an increased risk of dementia and the people taking them were more likely to develop difficulty performing daily activities.

The study appeared in the current issue of Archives of Internal Medicine.