May 19 (UPI) -- Treating high blood pressure may also reduce risk for dementia or cognitive impairment later in life, an analysis published Tuesday by JAMA has found.
Researchers report that treating high blood pressure, or hypertension, with medications such as beta blockers, ACE inhibitors and ARB blockers lowers a person's likelihood of developing dementia by more than 7 percent, and some forms of cognitive decline by more than 20 percent.
Scientists in Ireland, Scotland and Canada reviewed data from 12 clinical trials with more than 92,000 participants who had a mean age of 69.
"Treating high blood pressure with blood pressure medications reduces your risk of developing dementia and cognitive impairment," co-author Dr. Michelle Canavan, consultant geriatrician at Galway University Hospital in Ireland, told UPI.
"The findings of this study add dementia and cognitive impairment to the list of benefits -- like heart disease and stroke -- of lowering blood pressure with medications," she added. "This is a very relevant message for people who want to know how they can age successfully and live independently for as long as they can."
More than half of all American adults -- 108 million -- have high blood pressure, according to the U.S. Centers for Disease Control and Prevention. The agency estimates only about one in four people with high blood pressure have their condition under control.
Meanwhile, about 6 million people in the United States are living with some form of dementia, while another 5 million have some form of cognitive impairment. Dementia is not a single disease, but rather a general term for symptoms of cognitive impairment, including memory loss and communication and thinking difficulties.
Examples of conditions that entail dementia include Alzheimer's disease.
Cognitive impairment is diagnosed when a person has trouble remembering, learning new things, concentrating or making decisions, according to the CDC. Cognitive decline is considered a mild form of cognitive impairment that is expected as a natural part of aging.
All 12 studies analyzed by the researchers reported the incidence of dementia in their patient populations, while eight recorded cognitive decline and eight documented changes in cognitive test scores, the researchers said.
Among all study participants, mean systolic baseline blood pressure was 154 mm Hg and the mean diastolic blood pressure was 83.3 mm Hg.
The researchers found that blood pressure lowering with prescription medications significantly reduced the risk for dementia, by 7 percent, or cognitive impairment, by 7.5 percent, over at least a four-year period.
In addition, eight of the included studies observed that effective blood pressure control reduced risk for cognitive decline by just over 20 percent.
"High blood pressure increases the risk of dementia and cognitive impairment through stroke -- clotting or bleeding -- as well as silent stroke and brain shrinkage," Canavan said. "The effect of lowering blood pressure on the brain not only reduces the risk of stroke but also reduces damage to blood vessels in the brain."