Citations

Abstract Objectives/Background To investigate disruptions in resting state networks in participants with acute posttraumatic headache (PTH) due to mild traumatic brain injury (mTBI). Neuroimaging studies have demonstrated alterations in functional connectivity (FC) within core resting‐state networks in participants with headache versus healthy controls (HCs), which may provide insights into disease mechanisms; however, the extent to which these alterations relate to PTH remains incompletely understood. Methods In this comparative cross‐sectional study with an embedded prospective cohort, participants with acute PTH and HCs were enrolled from the Mayo Clinic Arizona and Minnesota, and the Phoenix Veterans Affairs Health Care between 2020 and 2024. Participants with PTH underwent resting‐state magnetic resonance imaging within 2 months following mTBI. We investigated differences within and between functional brain networks in participants with PTH compared to HCs. Associations between altered FC with headache frequency, alterations of mood, post‐mTBI symptoms, and concussion history were determined and corrected for age and sex. Relationships between PTH outcomes at 3 months and baseline FC were investigated. Results Ninety‐six participants with acute PTH (35 male, 61 female) and 84 age‐balanced HCs were included. Decreased resting state network connectivity in participants with PTH compared to HCs (False Discovery Rate (FDR) corrected <0.05) was observed in two default mode network (DMN) regions encompassing the bilateral frontal and anterior cingulate cortex (ACC), as well as the left postcentral gyrus. Within those DMN regions, exploratory analyses revealed that FC was positively associated with headache frequency in the bilateral ACC, right precuneus and frontal gyrus, and with trait anxiety in the right ACC. In contrast, negative associations were observed between FC and number of mTBIs, as well as state anxiety, in the left ACC (uncorrected, p <0.05). No significant associations with clinical headache variables were observed in the DMN comprising the left postcentral gyrus. Baseline group differences in network connectivity between recovered and nonrecovered participants were found in visual, sensorimotor, default mode, executive control and salience networks. Alterations in baseline connectivity between independent components in recovered and nonrecovered participants were not statistically significant after corrections for multiple comparisons. Conclusion In participants with PTH, the DMN regions showing decreased connectivity also exhibited associations with headache frequency, state and trait anxiety, and number of lifetime mTBIs, suggesting that these changes relate to the severity and persistence of post‐mTBI symptoms. The baseline differences in network connectivity between recovered and nonrecovered participants were not statistically significant after corrections for multiple comparisons, indicating that baseline network connections may not play a significant role in the recovery process.

Abstract Objectives/Background Our objectives were to characterize the geographic distribution and local availability of United Council for Neurologic Subspecialties‐certified headache specialists across US counties, hospital referral regions, and states, and to examine associations with socioeconomic deprivation, social vulnerability, and urbanicity. Headache disorders are highly prevalent and disabling, yet local availability of certified headache subspecialty care in the United States remains uneven. Although prior studies have described national and state‐level distributions of United Council for Neurologic Subspecialties‐certified headache specialists, important gaps remain in understanding county‐level availability and disparities in access. Prior state‐level summaries may mask within‐state differences in access to United Council for Neurologic Subspecialties‐certified headache specialists. Methods We conducted a cross‐sectional geospatial workforce analysis of United Council for Neurologic Subspecialties‐certified headache specialists in the United States as of January 7, 2026. Practice locations were mapped to counties, hospital referral regions, and states, and compared with general neurologist supply from the National Provider Identifier registry. Estimated population need was calculated by applying a national migraine prevalence to adult population denominators. We examined associations between specialist distribution and county‐level socioeconomic vulnerability, urbanicity, and region. Results Among 3144 US counties, 2870 (91.3%) had no United Council for Neurologic Subspecialties‐certified headache specialists, and 2085 (66.3%) had no neurologists. Headache specialists were entirely absent from counties without neurologists. Median county‐level headache specialist density was 0 per 100,000 adults, reflecting the absence of local subspecialty care in most US counties. Accounting for county adult population, neurologist density, urbanicity, and region, higher Area Deprivation Index and Social Vulnerability Index scores were associated with lower headache specialist rates. Each 10‐point increase in Area Deprivation Index was associated with lower expected headache specialist rate (adjusted incidence rate ratio = 0.87, 95% confidence interval = 0.82–0.93), and each 0.1‐unit increase in Social Vulnerability Index was also associated with lower expected rate (adjusted incidence rate ratio = 0.94, 95% confidence interval = 0.90–0.98). Headache specialist availability relative to estimated population need varied markedly across counties, with substantial estimated local differences between migraine burden and certified subspecialty supply that were not apparent in state‐level summaries. Conclusion United Council for Neurologic Subspecialties‐certified headache specialists are unevenly distributed across the United States, with limited local availability of certified headache subspecialty care in socioeconomically disadvantaged and nonmetropolitan counties. County‐level analyses identified substantial local gaps in certified headache subspecialty availability that were not apparent in state‐level summaries.