June 10, 2014
Scientists have found further evidence that cardiovascular health is tied to brain health, including the risk for Alzheimer’s disease. They found that among mentally alert elderly men and women, those with signs of hardening of the arteries (atherosclerosis) were more likely to have signs of the brain plaques that are a hallmark of Alzheimer’s.
“This is more evidence that cardiovascular health leads to a healthy brain,” said study author Timothy M. Hughes, of the University of Pittsburgh. The findings appeared in the journal Neurology, from the American Academy of Neurology.
For the study, researchers studied a group of 91 seniors, ages 83 to 96, who had no obvious symptoms of Alzheimer’s or other forms of dementia.
The study participants all underwent brain scans to look for evidence of beta-amyloid, the sticky protein that builds up in the brains of those with Alzheimer’s, forming dense plaques. Two types of scans were used, MRI and PET scans, along with a radioactive chemical called Pittsburgh compound B that binds to beta-amyloid and then is detected by PET.
Those in the study also were tested for high blood pressure and evidence of hardening of the arteries (a sign of heart disease), which causes arteries to get clogged and become “stiff” and also results in increased risk of stroke
The researchers found that about half of the seniors had beta-amyloid plaques in their brains. Those with plaques were more likely to have high blood pressure and “stiffer” arteries. The more atherosclerosis, the more likely they were to have plaques and other abnormalities typical of Alzheimer’s in the brain.
“These two conditions may be a ‘double-hit’ that contributes to the development of dementia,” Dr. Hughes said. “Compared to people who had low amounts of amyloid plaques and brain lesions, each unit of increase in arterial stiffness was associated with a two- to four-fold increase in the odds of having both amyloid plaques and a high amount of brain lesions.”
Atherosclerosis was linked to brain plaques independent of whether someone had high blood pressure or was taking blood pressure medications. It also didn’t matter whether someone carried the APOE-E4 gene, another risk factor for Alzheimer’s disease.
“This study adds to growing evidence that hardening of the arteries is associated with cerebrovascular disease that does not show symptoms,” Dr. Hughes said. “Now we can add Alzheimer’s type lesions to the list.”
Other studies have shown that high blood pressure is linked to thinking and memory problems in the elderly, as well as the presence of the plaques and tangles characteristic of Alzheimer’s disease. This study adds to growing evidence about the role of blood vessel health in brain health.
Various factors can help to keep blood vessels supple and reduce the risk of cardiovascular disease. These include a heart-healthy diet–eating plenty of fruits and vegetables, choosing fats like olive oil in place of saturated fats like the fat found in red meat,, and consuming fish rather than red meats. Regular exercise is also known to promote cardiovascular health and, by inference, brain health.
Source: Timothy M. Hughes, PhD, Lewis H. Kuller, MD, Emma J.M. Barinas-Mitchell, et al., “Pulse Wave Velocity Is Associated With Beta-Amyloid Deposition in the Brains of Very Elderly Adults.” Neurology, Vol. 81, pages 1-8, 2013.