Characteristics and Gender Differences of Headache in the Veterans Health Administration: A National Cohort Study, Fiscal Year 2008–2019

BACKGROUND AND OBJECTIVES: To determine gender differences in headache types diagnosed, sociodemographic characteristics, military campaign and exposures, and health care utilization among US veterans in the Veterans Health Administration (VHA). METHODS: This study used a retrospective cohort design to examine VHA electronic health record (EHR) data. This cohort includes veterans who had at least 1 visit for any headache between fiscal years 2008 and 2019. Headache diagnoses were classified into 8 categories using International Classification of Disease, Clinical Modification codes. Demographics, military-related exposures, comorbidities, and type of provider(s) consulted were extracted from the EHR and compared by gender. Age-adjusted incidence and prevalence rates of medically diagnosed headache disorders were calculated separately for each type of headache. RESULTS: Of the 1,524,960 veterans with headache diagnoses included in the cohort, 82.8% were men. Compared with women, men were more often White (70.4% vs 56.7%), older (52.0 ± 16.8 vs 41.9 ± 13.0 years), with higher rates of traumatic brain injury (2.9% vs 1.1%) and post-traumatic stress disorder (23.7% vs 21.7%), and lower rates of military sexual trauma (3.2% vs 33.7%; p < 0.001 for all). Age-adjusted incidence rate of headache of any type was higher among women. Migraine and trigeminal autonomic cephalalgia rates were most stable over time. Men were more likely than women to be diagnosed with headache not otherwise specified (77.4% vs 67.7%) and have higher incidence rates of headaches related to trauma (3.4% vs 1.9% [post-traumatic]; 5.5% vs 5.1% [postwhiplash]; p < 0.001 for all). Men also had fewer headache types diagnosed (mean ± SD; 1.3 ± 0.6 vs 1.5 ± 0.7), had fewer encounters for headache/year (0.8 ± 1.2 vs 1.2 ± 1.6), and fewer visits to headache specialists (20.8% vs 27.4% p < 0.001 for all), compared with women. Emergency department utilization for headache care was high for both genders and higher for women compared with men (20.3% vs 22.9%; p < 0.001). DISCUSSION: Among veterans with headache diagnoses, important gender differences exist for men and women veterans receiving headache care within VHA regarding sociodemographic characteristics, headache diagnoses, military exposure, and headache health care utilization. The findings have potential implications for providers and the health care system caring for veterans living with headache.