The purpose of this analysis was to determine which of the initial symptoms after mild traumatic brain injury (MTBI) can best predict the development of persistent postconcussive syndrome (PCS).
One hundred eighty MTBI patients admitted to a level I trauma center were enrolled in a prospective study and 110 followed for 3 months. MTBI was defined as a Glasgow Coma Score of 13 to 15 with a transient loss of consciousness or report of being dazed or confused. PCS was defined as the persistence of four or more symptoms long term. Patients were screened at admission and at 3 days to 10 days and 3 months. Symptom checklists were administered to ascertain the presence of symptoms (cognitive, emotional, and physical) after concussion. For a subset of patients that were physically able, balance tests were also conducted. Stepwise logistic regression was used to identify which symptoms best predicted PCS.
The mean age of the subjects was 35 years, and 65% were men. Physical symptoms were the most prevalent in the 3 days to 10 days postinjury with most declining thereafter to baseline levels. Emotional and cognitive symptoms were less prevalent but more likely to remain elevated at 3 months; 41.8% of subjects reported PCS at 3 months. The strongest individual symptoms that predicted long-term PCS included anxiety, noise sensitivity (NS), and trouble thinking; reported by 49%, 27%, and 31% of the subjects at 3 days to 10 days, respectively. In multivariate regressions including age, gender, and early symptoms, only anxiety, NS and gender remained significant in the prediction of PCS. Interactions revealed that the effect of anxiety was seen primarily among women. NS had an odds ratio of 3.1 for PCS at 3 months.
After MTBI, anxiety among women and NS are important predictors of PCS. Other physical symptoms, while more prevalent are poor predictors of PCS.