1. 2018;21;E149-E156Association of Higher Migraine Risk Among Female and Younger Chronic Osteomyelitis Patients: Evidence from a Taiwan Cohort of One Million
   Retrospective Study
   Jiunn-Horng Chen, MD, PhD, Shih-Chi Wu, MD, Chih-Hsin Muo, MSc, Chia-Hung Kao, MD, Chun-Hung Tseng, MD, and Chon-Haw Tsai, MD, PhD.

BACKGROUND: Inflammation may trigger migraine development through neurovascular reactions in the brain. Most of the migraine patients, particularly the younger ones, do not have any risk factors for this disease. Hence, we assessed whether chronic osteomyelitis (COM), a chronic inflammatory disease, increases the risk of migraine.

OBJECTIVE: We aim to evaluate the risk of migraine among female and middle-age COM patients with a large patient sample.

STUDY DESIGN: A retrospective cohort study was conducted in this study.

SETTING: The data used in this study were extracted from the Taiwan National Health Insurance (NHI) Research Database.

METHODS: A study group with 2,012 COM patients and 8,048 randomly chosen gender- and age-matched controls were chosen from the Taiwan NHI Research Database (NHIRD) from the start of 2000 to the end of 2009. The risk of migraine was estimated with Cox proportional regression model. Both COM and control groups were followed-up until the occurrence of migraine during the study period (2000–2011). Prevalent covariates, such as age, gender, hypertension, diabetes, hyperlipidemia, stroke, coronary artery disease, depression, anxiety, sleep disorder, bipolar disorder, and epilepsy, were included for further evaluation. The hazard ratio (HR) of migraine was measured with Cox proportional hazard regression model. The primary outcome was the overall migraine risk among COM patients, and the secondary outcome was the migraine risk among COM patients lacking the comorbidities. Additional outcomes included migraine risk among COM patients in different age and gender subgroups.

RESULTS: The overall migraine risk was increased in COM patients (adjusted hazard ratio [aHR] 1.74, 95% confidence interval [CI] 1.14–2.65). Even without any prevalent comorbidities, COM patients still exhibited an increased risk of migraine (aHR 2.05, 95% CI 1.06–3.97) than the controls did. Moreover, this risk was relatively higher in COM patients aged < 40 and 45–54 years (aHR 2.07, 95% CI 0.97–4.46 and aHR 2.11, 95% CI 0.97–4.57, respectively) than in their counterparts. Female COM patients had a relatively higher migraine risk (aHR 1.85, 95% CI 1.05–3.24) than male patients did (aHR 1.68, 95% CI 0.89–3.16).

LIMITATIONS: The messages about personal behaviors were unavailable in the Taiwan NHIRD. Other neurovascular risk factors that might increase migraine cannot be excluded completely in this research.

CONCLUSION: An association between COM and increased risk of migraine was shown in this study. The results suggest that COM is a significant migraine predictor, and thus imply the necessity for rigorous migraine prevention in COM patients, especially female and younger ones.

KEY WORDS: Inflammation, migraine, chronic osteomyelitis, Taiwan National Health Insurance Research Database