In this article
- Introduction
- Preventing a Complex Disease Like AD is a Challenge
- AD Risk Factors We Can’t Control
- The Search for AD Prevention Strategies
- The Search for Other Clues That May Contribute to Prevention Strategies
- What Can You Do?
- A Final Word of Caution
- For More Information
The Search for AD Prevention Strategies continued...
Examining high blood pressure. Scientists also have found associations among AD, high blood pressure that begins in midlife, and other risk factors of stroke, such as age, diabetes, and cardiovascular disease. It is known that even in relatively healthy older adults, high blood pressure and other stroke risk factors can damage blood vessels in the brain and reduce the brain’s oxygen supply. This damage may disrupt nerve cell circuits that are thought to be important to decision-making, memory, and verbal skills. Scientists are studying the connections between AD and high blood pressure in hopes that knowledge gained will provide new insights into both conditions.
Learning about diabetes and insulin resistance. Large-scale population studies suggest that diabetes is associated with several
types of dementia, including AD and vascular dementia (a type of dementia associated with strokes, sometimes referred to as multi-infarct dementia). These studies have found that AD and
type 2 diabetes share several characteristics, including increasing prevalence with age, genetic predisposition, and deposits of two different kinds of damaging amyloid protein (in the brain for AD and in the pancreas for type 2 diabetes). Abnormal glucose (a type of sugar) regulation, a key element of diabetes, also has been associated with development of AD. Scientists are working to learn more about this association.
Researchers also are becoming increasingly interested in the possible role of insulin resistance (a condition in which the body produces insulin but cells do not use it properly) in AD. Too much insulin in the blood (which happens as a result of insulin resistance) may encourage inflammation and oxidative stress, both of which contribute to the damage seen in AD.
Possible relationships between cognitive decline, AD, and diabetes are being explored in the Religious Orders Study, which involves a large group of older priests, nuns, and brothers who have been working with scientists funded by the NIA since 1993. This study has provided a wealth of information about many aspects of AD, including the possible link between diabetes and cognitive decline and AD. In one analysis involving more than 800 study participants, researchers examined tests of five “cognitive systems” involved with word and event memory, information processing speed, and the ability to recognize spatial patterns. They found that diabetes was associated with declines in some cognitive systems but not others. The researchers also found a link between those with diabetes and an increased risk of developing AD.