Head injury associated with increased risk of ALS

Does having a head injury increase the risk of developing amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease), a motor neuron disease? Researchers at the National Institute of Environmental Health Sciences in North Carolina studied 109 individuals with ALS, and 255 people without the disease, to try to answer this question. The study participants were asked if they had ever been injured so severely that they needed medical attention. Of the people with ALS, 46.8% had been injured, and of those without ALS, 45.1% had been injured. Only head injury was associated with an increased risk of developing ALS. These results suggest that head injury might be a risk factor for ALS, but because the number of people surveyed was small, it will be necessary to look at information from more people before any definite conclusions can be drawn.

Chen, Honglei, Marie Richard, Dale P. Sandler, David M. Umbach, & Freya Kamel. "Head Injury and Amyotrophic Lateral Sclerosis." American Journal of Epidemiology 166(2007): 810-816.

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