It's here: The first blood test to help diagnose Alzheimer's disease is now on sale in the US. It hasn't actually been approved by the FDA; the AP reports it's instead being sold under "more general rules for commercial labs." Even so, it could fill a huge gap in the diagnosis journey for a person suffering from cognitive decline. Many things can cause it, and in order to determine whether Alzheimer's is to blame, a person must have symptoms alongside the buildup of a certain protein in the brain. Currently, the best way to diagnose Alzheimer's, the most common form of dementia, is to measure the protein via a PET brain scan—a diagnostic tool not available to most people, as it is not typically covered by insurance and can cost around $5,000. That means many people can be left without answers.
The blood test, developed by C2N Diagnostics in St. Louis, is also not covered by insurance or Medicare, but its $1,250 cost can be discounted based on income. It's intended only for those over 60 who are already being evaluated for Alzheimer's. While the disease can't be cured, earlier diagnosis can lead to treatments that prolong patients' ability to function independently, Axios reports. "You can’t treat the disease without being able to diagnose it," one researcher said over the summer. "And accurate, low-cost diagnosis is really exciting, so it’s a breakthrough." However, some researchers are concerned that no data has yet been published on the test's accuracy. (Read more Alzheimer's Disease stories.)