HIGH blood pressure is an established risk factor for cognitive decline and dementia in older adults, illustrating the importance of antihypertensive treatment regimens in prevention efforts. A recent meta-analysis is the first of its kind to assess the potential cognitive benefits over time of blood-brain barrier-crossing renin-angiotensin system drugs compared with their nonpenetrant counterparts. These medicines were evaluated for their effects on seven cognitive domains, including attention, language, learning, recall, and verbal memory.
Daniel Nation, study author and Associate Professor of Psychological Science, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, California, USA, outlined the relevance of the study: “Research has been mixed on which medications have the most benefit to cognition. 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.”
A total of 14 studies comprising 12,849 patients were included in this investigation. Older adults taking blood-brain barrier-crossing renin-angiotensin medications had better memory recall for up to 3 years of follow-up, relative to individuals taking nonpenetrant drugs, despite their higher vascular risk burden. In contrast, people taking antihypertensive medicines that did not cross the blood-brain barrier showed better attention over the same follow-up period.
Jean K. Ho, study co-author and Postdoctoral Research Fellow at the University of California, Irvine, noted: “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 [take] medications that cross the blood-brain barrier.”
There were several limitations of this meta-analysis. For example, based on the available studies, the researchers were unable to account for differences in racial and ethnic background. Furthermore, there was a higher proportion of males in the group who took blood-brain barrier-crossing medications.
In summary, the researchers succeeded in demonstrating links between blood-brain barrier-crossing renin-angiotensin drugs (e.g., ACE inhibitors and angiotensin II receptor blockers) and less memory decline.