Most of the earlier studies followed participants for only six months after they had experienced TBI, “because it was assumed that the effect after TBI might wear off after a longer time,” Imbach told Live Science.
“However, we have learned from this study that sleep problems persist up to 18 months after TBI,” he said.
The researchers also noted that people with TBI tended to be inaccurate when recording and reporting their own sleep patterns. This is cause for concern, because sleep disruption can have a serious impact on how a person functions when they’re awake, the researchers said.
“The reason for this sleep misperception is unknown, but we plan to investigate in this direction,” Imbach said.
TBIs, mild or severe, affect 1.7 million people in the U.S. each year, the study authors reported. The injuries were associated with 2.5 million hospitalizations, visits to the emergency room or deaths in 2010, according to the CDC.