Alzheimer's disease for the first time has emerged as one of the leading causes of death in Los Angeles County, mirroring a fast-growing and increasingly costly nationwide trend tied to the aging baby boomer generation, health officials said Wednesday.

The death rate from Alzheimer's jumped 220% — or from 5 to 16 deaths out of every 100,000 people — from 1994 to 2003, according to a new county Department of Public Health mortality report. Alzheimer's is now the eighth-leading cause of death — the first time it has broken the top 10.

The increase is attributed in part to changes in reporting and better diagnosis of the disease. But health experts say it is clear that an expanding senior population — one in which people are living longer than ever before — is closely linked to the growing number of people afflicted with the brain disorder.

"As our population ages, the chance of having Alzheimer's goes up," said Dr. Jonathan Fielding, the county's director of public health. At age 65, a person has a one in 10 chance of contracting the disease; by 85, those chances increase to one in two, experts say.

The financial toll to the nation's healthcare system could be staggering as the number of people over 65 is expected to double to 71 million by 2030, health advocates warn.

More money is needed for research and improved therapies, they say.

"We are in the midst of a tidal wave that is going to transform our society," said Peter Braun, executive director of the Los Angeles, Riverside & San Bernardino Counties Chapter of the Alzheimer's Assn.

"It's the silver tsunami that is coming upon us," Braun added.

Alzheimer's, first diagnosed 100 years ago this month, is a progressive and ultimately fatal brain disease for which there is no cure.

It is highlighted by a gradual decline of memory, thinking and reasoning skills.

In the late stages of Alzheimer's, abnormal clumps of proteins are found in the brain as cells continue to be destroyed. Patients on average live about eight to 10 years after they are diagnosed.

Darlene Jordan, 49, who cares for her husband, Charles, 56, said the first sign of trouble came six years ago when the Palmdale couple's young daughter noticed how her father misspelled "Easter." When a neurologist diagnosed Charles with Alzheimer's, the couple sought a second opinion.

That was five years ago. Charles now is experiencing the more severe symptoms of the disease, and must be prompted to chew each bite of food.

"Alzheimer's is not just a senior's disease," his wife said. "People need to not be in denial."

Indeed, it's important that a diagnosis be made as soon as possible so drugs that can delay some symptoms of the disease can be given, said Richard Bozanich, 49, a former journalist diagnosed with Alzheimer's in June but who has had symptoms for two years.

People shouldn't be afraid to talk about the disease, the Rancho Palos Verdes man said. His family had a history of early-onset Alzheimer's, but the family tended to avoid detailed discussions about those who had fallen ill. "It's important people see it can happen to anybody," Bozanich said.

It's also important to know how the disease can affect caregivers because 80% of care is provided by family members, said Debra Cherry, associate executive director of the local chapter of the Alzheimer's association in the Southland. Caregivers often suffer depression and chronic diseases caused by stress.

Without better treatment or a cure, the number of people with Alzheimer's in the United States could triple to about 12 million to 13 million people by 2040, costing $300 billion a year, said Dr. George Bartzokis, a neurologist and director of the UCLA Memory Disorders Clinic.

"By itself, Alzheimer's will bankrupt Medicare unless we do something about treatment and prevention," Bartzokis said.

"We in the brain field need to catch up to do the research … to stave off the disaster."