An estimated 5.2 million Americans have Alzheimer’s disease, and it could steal the minds of one out of eight baby boomers, according to a report released on Tuesday by the Alzheimer’s Association.

The report found there were 411,000 new cases of Alzheimer’s in 2000, a number expected to grow to 454,000 new cases a year by 2010. By 2050, 959,000 people will be diagnosed with the disease every year, the report predicts.

The report, available on the Internet here, says that 14 percent of all people age 71 and over have dementia.

That includes 16 percent of women and 11 percent of men in that age group.

Alzheimer’s disease is the most common type of dementia, accounting for 60 to 80 percent of cases.

It starts out with mild memory loss and confusion but escalates into complete memory loss and an inability to care for oneself. There is no cure and the handful of drugs that can treat Alzheimer’s only slow its progression for a short time.

The second most common cause of dementia is vascular dementia, often caused by strokes.

The causes of Alzheimer’s disease are not yet clear. The brains of patients are clogged with protein plaques and tangles of nerve fibers. Corporate and academic scientists are working on tests for disease risk, better drugs to treat the symptoms and vaccines that might prevent the brain damage.

Another study released this week supports the potential broad reach of the epidemic.

COMMON MEMORY LOSS

It found that more than a third of Americans over the age of 70 have some form of memory loss.

The team at Duke University Medical Center, the University of Michigan, the University of Iowa, the University of Southern California and the Rand Corporation found that about 12 percent of patients with cognitive impairment progress to full dementia every year.

Writing in the Annals of Internal Medicine, the researchers said they studied 856 people. They took a neuropsychological examination and family members were asked to evaluate their memory, ability to complete daily activities and medical history.

They were then followed from July 2001 through March 2005.

“These findings illustrate that nearly every family will be faced with the challenges of caring for a family member with some form of memory impairment,” said Brenda Plassman of Duke, who led the study.

“Given how common cognitive impairment without dementia is, physicians should be alert to this problem as they evaluate and treat the patient for other medical problems,” said Dr. Robert Wallace of the University of Iowa.

“This may have significant ramifications because it means that patients may not be able to accurately portray their symptoms and may not retain important information about their treatment.”

“As the population ages and works longer, understanding the extent of cognitive impairment in the older population is critically important,” said Richard Suzman of the National Institute on Aging, one of the National Institutes of Health.

“Research is now beginning to suggest that interventions such as controlling hypertension and diabetes or perhaps cognitive training might help maintain or improve mental abilities with age.”

By Maggie Fox

WASHINGTON (Reuters)