Scientists are still working toward a long-sought goal—a blood test to identify possible signs of Alzheimer’s and other diseases

Scientists are close to reaching a long-sought goal—a blood test to identify possible signs of Alzheimer’s and other diseases of the brain.
    This comes as a recent large study shows healthy behavior can cut a person’s risk of developing such conditions, even if they have genes that raise that risk.
    At the Alzheimer’s Association International Conference on July 15, six research groups presented new results on several experimental tests. These included one that appears to be 88 percent accurate at identifying Alzheimer’s risk.
    Doctors are hoping for something to use during regular exams that can measure most signs of brain-destroying diseases. They could make better decisions about which patients need additional testing. Current tools such as brain scans and spinal fluid tests are too costly or difficult to do during regular meetings with patients.
    "We need something quicker...It doesn’t have to be perfect," said Maria Carrillo, chief science officer for the Alzheimer’s Association.
    Richard Hodes, director of the National Institute on Aging, called the new results "very promising." He said blood tests soon will be used to choose and observe people for federally-supported studies.
    "This has happened... far faster than any of us would have expected," he told the Associated Press.
    About 50 million people worldwide have the brain disease known as dementia. Alzheimer’s is the most common kind. There is no cure. Current medicines just temporarily ease its harmful effects. Many hoped-for treatments have failed. Doctors think past studies may have included people at too late a stage in the disease, when brain damage was already severe. The experts also say the research may have included too many people with problems other than Alzheimer’s.
    A blood test—rather than subjective estimates of thinking skills—could get the right people into the right studies sooner.
    Researchers at the conference also presented a new study about prevention of these diseases. It showed that people with high genetic risk and poor health habits were about three times more likely to develop dementia than those with low genetic risk and good habits. And, with any level of genetic risk, a good diet, regular exercise, limited alcohol use and no tobacco use made dementia less likely.