New blood test can detect early signs of ALS, study finds

A new study from the National Institutes of Health found signs of amyotrophic lateral sclerosis, or ALS, can be found in blood samples. 

To diagnose ALS now, doctors rely on symptoms and neurological tests. The study findings could help lead to early detection. 

Blood test for ALS

Big picture view:

Researchers from various departments of the institute found certain proteins in blood can accurately detect ALS long before symptoms emerge. 

For context :

Many doctors struggle to confirm the diagnosis before symptoms get severe, and people with ALS often die within 2 to 4 years after symptoms start – bringing a critical need for early detection, according to NIH. 

By the numbers:

The study team found 33 proteins that distinguish ALS from other neurological conditions. Only two of those proteins had been linked to ALS before. 

Dig deeper:

Researchers did this by analyzing more than 3,000 proteins found in blood samples from ALS patients. They compared the protein data to samples from healthy people and those with other neurological conditions, and developed a predictive model for identifying ALS that could diagnose ALS with more than 98% accuracy. 

In short:

The findings suggest it’s possible to detect ALS in a simple blood test and distinguish it from other clinically relevant conditions, NIH said. 

And the discovery may offer the first definitive ALS diagnostic test and a potentially promising way to track disease progression in clinical trials.

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What is ALS? 

Big picture view:

In ALS, misfolded proteins in motor neurons cause progressive muscle weakness and paralysis, according to NIH. Most people with ALS eventually lose the ability to walk, dress, write, speak, swallow and breathe, and their life span is shortened, according to the ALS Association.

ALS can affect anyone at any time, and initial symptoms can be quite varied. 

ALS is also commonly known as Lou Gehrig’s disease, after the famous baseball player who was diagnosed in the 1930s. 

By the numbers:

Although no one knows for sure, the U.S. Centers for Disease Control and Prevention says reports suggest less than 30,000 people in the U.S. have ALS.