An often-overlooked fact about Alzheimer's disease is that, given current medical knowledge, it can only be definitively diagnosed at autopsy, by looking at the patient's brain. While the patient is still alive, doctors technically can only make a diagnosis of "probable Alzheimer's," largely by systematically ruling out other possible causes of the patient's symptoms. Recent government statistics suggest that as many as 10 to 20 percent of cases diagnosed as "probable Alzheimer's" turn out, at autopsy, to have been something else-often one of many conditions including viral infection, depression, drug interactions, and vascular dementia that can mimic the symptoms of Alzheimer's.
For these reasons, one of the key areas in Alzheimer's research is the search for better diagnostic techniques. This issue's inside feature, " Unmasking Alzheimer's," reports on promising new approaches. Several of them use medical imaging techniques (such as MRI) to look in the brain of living patients for tell-tale signs: clusters of abnormal proteins, called amyloid plaques, that accumulate in the brains of Alzheimer's patients. Being able to detect these plaques in a living patient, without waiting for autopsy, would be a very significant step forward in our ability to diagnose, understand, and beat this disease.
Alzheimer's isn't the only way in which brains can be damaged over time. Chronic alcohol abuse also harms the brain and, as our cover story reports, binge drinking may be especially harmful. Alcohol intoxication doesn't just interfere with our ability to think, learn, and drive; it can also cause long-term changes in the brain that persist years after a person stops drinking. One of the most worrying effects is on neurogenesis: the newly-discovered ability of adult human brains to grow new brain cells. Chronic alcohol abuse may not just interfere with the function of existing brain cells; it may kill off cells and suppress the brain's ability to provide replacements for them.
Moderate alcohol use-about one glass of beer or wine per day for females and double that for males-is less problematic. In fact, some studies suggest that red wine contains chemical compounds that may actually enhance mental function and even prevent Alzheimer's. So if you enjoy an occasional glass of wine with dinner, you probably have nothing to worry about-as long as you're able to stop there. But for those who drink to intoxication every day, or who binge drink at weekend parties, the new research offers a sobering truth: the cost of heavy alcohol use may be measured in brain function lost.
Catherine E. Myers, Ph.D.
Editor-In-Chief, Memory Loss and the Brain