Abstract
This issue of Journal of Neurotrauma features four important articles on long-neglected aspects of traumatic brain injury research: intimate partner violence and neighborhood disadvantage. First off, in three papers, Dr. Karr and colleagues present detailed information on injury characteristics, symptoms, receipt of care, and the correlates of repetitive injuries in a cohort of women from the US state of Kentucky who reported restraining orders against intimate partners. They found that women who reported intimate partner violence-related head injuries had significantly more cognitive, physical, and emotional symptoms than women in the same cohort without reported head injuries. Furthermore, women reporting intimately partner violence-related head injuries also reported more severe ongoing cognitive, physical and emotional symptoms, but lower rates of hospitalization and rehabilitation than women reporting head injuries that were not related to intimate partner violence. Notably, a substantial number of the women reported multiple intimate partner violence-related head injuries; in fact, the mean number of reported injuries was 17, with the range up to 515. Unsurprisingly, greater numbers of injuries was associated with more severe reported symptoms including headaches, dizziness, and sleep problems. These represent important early papers in the field, but much more work remains to be done. The cohort studied by Karr et al. likely represents just a small portion of the spectrum of intimate partner violence-related TBI. Many more individuals of all genders likely suffer intimate partner violence-related TBI but do not report it to health care providers or legal authorities. Major tasks for the field will be to find new approaches to better understand, prevent, and treat this type of interpersonal aggression.
Intimate partner violence is not the only understudied portion of the TBI landscape. Gaudet et al., report striking associations between neighborhood disadvantage and worse outcomes following concussion in adolescents. Neighborhood disadvantage was measured by using the Area Deprivation Index, a combined census data-based measure that includes indices of education, income, poverty, employment, housing status, home ownership, and incomplete plumbing. Return-to-sport were significantly delayed in adolescents living in more disadvantaged neighborhoods in the US state of Maine, with odds ratios of 2.7 and 4.3 for likelihood or return-to-sport at 21 and 28 days respectively compared with those living in less disadvantaged neighborhoods. Again, the findings reported by Gaudet et al. likely represent just the tip of the iceberg in terms of the social determinants of TBI-related health outcomes. Understanding and allocating resources to address these inequities presents a substantial challenge. Also, from a methodological perspective, the use of the Area Deprivation Index, while common is other fields, is relatively novel in the field of neurotrauma. This index may be useful for predicting outcomes and assessing the adequacy of matching between groups in clinical research studies.
Finally, in an intriguing and thematically related paper in Journal of Neurotrauma, Naugle et al., previously reported worse pain-related outcomes- mainly headaches- following “mild” TBI in individuals self-identifying as African American compared with Caucasian. Racial differences were not observed in control individuals without TBI. The effects on headache pain intensity in those with TBI were almost completely mediated by self-reported pain catastrophizing, which was higher in the African American individuals. Pain catastrophizing has been defined in this context as “a negative cognition related to the belief that the experienced pain will inevitably result in the worst possible outcome,” and includes aspects of rumination, helplessness, and pessimism. The underlying causes of racial differences in pain catastrophizing in this context are not known, but hypotheses include effects of structural racism, neighborhood disadvantage, inequities in previous experiences with the health care system, and related social determinants of health. Once again, an enormous amount of additional research will be required to understand and mitigate inequities in pain-related outcomes following TBI.