Brain Trauma May Play a Role In Amyotrophic Lateral Sclerosis
In the majority of patients who develop Amyotrophic Lateral Sclerosis, ALS or Lou Gehrig’s Disease, the cause is unknown. Scientists however are increasingly linking head injuries from contact sports to ALS and other neurodegenerative disorders. Some scientists now believe that Lou Gehrig himself may not have had the genetic form of the disorder, but may have developed ALS due to brain trauma.
Amyotrophic Lateral Sclerosis Versus Chronic Traumatic Encephalomyopathy
Amyotrophic Lateral Sclerosis is a disease of the nerve cells in the brain and spinal cord that control voluntary muscle movement. Patients with ALS have a loss of muscle strength and coordination that progresses until they are unable to do routine tasks such as getting out of a chair or swallowing. Death often occurs within 3 to 5 years after diagnosis.
It is estimated that ALS affects approximately 1 out of every 100,000 people.
In a new study, published this week in the Journal of Neuropathology and Experimental Neurology, researchers from Boston University examined the donated brains and spinal cords of 12 deceased athletes. Three had developed a motor neuron disease (MND) with symptoms similar to ALS. Two were actually diagnosed as having Lou Gehrig’s disease. Seven were former football players, 4 had been boxers, and one played professional hockey. All had a history of multiple concussions.
The scientists found that 3 of the patients, two football players and one boxer, did not meet the criteria for ALS and actually died of chronic traumatic encephalomyopathy (CTE), a degenerative brain condition linked to head trauma.
Two specific proteins distinguish CTE from ALS: tau protein and TDP-43. The brains of all 12 athletes had a build-up of abnormal tau protein, but in three patients, the spinal cord also contained abnormal tau, which is not characteristic of sporadic ALS, the most common form of the disorder. Ten of the 12 athletes had another abnormal protein associated with ALS called TDP-43, but the amount was more extensive in the three athletes now diagnosed with CTE.
The suspicion that ALS might be triggered by traumatic brain injury first appeared in medical literature more than 100 years ago. More recently, a study of 7325 professional soccer players in Italy found that ALS was 6.5 times higher than expected.
As for Lou Gehrig, scientists will not be able to test his remains using this new information. Mr. Gehrig was cremated. However, study co-author Dr. Robert Cantu said that the athlete sustained at least five documented concussions during his career. Reports say that in at least one, he was unconscious for five minutes after being struck in the head with a ball. He also played football (halfback) in high school and at Columbia University before his baseball career with the New York Yankees.