December 20, 2007
People with Alzheimer's disease who have high blood pressure, chest pains or an irregular heartbeat may lose their memories faster than others with Alzheimer's disease. The findings appeared in Neurology, the medical journal of the American Academy of Neurology.
Researchers at Johns Hopkins University studied 135 elderly men and women who had recently been diagnosed with Alzheimer's disease. All the seniors had been given memory and cognitive tests over the previous three years.
At the beginning of the study, 62 percent of the study participants had various heart and cardiovascular problems. These included palpitations and irregular heartbeats, high blood pressure and chest pains. Some had undergone heart bypass surgery or had had a heart attack or stroke. Some also had diabetes. The researchers found that those people who had high blood pressure at the time of their Alzheimer's diagnosis saw their rate of cognitive decline accelerate twice as fast as those Alzheimer's patients who did not have high blood pressure. Irregular heartbeats and chest pains due to a lack of blood supply in the heart were also associated with a more rapid decline on cognitive tests.
"The good news is that vascular factors can be modified, so these results may suggest strategies for slowing the progression of Alzheimer's," said study author Michelle Mielke, Ph.D. "Many studies suggest that vascular factors are associated with an increased risk of developing Alzheimer's disease. These findings suggest that vascular factors also affect rate of cognitive and functional decline after a diagnosis, and further research is clearly warranted."
Surgery and Medications
The study also found that people with Alzheimer's who have a history of heart bypass surgery, diabetes or taking medications to treat high blood pressure had a slower rate of cognitive decline. "Our findings further suggest that medications used to treat high blood pressure may be important in slowing the progression of Alzheimer's once a person is diagnosed," said Dr. Mielke. "However, the findings that show heart bypass surgery and diabetes are associated with a slower rate of cognitive decline are counterintuitive," added Dr. Mielke. The researchers call for additional research to explore the link between Alzheimer's and cardiovascular disease.
Various studies have shown that factors that are good for the heart are also good for the brain. A heart-healthy diet rich in fruits and vegetables and low in saturated fats, for example, has been shown to reduce the risk for developing Alzheimer's disease. Exercise, which is good for the heart and blood vessels, may also help to preserve memory and brain function.
For this reason, doctors recommend a heart-healthy diet and lifestyle to preserve the brain. The same recommendations may also apply for those who already show signs of Alzheimer's disease, the current study suggests.
M.M. Mielke, Ph.D., P.B. Rosenberg, M.D., J. Tschanz, Ph.D., e al: "Vascular Factors Predict Rate of Progression in Alzheimer's Disease." Neurology, Volume 69, November 6, 2007, pages 1850-1858.