Alzheimer's Disease Archive

The U.S. Preventive Services Task Force says there is not enough evidence to support routine screening for dementia or mild cognitive impairment among people ages 65 and older if they have no symptoms.

Widespread screening isn't recommended, but symptoms are cause to get evaluated.

We routinely undergo mammograms and colonoscopies with the objective of catching breast and colorectal cancer early, when they're most treatable. So why don't we also get periodically screened for dementia using questionnaires, blood tests, or imaging scans? The U.S. Preventive Services Task Force—a panel of disease prevention experts—advises that there is no proven value in screening women without cognitive problems.

Adding vitamin E to standard Alzheimer's drugs modestly slows the decline in daily functioning caused by dementia, according to a study in The Journal of the American Medical Association.

The study involved over 600 adults, almost all of them men. Their average age was 79, and all had been diagnosed with mild or moderate Alzheimer's disease. They were already taking one of the standard Alzheimer's medications, such as donepezil (Aricept).

A special form of PET scanning offers a more certain diagnosis for some, but at a steep out-of-pocket cost.

A new kind of brain scan can detect beta amyloid, an abnormal protein associated with Alzheimer's disease. It can be helpful when, based on symptoms and a careful assessment, your doctor suspects Alzheimer's dementia but remains unsure of the final diagnosis. "If your doctor suspects that the underlying cause of your cognitive deficits is Alzheimer's disease, then a scan like this can help corroborate that," says Dr. Gad Marshall, an assistant professor of neurology at Harvard Medical School. "It can help with the hard-to-call cases."

Q. Is it true that B vitamins can reduce my risk of Alzheimer's disease and other types of dementia?

A. The simple answer appears to be "probably not." But few things in medicine are simple. A century ago, we ate a lot more foods rich in B vitamins than we eat today. Diets low in B vitamins—particularly folic acid, vitamin B6, and vitamin B12—can raise blood levels of a natural chemical called homocysteine. This, in turn, can promote atherosclerosis of the arteries of the heart and brain—resulting in heart attacks, strokes, and dementia.

Keeping your blood sugar level in check may help ward off dementia.

Here's another reason to keep your blood sugar under control: increased levels of any kind are now linked to an increased risk of developing dementia. "For the first time, we have a convincing link between dementia and elevated blood sugars, even in the nondiabetic range," says Dr. David Nathan, a Harvard Medical School professor and the director of the Diabetes Center and Clinical Research Center at Massachusetts General Hospital.

Q. Can exercising ward off Alzheimer's disease or dementia?

A. There is pretty strong evidence that regular exercise in people without dementia reduces (but does not eliminate) the risk of cognitive decline and dementia as we age. Several randomized clinical trials of regular exercise report a protective effect on cognitive function. When benefits from a particular behavior are reported, doctors tend to be more inclined to believe the result if they know of a biological mechanism that could explain it. Brain imaging has found somewhat larger volumes of brain tissue, particularly in the parts of the brain essential to memory, among people who exercise regularly.

High cholesterol, high blood pressure, diabetes, and stiffening of the arteries are well-known contributors to cardiovascular disease. These same factors may also promote the development of beta-amyloid plaques in the brain characteristic of Alzheimer's disease. In a study published in Neurology, researchers conducted brain scans on 91 elderly men and women. Although none of the participants showed signs of dementia, about half had significant amounts of amyloid deposits in their brains.

Study participants also underwent tests for cardiovascular health. One measured arterial stiffness, an indicator of the health of the body's vascular system. People with the stiffest arteries showed more amyloid plaque in the brain as well as a greater number of lesions in brain's "white matter," a marker of trouble in the small arteries.

Q. Alzheimer's runs in my family. Will it help to get gene testing for this disease?

A. A relatively small fraction of cases of Alzheimer's disease begin between the ages of 30 and 60—a type called early-onset Alzheimer's disease. In most people with this form of the disease, the cause is one of several mutant genes that the person has inherited from a parent. The primary genes that we know about are called PSEN1, PSEN2, and APP. If someone inherits one of these mutated genes, it is very likely (but not certain) they will develop the disease.

Here's a novel way to help doctors diagnose early dementia among middle-aged people: ask them to put names to famous faces. A study in the Aug. 13, 2013, Neurology found that people with early-onset dementia between the ages of 40 and 65 had far more trouble identifying well-known faces than people in that age group without dementia. Both groups were shown photos of Princess Diana, Albert Einstein, and 18 other iconic celebrities and historical figures. Those with early dementia scored an average of 46% in naming the faces, compared with 93% for those free of dementia. Researchers also tracked how well people in each group scored at recognizing—but not naming—the faces, which may help determine the specific type of cognitive impairment a person has. Researchers say the test may one day help doctors screen people for early dementia and help us understand how the brain works when it comes to remembering and retrieving knowledge of words and objects.