Epidemiology and predictors of post-concussive syndrome after minor head injury in an emergency population

Abstract

Objective : To determine if clinical variables or neurobehavioural test (NBT) scores obtained in the ED within 24 hours of minor head injury (MHI) predict the development of postconcussive syndrome (PCS). Methods : Prospective, observational study of 71 MHI patients and 60 orthopaedic controls. MHI defined as loss of consciousness < 10 minutes or amnesia, GCS 15, no skull fracture or new neurologic focality on PE, and no brain injury on CT (if done). All patients received a seven part NBT battery in the ED. Telephone follow-up was done at 1, 3 and 6 months to determine if patients met the DSM IV definition of PCS. Analysis : Stepwise, multivariate, logistic regression. Results : Predictors of PCS at 1 month were female gender (OR 7.8; 95% CI 41.6, 1.98), presence of both retrograde and anterograde amnesia (OR 0.055; CI 0.002, 0.47), Digit Span Forward Scores (OR 0.748; CI 0.52, 1.03) and Hopkins Verbal Learning A scores (OR 0.786; CI 0.65, 0.91); at 3 months, presence of both retrograde and anterograde amnesia (OR 0.13; CI 0.0, 0.93), Digit Span Forward Scores (OR 0.744; CI 0.58, 0.94). No variables fit the model at 6 months. 92% of males scoring > 25 on Hopkins Verbal Learning A did not have PCS at 1 month, and 89% of females scoring < 9 on Digit Span Forward did have PCS at 1 month. Conclusions : Gender and two NBTs can help predict PCS after MHI.