Researchers from the study, led by Emmanuel Lagarde, PhD, of the University of Bordeaux in France, publish their findings in JAMA Psychiatry.
The new study suggests symptoms lasting 3 months after a concussion may be PTSD.
But despite its prevalence, medical professionals know little about the course and prognosis of the condition. And this can cause problems for clinicians who are prompted by insurance companies to conclude whether the long-term symptoms are a cause of the injury.
Post-concussion syndrome (PCS) has three areas under which symptoms fall: cognitive, somatic and emotional.
According to the Centers for Disease Control and Prevention (CDC), most people recover quickly and fully from a concussion. For others, however, prolonged symptoms can include: difficulty thinking clearly or concentrating, headache, blurry vision, dizziness, nausea or vomiting, sensitivity to noise or light, irritability, sadness and sleep difficulties.
However, the researchers explain that understanding symptoms after MTBI should include the consideration that injuries are frequently incurred during distressing events, which can lead to post-traumatic stress disorder (PTSD).
'Evidence does not support further use of PCS'
To further investigate, the researchers assessed patients at an emergency department in France to find out whether symptoms lasting 3 months after an injury to the head were specifically related to concussion or whether they could be better classified as PTSD.
In total, the prospective cohort study included 534 patients with head injury and 827 control patients without a head injury, who visited the University Hospital of Bordeaux between December 2007 and February 2009.
Results show that 3 months after the injury, 21.2% of patients with a head injury met the diagnosis of PCS, and 8.8% met the criteria for PTSD. By comparison, 16.3% of patients without a head injury met the diagnosis of PCS, and only 2.2% met the criteria for PTSD.
The researchers say that persistent symptoms reported after a concussion are "not specific enough to be identified as a unique PCS and should be considered part of the hyperarousal dimension of PTSD."
The authors add:
"Further use of PCS in head-injury patients has important consequences, in terms of treatment, insurance resource allocation and advice provided to patients and their families. Available evidence does not support further use of PCS."
They say their study results "also stressed the importance of considering PTSD risk and treatment for patients with MTBI."
Medical News Today recently reported on a study from the University of Kentucky in Lexington that suggested some teens are more susceptible to emotional symptoms than others following a concussion.