More than 6 million Americans live with Alzheimer’s disease, according to the Alzheimer’s Association,
Alzheimer’s Disease Facts and Figures, an annual report released by the association, notes that 1 in 3 seniors die with Alzheimer’s or another type of dementia, which means that these issues kill more people than breast and prostate cancer combined. The lifetime risk for Alzheimer’s at age 45 is 1 in 5 for women and 1 in 10 for men.
However, there’s new reason for hope in the fight against Alzheimer’s.
Recent studies found that identifying certain vision problems and testing blood for a protein called phosphorylated tau (p-tau) help doctors detect the disease early, according to The Washington Post and CNN.
How do vision problems relate to Alzheimer’s?
One of the studies noted that an Alzheimer’s variant called posterior cortical atrophy, or PCA, doesn’t affect the body the same as other variants. PCA causes gradual and progressive degeneration of the cortex (the outer layer of the brain) in the posterior (the part of brain located at the back of head), per the Alzheimer’s Association.
Early symptoms of PCA include difficulties with reading and driving, according to The Washington Post.
Since PCA begins by affecting vision, rather than memory, many individuals go years before receiving the correct diagnosis. On average, PCA is not diagnosed until four years after the onset of symptoms. Sixty percent of those diagnosed are women, The Washington Post reported.
The PCA variant begins affecting patients at the age 59, five to six years earlier than those with the common form of Alzheimer’s. Though the number of patients with PCA has not been established, the variant may account for 10% of all Alzheimer’s cases, according to a study published in Lancet Neurology.
While there is no cure for PCA, occupational therapy and other services for visual impairment can help patients. Lifestyle changes such as reading large-print books, using better lighting, and highlighting the boundaries of uneven surfaces are beneficial, per The Washington Post.
How can a blood test screen for Alzheimer’s?
A new blood test that screens for p-tau, a harmful protein found in Alzheimer’s patients, could be used to detect the risk of the disease with high accuracy before symptoms begin to show, according to CNN.
Previously, to identify the buildup of harmful proteins in the brain, patients would have to undergo a brain scan or spinal tap. This new, more accessible test was found to be 97% accurate in identifying p-tau, according to a study published in JAMA Neurology.
The study is no surprise as the scientific community has known that using blood tests have the potential to assess Alzheimer’s disease risk, said Nicholas Ashton, a professor of neurochemistry at the University of Gothenburg in Sweden, to CNN in an email.
Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Florida, told CNN, “This is actually the test that has, at this time, among the best available evidence for being one single test for Alzheimer’s. This study takes us one really powerful step closer to having that test, and the beauty of this study is it also looked at people before they had symptoms.”