Mild traumatic brain injury (TBI) may be linked to an increased risk of addiction, a study of military personnel suggests.

Researchers found mild TBI was linked with an increased risk for alcohol dependence, up to 180 days after the injury occurred. They also found an increased risk for nondependent abuse of drugs or alcohol and nicotine dependence in the month after the airmen sustained the injury, News-Medical.net reports.

The study included 5,065 active-duty airmen who suffered a mild TBI that resulted in temporary confusion or disorientation, memory loss, and/or a brief loss of consciousness. They were compared with a group of 44,733 airmen who suffered other types of injuries.

The study found the risk of alcohol dependence was significantly raised in airmen with a mild TBI, compared with those in the comparison group. The risk was greatest soon after the injury occurred, and decreased over time.

The study appears in the American Journal of Psychiatry.

The researchers wrote, “Screening for addiction-related disorders should be considered as part of routine care for mild TBI and might best capture the first 30 days post-mild TBI, with repeat alcohol screening thereafter for at least 6 months following the injury.”