Long-term effects of head injuries sustained during life in three male populations.

Data on defined head injuries, suffered during life, were related to possible long-term sequelae among 1112 men aged 30, 50, or 60 years who were sampled from the general population of Gothenburg, Sweden. There was a significant relationship between closed-head injury associated with reported impaired consciousness and occurrence of symptoms of the postconcussional type, self-assessed health variables, and the performance of finger-tapping and reaction-time tests. There was a cumulative effect of repeated head injuries: the more head injuries that were suffered, the more symptoms and more inferior performance were noted. Age at the time of the accident did not influence the occurrence of reported sequelae. Alcohol intake and smoking were powerful factors confounding the postinjury picture, but after taking these factors into account the results were generally the same. The study indicates that head injuries with impaired consciousness, no matter how short, are capable of causing permanent sequelae.