Testing Our Blood for Alzheimer's

You probably know someone who has Alzheimer's because one out of every three elderly Americans die from it. And while heart disease deaths fell more than ten percent the last fifteen years, deaths from Alzheimer's jumped over one hundred percent. If we could diagnose Alzheimer's and dementia earlier, we could not only slow or stop their symptoms but save nearly three hundred billion dollars a year in medical costs, a huge help for burdened families.

One recent study is getting us closer to a blood test to diagnose the disease early. It measures levels of a protein that shows up in the blood when nerve cells in the brain are damaged or die. This protein is called neurofilament light chain or NfL and what's amazing is that measuring changes of this protein in the blood over time can predict future dementia onset up to sixteen years before symptoms appear.

In order to measure Nfl, researchers in the study chose to study people who carry a gene for early onset Alzheimer's and compared them to relatives who don't carry the trait. They took spinal fluid and blood samples from both groups over many years and measured their Nfl levels every one to three years. The Nfl was significantly higher at about seven years before symptoms appeared, but researchers could detect elevated levels nearly seventeen years prior.

The test is far from ready for commercial use since this study only focused on people with genetically acquired Alzheimer's. Researchers will need to see if it works on those who develop Alzheimer's sporadically. If it does work, imagine a yearly physical where a blood test could warn you of dementia decades down the road and what you can do now to change its course. That's powerful!