These days, we're so busy answering questions from readers that I never get to ask my own. Maybe next month!
Dear Dr. Prescott,
Has the Oklahoma Medical Research Foundation looked into whether lowering people's blood pressure could be contributing to the rising rates of Alzheimer's disease?
My thinking is that the body naturally increases its blood pressure in response to a specific need, such as poorer circulation brought on by age. So could blood pressure-lowing medications have the effect of reducing the amount of blood — and oxygen — reaching the brain?
— Dick, Stillwater
Dr. Prescott prescribes
Blood pressure is the force applied against the walls of the arteries as the heart pumps blood through the body. High blood pressure, or hypertension, results when the blood flow exerts excessive force against arterial walls.
Typically, this increased force is caused not by a specific need — such as the need for more oxygen in the brain — but because muscles in the walls of the arteries contract and cause the arteries to narrow. When this happens, the heart continues to pump with the same strength as if your arteries are unconstricted. But, in fact, it is now pushing the blood through a smaller space.
Just think about a hose hooked to a spigot. If you stick your thumb over half of the opening, what happens to the water? For the same amount of water to come out, there has to be a greater force in the hose. That's what's happening with high blood pressure.
While your body can tolerate elevated blood pressure for months, even years, the excessive force eventually can cause damage to your heart, kidneys and eyes. And brain.
Studies have found that people suffering from untreated high blood pressure are more likely to develop memory and cognition problems. But when patients who displayed vascular problems were treated, they showed a 40 percent lower risk of subsequently developing Alzheimer's than those who were not.
In studies involving cholesterol-lowering statin drugs such as Lipitor, Zocor, Crestor and Vytorin, researchers also have seen a link between decreased blood pressure and reduced rates of Alzheimer's. In an examination of the brains of elderly participants in a study about dementia, scientists found that in those who had taken statin drugs, their brains displayed fewer small brain lesions and fewer of the tangles and? plaques associated with Alzheimer's.
Although scientists still have not established the cause of most cases of Alzheimer's disease, these findings certainly point to the conclusion that what's good for your heart is good for your mind. And there is no doubt that keeping your blood pressure at manageable levels is key to your long-term cardiovascular health.
There have been anecdotal reports of statin drugs causing side effects such as memory loss and fuzzy thinking. But when Pfizer conducted an extensive clinical trial of its best-selling cholesterol drug Lipitor, it found no link between the drug and memory loss.
If your doctor has prescribed a cholesterol-lowering medication of any kind, I would recommend that you continue to take it. As always, be sure to monitor any side effects and to talk to your physician. So long as you're not experiencing problems, controlling your blood pressure will help your heart — and, most likely, your brain too.
Prescott, a physician and medical researcher, is president of the Oklahoma Medical Research Foundation. Cohen is a marathoner and OMRF's senior vice president and general counsel.