Head Injury and Amyotrophic Lateral Sclerosis

Honglei Chen1, Marie Richard2, Dale P. Sandler1, David M. Umbach3 and Freya Kamel1
1 Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
2 Westat Inc., Durham, NC
3 Biostatistics Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC

Correspondence to Dr. Honglei Chen, Epidemiology Branch, National Institute of Environmental Health Sciences, 111 T. W. Alexander Drive, P.O. Box 12233, Mail Drop A3-05, Research Triangle Park, NC 27709 (e-mail: chenh2@niehs.nih.gov).

Received for publication December 28, 2006. Accepted for publication April 23, 2007.

Recent data showed that soccer players in Italy had an unusually high risk of amyotrophic lateral sclerosis (ALS) and that repeated head trauma might have contributed to this increase. The authors examined whether head injury was related to ALS risk in a case-control study of 109 New England ALS cases diagnosed in 1993–1996 and 255 matched controls. They also conducted a meta-analysis of the published literature. Overall, ever having experienced a head injury was nonsignificantly associated with a higher ALS risk. When compared with persons without a head injury, a statistically significant ALS risk elevation was found for participants with more than one head injury (odds ratio (OR) = 3.1, 95 percent confidence interval (CI): 1.2, 8.1) and patients who had had a head injury during the past 10 years (OR = 3.2, 95 percent CI: 1.0, 10.2). For participants who had had multiple head injuries with the latest occurring in the past 10 years, risk was elevated more than 11-fold. The meta-analysis also indicated a moderately elevated risk of ALS among persons with previous head injuries (OR = 1.7, 95 percent CI: 1.3, 2.2). In this study population, physical injuries to other body parts, including the trunk, arms, or legs, were not related to ALS risk. These data support the notion that head injury may increase the risk of ALS.


amyotrophic lateral sclerosis; craniocerebral trauma; head injuries, closed; head injuries, penetrating


Abbreviations: ALS, amyotrophic lateral sclerosis; CI, confidence interval; OR, odds ratio; SOD1, superoxide dismutase 1
http://aje.oxfordjournals.org/cgi/co...short/kwm153v1