Taking steps to avoid heart disease and stroke may be the best way to preserve your brainpower as you age, new research suggests.
A study in the April 2, 2013 issue of the journal Neurology compared the scores of nearly 8,000 older adults on two widely used health assessment tools. In conjunction with their research, the scientists administered cognitive tests to study participants three times over a period of 10 years to identify declines in memory, reasoning, vocabulary, and two measures of verbal fluency. The researchers found that the tool that focuses primarily on cardiovascular risk factors such as history of heart disease, irregular heartbeat, blood pressure, and cholesterol levels (the Framingham Risk Score from the long-running Framingham Heart Study) was a better predictor of dementia than a second tool that includes assessment of broader factors such as education, body weight, and exercise levels thought to be associated with dementia risk (the Cardiovascular Risk Factors, Aging and Dementia (CAIDE) prediction tool).
The Framingham Risk Score was strongly associated with declines in four out of five cognitive tests, and also helped identify potentially reversible risk factors for use in prevention, while the CAIDE was much less strongly linked to cognitive decline, and in only three of the five test areas.
WHAT YOU CAN DO
Viswanathan suggests the following strategies to lower your cardiovascular risk and help protect your brain from cognitive decline:
- Schedule regular medical exams to help identify cardiovascular problems early. Consult with your doctor to learn about lifestyle changes that can help you improve your health.
- Check your own blood pressure regularly with a home monitor. A systolic reading (the upper number) of greater than 140, or a diastolic reading of greater than 90 can spell danger for your brain and should be reported to your doctor.
- Manage medical conditions such as diabetes, high blood pressure, obesity, and high cholesterol that can negatively affect the cardiovascular system.
- Enjoy a healthy lifestyle with a well-balanced, low-calorie diet low in saturated fats, sugar and sodium, regular exercise (30 minutes most days of the week) and avoidance of smoking and excess alcohol consumption.
“This paper further highlights the importance of vascular intervention as a way to prevent dementia,” says Anand Viswanathan, MD, PhD, a neurologist with MGH’s Stroke Service and Memory Disorders Unit. “The heart and brain do not exist in isolation—they are closely connected to one another by blood vessels. The brain is dependent on a healthy heart and blood vessels to supply it with an abundance of oxygen- and nutrient-rich blood. Any pathology that damages the cardiovascular system can cause similar damage in the brain.”
“In the past, AD-related dementia, characterized by memory loss and the accumulation of toxic proteins in the brain, among other symptoms, was thought to be distinct from vascular dementia, or VaD,” explains Dr. Viswanathan. “VaD is dementia linked to cardiovascular disease that is characterized by declines in mental processing speed, language ability, attention, executive functions such as decision-making and planning, and sometimes also by declines in learning and memory. However, a consensus is growing among experts that the two conditions overlap, with the majority of people who develop dementia having some degree of both pathologies, termed ‘mixed dementia.’ One indication of this overlap is that risk factors for cardiovascular disease have also been shown to be risk factors for developing AD.”
VaD leads to a reduction in blood flow to the brain. This reduction may be caused by a major stroke involving the blockage or rupture of a blood vessel feeding the brain; a series of small, imperceptible strokes; or disease of the small vessels of the brain which supply the white matter networks involved in signaling between brain areas.
Like AD, VaD involves cognitive impairment that interferes with daily activities—but unlike AD, the brain injury wrought by diseases affecting the heart and blood vessels can be slowed or prevented by tackling cardiovascular risk factors. These risk factors include high blood pressure, history of stroke, high LDL “bad” cholesterol levels, coronary artery disease, occlusion (narrowing) of blood vessels leading to the brain, heart rhythm abnormalities, diabetes, obesity, and smoking. In most individuals, cardiovascular risk factors can be managed with medication and lifestyle changes.
“I advise my patients to be as aggressive as possible in addressing VaD risk factors,” says Dr. Viswanathan. “Try to be aware of symptoms that may indicate cardiovascular problems. Focus on prevention, and treating and improving your vascular health. Getting your risk factors under control as early as possible can help delay cognitive decline by 10 or 15 years or more—a huge gain.
“It’s also very important to keep a good eye on how you’re performing in everyday life. Look for cognitive changes—no amount of imaging and testing can screen for cognitive decline as well as the patient can.”