News that Robin Williams had been grappling with a diagnosis of Parkinson’s disease before ending his life has sparked increased interest in the disorder this week. And that’s coincided with a fast-rising awareness of a similar disease — amyotrophic lateral sclerosis, or ALS — due to the Ice Bucket Challenge, a fundraising campaign that’s swept social media recently, prompting everyone from Ethel Kennedy to Justin Timberlake to dump freezing water over their heads in the name of research. (And it’s worked, raising millions for the cause.) So how closely linked to Parkinson’s is ALS? Both are progressive neurodegenerative diseases, and neither has a cure. But beyond that, the differences are vast.
“Both occur because some cells in the brain degenerate, and both are diseases of the motor system, meaning they affect how someone moves,” Dr. U. Shivraj Sohur, a movement disorder specialist with the Mass General Institute for Neurodegenerative Disease, told Yahoo Health. “From there, the separation happens quickly, both from a neurology point of view and from a patient’s experience.”
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While ALS is currently getting perhaps its biggest publicity boost since baseball player Lou Gehrig’s suffering made it part of the public lexicon in 1939, Parkinson’s has consistently been in the sphere of public knowledge. And much of that, Sohur said, is due to “sheer numbers.” Currently, an estimated 30,000 Americans are living with ALS and about 5,600 are diagnosed each year. Meanwhile, the number of those living with Parkinson’s is closer to 1 million, which translates to about 60,000 diagnoses a year. Funding for each disease tends to reflect those numbers — according to the National Institutes of Health, ALS public funding in 2013 totaled $39 million, while public funds for Parkinson’s hit $135 million.
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“Awareness is an important thing,” Jim Beck, PhD, vice president of scientific affairs for the Parkinson’s Disease Foundation, told Yahoo Health, “as is scientific research.” He stressed that breakthroughs for either could very well inform the other, as well as myriad other neurological disorders, and added, “You never know where it could lead.” To that end, we’ve broken down the details on both diseases:
ALS (Lou Gehrig’s disease)
What it is: The progressive disease results from a degeneration of motor neurons until those neurons die off, Sohur explained. “Two groups are affected — a group of cells on top of the brain, on the cortex,” he said, “and those within the spinal cord.” Amyotrophic comes from Greek, the ALS Association explains on its website, with “A” meaning no or negative, “myo” referring to muscle, and “trophic” meaning nourishment, so “No muscle nourishment.” When a muscle has no nourishment, it atrophies, or wastes away.