The course of headache in patients with moderate-to-severe headache due to mild traumatic brain injury: a retrospective cross-sectional study

Background: Little is known about the long-term course of headache in patients with moderate-to-severe headache due to traumatic brain injury (TBI). We evaluated the course of headache in patients with moderate-to-severe headache due to mild TBI. Methods: Since September 2009, patients with TBI prospectively rated their headache using a numeric rating scale (NRS). From the database containing 935 patients with TBI between September 2009 and December 2013, 259 patients were included according to following criteria: (1) newly onset moderate-to-severe headache (NRS >= 4) due to head trauma; (2) age >= 15 years; (3) Glasgow Coma Scale >= 13; (4) transient loss of consciousness <= 30 min; and (5) radiographic evaluation, such as computed tomography or magnetic resonance image. We evaluated initial and follow-up NRS scores to determine the significance of NRS changes and identified risk factors for moderate-to-severe headache at 36-month follow-up. Results: At 36-month follow-up, 225 patients (86.9%) reported improved headache (NRS <= 3) while 34 (13.1%) reported no improvement. The NRS scores were significantly decreased within a month (P < 0.001). The follow-up NRS scores at 12-, 24-, and 36-months were lower than those at one month (P < 0.001). Multiple logistic regression analysis showed that post-traumatic seizure (odds ratio, 2.162; 95% CI, 1.095-6.542; P = 0.041) and traumatic intracranial hemorrhage (odds ratio, 2.854; 95% CI, 1.241-10.372; P = 0.024) were independent risk factors for moderate-to-severe headache at 36-month follow-up. Conclusions: The course of headache in patients with mild TBI continuously improved until 36-month follow-up. However, 13.1% of patients still suffered from moderate-to-severe headache at 36-month follow-up, for whom post-traumatic seizure and traumatic intracranial hemorrhage might be risk factors.