New blood test to help diagnose Alzheimer's

HOUSTON For years, researchers have been looking for a way to diagnose Alzheimer's disease early, before there are symptoms.

"The good news is there's a lot of activity looking at blood tests," said Dr. Rachelle Doody, Director of Baylor Alzheimer's Disease and Memory Disorder Center.

Dr. Doody says they've been working with other Texas researchers on a blood test to find Alzheimer's early. Other blood tests are being developed, too, including one announced yesterday.

"There will be many blood tests for Alzheimer's disease. There will be blood tests that tell us if a person is at risk, but it doesn't tell us if they'll ever get the disease. We already have one test like that. There will be blood tests that tell us if someone has Alzheimer's, but they don't have any symptoms," said Dr. Doody.

She says that's where a blood test will make a big difference -- in giving people a head start on treatment.

"It's just critical that we find a way to detect Alzheimer's disease early, and when we say early, it means before there are any symptoms. This disease develops in the brain decades before there are any symptoms," Dr. Doody said.

But without a cure, some people ask if it's worth getting an early diagnosis. Dr. Doody says yes, and that medicines do delay the progression.

"For some people, you get a relative plateau for years -- two years, five years, seven or eight years," she said.

And new medicines are being developed so that when those better diagnostic tests, perhaps blood tests, are ready for prime time, there will be better medicines to give those patients.

Scientists believe a blood test for Alzheimer's being developed by the Scripps Research Institute is accurate, and it might also be able to diagnose other diseases early as well, including some cancers.