|Perhaps even Lou Gehrig had the related syndrome, but that will never be known because he was cremated. (AP File July 1939)|
Multiple head injuries may spur ALS-type illness
New research suggests that athletes who have had multiple head injuries, and possibly others such as military veterans exposed to repetitive brain traumas, may be prone to developing a disabling neurological disease similar to amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig’s disease.
A team of researchers from Boston University School of Medicine and the Veterans Administration Hospital in Bedford said yesterday they have pinpointed evidence of a new disease that mimics ALS in the brains of two former National Football League players previously thought to have died of ALS. They also found the new disease in the brain of a deceased professional boxer who was a military veteran.
In most cases, ALS strikes people — many in the prime of life — with no apparent rhyme or reason. The progressive nerve disorder, which affects an estimated 30,000 Americans, slowly paralyzes patients while leaving their mind intact. But if this early research is borne out by autopsies of additional athletes and veterans, it would support the idea that an ALS-type illness can be triggered by the traumas of sports and war.
“We believe that these three cases are the tip of the iceberg,’’ said neurosurgeon Robert Cantu, who is a codirector of the BU Center for the Study of Traumatic Encephalopathy. “We don’t know whether this is linked to the increased incidence of ALS in the military, who are subject to blasts and other head injuries, but we are concerned that it may be.’’
The findings, the authors speculated, could mean that athletes and some others previously diagnosed with ALS actually had the related syndrome — perhaps even Gehrig himself, the
Scientists not connected with the study said that while the findings are intriguing, they would need to be replicated in a much larger number of people before definitive conclusions could be made.
The Boston researchers studied the brains of 12 former athletes that were donated to the center after their death. All 12 showed signs of a degenerative brain disease, known as chronic traumatic encephalopathy, or CTE, that is believed to be caused by repetitive blows to the head, including concussions.
The researchers previously linked CTE to depression, erratic behavior, and early dementia in a number of former pro athletes, including several football players, who had a history of head injuries.
The researchers found that all athletes with CTE who were examined after death had deposits of an abnormal protein, called tau, in their brain.
In the latest study, they examined three of the former athletes with CTE who were also thought to have died of ALS. All three brains and spinal cords had tau — a protein that is not typically found in ALS patients. That led the researchers to conclude that the tau protein was causing ALS-like symptoms in some patients with CTE.
The three athletes included former
The study is not the first to link head traumas and ALS-type illness. A study of former professional soccer players in Italy found they were 6.5 times more likely to have ALS than the general population. An increased incidence has also been reported among football players in this country. And among veterans with a history of head injuries, the risk of ALS has been pegged at 2.3 times higher than normal, prompting the US Department of Veterans Affairs in 2008 to begin compensating the vets and their survivors for the disease.
“There have been theories proposed about why these clusters have an increased risk of ALS, people were thinking that there may be some sort of neurotoxin these groups were exposed to,’’ said BU associate neurology professor Robert Stern, a codirector of the CTE center and coauthor of the study.
“We are now saying that another theory may be repetitive head trauma’’ is causing the newly identified ALS-type disease, Stern said. “We want to be able to understand these diseases from a very fundamental basis so we can hopefully prevent them, and treat and cure them.’’
The researchers said they were not suggesting that athletes refrain from contact sports, but were trying to highlight the potential long-term risks of head injuries. Their earlier work linking head injuries to CTE prompted rules changes regarding concussions in the NFL and a $1 million pledge from the league to fund their future research — money that helped pay for their latest study.
Dr. Martina Wiedau-Pazos, an associate neurology professor and codirector of the ALS Clinic and Research Center at UCLA, who was not involved with the study, said the findings were based on too few patients to draw definitive conclusions. But she said it does spur new avenues for research on ALS and related disorders.
“Researchers who have been examining postmortem tissue in ALS have been looking at the spinal cord,’’ she said, “but this study now also points to the importance of looking at the brain and the spinal cord.’’
The Massachusetts chapter of the ALS Association echoed that sentiment.
“This is very interesting and exciting research. However, we feel there are too few cases to come to any definitive conclusions and more research needs to be done,’’ said chapter spokeswoman Jen Natoli.
The study is published in the September issue of the Journal of Neuropathology and Experimental Neurology.
Kay Lazar can be reached at firstname.lastname@example.org.