Data gathered by the National Health and Nutrition Examination Survey showed that nearly 16 percent of U.S. adults aged 40 and older answered yes to the question, “Have you ever had loss of consciousness because of a head injury?” Men were nearly twice as likely to have answered yes, about 20 percent compared with 12 percent among women. Further, these head injuries are associated with neurological and psychological problems such as depression, sleep disorders, stroke and alcoholism, the researchers found. People who reported a head injury that knocked them out were 54 percent more likely to have a sleep disorder, 68 percent more likely to have had a stroke, twice as likely to be a heavy drinker, and more than twice as likely to have symptoms of depression.
“I think the numbers are impressive. The numbers are staggering. They certainly support the notion that we need to learn a heck of a lot more about how to prevent this injury. But at the end of the day, I think this is definitely an undercount.” The single question used in this survey does not capture all of the potential scenarios in which a traumatic brain injury could occur, Dams-O’Connor explained. For example, the survey question would not reflect people who were dazed or confused by a blow to the head that did not cause them to lose consciousness, she said. “That would meet the criteria for a mild traumatic brain injury, and none of those people are even included in this estimate,” Dams-O’Connor noted.