Cerebrovascular changes, including decreased cerebral blood flow, occur early in the development of Alzheimer's disease and may accelerate disease progression. In a study published online this week in the journal Hypertension nilvadipine – a calcium channel blocker for the treatment of high blood pressure – increased cerebral blood flow in the hippocampus – brain memory and learning center – among people with Alzheimer's disease without affecting others parts of the brain. Nilvadipine, a dihydropyridine calcium antagonist used as an antihypertensive agent, increased hippocampal cerebral blood flow (CBF) while lowering blood pressure in people with Alzheimer's disease. These results suggest that the known decrease in CBF in Alzheimer's patients may be reversed in some regions. Image Credit: OpenStax College / Anatomy & Physiology, cnx.org / CC BY 3.0. ”
Dr. Jurgen Claassen from Radboud University Medical Center and colleagues tried to find out if nilvadipine could help treat Alzheimer's disease by comparing the use of nilvadipine and placebo among people with mild to moderate Alzheimer's.
The researchers randomly assigned 44 participants to receive either nilvadipine or a placebo for six months.
At the start of the study and after six months, they measure blood flow to specific areas of the brain using a unique magnetic resonance imaging technique.
The results showed that blood flow to the hippocampus increased by 20% among the nilvadipine group compared to the placebo group.
The blood flow to other areas of the brain was unchanged in both groups.
Systolic blood pressure was reduced on average by 11.5 mm Hg.
"This high blood pressure treatment keeps lifting as it does not seem to reduce blood flow to the brain, which can cause more harm than good," Dr. Claassen said id.
"Although no medical treatment is without risk, treatment of high blood pressure may be important to maintain brain health in patients with Alzheimer's disease."
Participants were screened between 2013 and 2015 as part of a major research project comparing nilvadipine with placebo among more than 500 people with mild to moderate Alzheimer's disease.
In the larger project, effects on cerebral blood flow were not measured.
In general, no clinical benefit was found with the use of nilvadipine. However, a subset of patients with only mild disease symptoms provided a slower decline in memory.
"In the future, we need to find out whether the improvement of blood flow, especially in the hippocampus, can be used as a supportive treatment to slow the progression of Alzheimer's disease, especially in previous disease states," said Dr. Claassen. " " et al. . Effects of nilvadipine on cerebral blood flow in patients with Alzheimer's disease. A random test. Hypertension released online June 17, 2019; doi: 10.1161 / HYPERTENSIONAHA.119.12892