Even though they had a higher risk of vascular disease, older people who used blood pressure-lowering drugs that crossed the blood-brain barrier had better memory recall for up to three years than those who took medications that didn’t.
According to new study published today in the American Heart Association journal Hypertension, older individuals receiving blood pressure-lowering drugs that penetrate the blood-brain barrier had superior memory recall over time than those taking other types of high blood pressure medications.
In older individuals, high blood pressure, or hypertension, is a risk factor for cognitive decline and dementia. Nearly half of all people in the United States have high blood pressure. In one major experiment, treating high blood pressure with blood pressure-lowering medications reduced the cases of moderate cognitive impairment by 19%. (SPRINT MIND).
Blood pressure-lowering medications include ACE inhibitors, angiotensin II receptor blockers (ARBs), calcium channel blockers, and diuretics. Each class reduces blood pressure in a different way, and some of them pass the blood-brain barrier, affecting cognitive function.
“Research has been mixed on which medicines have the most benefit to cognition,” said study author Daniel A. Nation, Ph.D., an associate professor of psychological science in the Institute for Memory Impairments and Neurological Disorders at the University of California, Irvine. ”Studies of angiotensin II receptor blockers and angiotensin-converting-enzyme (ACE) inhibitors have suggested these medicines may confer the greatest benefit to long-term cognition, while other studies have shown the benefits of calcium channel blockers and diuretics on reducing dementia risk.”
This is the first meta-analysis to evaluate the long-term effects of blood pressure-lowering drugs that pass the blood-brain barrier against those that don’t. The medicines were tested for their effects on attention, language, verbal memory, learning, and recall, among other cognitive domains.
“Hypertension occurs decades prior to the onset of dementia symptoms, affecting blood flow not only in the body but also to the brain,” Nation said . “Treating hypertension is likely to have long-term beneficial effects on brain health and cognitive function later.”
Researchers compiled data from 14 research including almost 12,900 people aged 50 and above. Studies from the United States, Australia, Canada, Germany, Ireland, and Japan were included. The meta-analysis found:
- Even though they had a greater degree of vascular risk, older individuals receiving blood pressure-lowering medications that pass the blood-brain barrier had superior memory recall for up to 3 years of follow-up than those taking medicines that did not cross the blood-brain barrier.
- Adults who used hypertensive drugs that didn’t pass the blood-brain barrier had improved attention for up to three years.
“These findings represent the most powerful evidence to-date linking brain-penetrant ACE-inhibitors and angiotensin receptor blockers to better memory. It suggests that people who are being treated for hypertension may be protected from cognitive decline if they medications that cross the blood-brain barrier,” said study co-author Jean K. Ho, Ph.D., a postdoctoral fellow at the University of California, Irvine.
When blood pressure is 120/80 mm Hg or greater, it is termed high. According to the current American Heart Association/American College of Cardiology guidelines for managing high blood pressure, people with readings of 130/80 mm Hg or above should make dietary and exercise modifications, as well as take blood pressure medication, depending on their risk status. Blood pressure-lowering medication is advised if blood pressure exceeds 140/90 mm Hg.
The authors were unable to account for variations in racial/ethnic background based on the available research, and there is a greater proportion of men in the group who used medicines that pass the blood-brain barrier than there is in the group who did not.
Previous studies have indicated that persons of diverse racial/ethnic origins may respond differently to different blood pressure medicines, thus this is an essential topic for further research.