In a nutshell
This study reviewed the association between blood pressure levels and reduction in brain volume.
Some background
Hypertension (high blood pressure) is believed to be associated with brain atrophy (a degenerative reduction in the size and function of brain cells). Brain atrophy can be assessed by measuring brain volume. Recent studies have demonstrated an association between hypertension and brain volume, especially in the hippocampal region. The hippocampus is an area of the brain that plays an important role in processing information and storing memories. The hippocampus is one of the first regions of the brain damaged in Alzheimer’s for example. The exact effect of blood pressure on brain volume in different regions is currently under investigation.
Methods & findings
This meta-analysis (an analysis combining data from several similar studies) reviewed 28 different studies. A significant association between hypertension and brain atrophy was shown in 26 of the 28 (92.9 %) studies reviewed. The most commonly affected regions were found to be the frontal lobe, the parietal lobe and the temporal lobe, including the hippocampal region.
In an analysis of four studies including a total of 942 participants, significantly lower hippocampal volume was seen among hypertensive patients compared to patients without hypertension.
In an analysis of three studies including 768 patients, the effect of blood pressure on gray matter volume was examined. The gray matter is the major active component of brain, consisting of the bodies of the nerve cells which generate the electrical signals of the nervous system. No significant association was found between hypertension and gray matter volume in this analysis.
The bottom line
This study concluded that high blood pressure levels are associated with brain volume reduction, especially in the hippocampus and the frontal lobe.
The fine print
This analysis included several trials, all employing different methods of measuring brain volume and blood pressure. This might have created a significant bias in the presented results.
What’s next?
Consult with your physician on how to monitor for, and reduce the risk of, brain atrophy in association with hypertension.
Published By :
Journal of hypertension
Date :
Jun 27, 2013
