Greater Severity and Functional Impact of Post-traumatic Headache in Veterans With Comorbid Neck Pain Following Traumatic Brain Injury

Background: Post-traumatic headache (PTH) is a commonly experienced symptom after mild traumatic brain injury (mTBI). Blast injury- or blunt injury-related mechanisms for mTBI in veterans can also affect musculoskeletal structures in the neck, resulting in comorbid neck pain (NP). However, it is unknown whether the presence of comorbid NP may be associated with a different pattern of headache symptoms, physical functioning, or emotional functioning compared to those without comorbid NP. The purpose of this study is to examine the role of comorbid NP in veterans with mTBI and PTH. Design and Methods: This was a cross-sectional investigation of an existing dataset that included 33 veterans who met inclusion criteria for PTH after mTBI. Standardized measures of headache severity and frequency, insomnia, fatigue, mood disorders, and physical and emotional role function were compared between groups with and without comorbid NP. Results: The majority of participants with PTH reported comorbid NP (n=22/33, 67%). Those with comorbid NP experienced more headache symptoms that were severe or incapacitating, as compared to mild or moderate for those without NP (f=0.343, P=.049); however, no differences in headache frequency (f=0.231, P=.231) or duration (f=0.129, P=.712) were observed. Participants with comorbid NP also reported greater insomnia (d=1.16, P=.003) and fatigue (d=0.868, P=.040) as well as lower physical functioning (d=0.802, P=.036) and greater bodily pain (d=0.762, P=.012). There were no differences in anxiety, depression, mental health, emotional role limitations, vitality, or social functioning between those with and without comorbid NP (d=0.656, P=.079). Conclusions: A majority of veterans with mTBI and PTH in our sample reported comorbid NP that was associated with greater headache symptom severity and physical limitations, but not with mood or emotional limitations. Preliminary findings from this small convenience sample indicate that routine assessment of comorbid NP and associated physical limitations should be considered in veterans with mTBI and PTH.