Risk of developing migraine among patients with posttraumatic stress disorder: A nationwide longitudinal study

Objective: We intended to investigate the risk of developing migraine among patients with posttraumatic stress disorder (PTSD). Methods: With the Taiwan's National Health Insurance Research Database, we examined 5,644 patients with PTSD and 22,576 age- and sex-matched controls between 2002 and 2009 and followed them to the end of 2011. Individuals who developed migraine during the follow-up period were identified. Results: Patients with PTSD had a significantly higher incidence of developing migraine (5.74 vs. 1.22 per 1,000 person-years, p < 0.001) during the follow-up period than the controls. We did Cox regression analysis with adjustments of demographic data and medical comorbidities and found that patients with PTSD were more likely to develop migraine (hazard ratio [HR] = 3.83, 95% confidence interval [CI] = 2.82–5.20) than the control group. Sensitivity analyses after excluding the 1st year (HR = 2.89; 95% CI = 2.04–4.08) or the first 3 years (HR = 2.07; 95% CI = 1.32–3.24) of observation showed consistent findings. Moreover, a high frequency of psychiatric clinics visiting for PTSD was associated with an increased risk of developing migraine. Conclusion: Patients with PTSD had a higher risk of migraine than the controls. The symptom severity of PTSD may be associated with an increased risk of migraine. Further studies are required to investigate the underlying pathophysiology between PTSD and migraine