[oldalum]

A recent meta-analysis of studies of the association of head injury to ALS is here. Remember that association does not prove causation.
The authors' conclusion is: "This meta-analysis indicates that head injury, especially severe head injury, could increase ALS risk."
Interestingly, the strongest association was with head injury less than one year of a diagnosis of ALS, which suggests reverse causation: incipient developing ALS is a strong risk factor for head injury (makes sense).

[oldalum]

A recent meta-analysis of studies of the association of head injury to ALS is here. Remember that association does not prove causation.
The authors' conclusion is: "This meta-analysis indicates that head injury, especially severe head injury, could increase ALS risk."
Interestingly, the strongest association was with head injury less than one year of a diagnosis of ALS, which suggests reverse causation: incipient developing ALS is a strong risk factor for head injury (makes sense).