There may be a bidirectional relationship between fibromyalgia and migraine, according to a longitudinal cohort study published in BMJ Open.
For this study, researchers examined data from 2 cohorts in a nationwide health database: 33,216 patients with fibromyalgia (average age, 51.4 years) and 7420 separate patients with migraine (average age, 44.5 years). Patients were age- and sex-matched 4 to 1 with control subjects who had neither migraine nor fibromyalgia.
The incidence of migraine was found to be higher in individuals with vs without fibromyalgia after adjusting for sex, age, and comorbidities (4.39 vs 2.07 per 1000 person-years, respectively; adjusted hazard ratio, 1.89; P <.001). The relative risk for migraine in women and men with fibromyalgia was 1.76 and 2.29, respectively, and this risk was highest in individuals ≤50 years of age (hazard ratio, 2.06).
Factors associated with greater risk for migraine occurrence in the fibromyalgia cohort were male sex, hyperlipidemia, depression, anxiety, sleep disorder, coronary artery disease, chronic fatigue syndrome, and irritable bowel syndrome (P <.05 for all). Incidence of fibromyalgia was greater in individuals with vs without migraine (7.01 vs 4.49 per 1000 person-years, respectively; adjusted hazard ratio, 1.52; P <.001). The relative risk for fibromyalgia in women and men with migraine was 1.43 and 1.78, respectively, and this risk was highest in individuals ≤50 years of age (hazard ratio, 1.64). Age, migraine, hypertension, hyperlipidemia, depression, sleep disorder, and coronary artery disease were associated with reduced fibromyalgia incidence.
Study limitations include potential difficulty in discerning disorders stemming from poor categorization of symptoms.
“The results of comparing the 2 cohort arms suggested a bidirectional risk [for] migraine and fibromyalgia in patients with fibromyalgia and those with migraine, respectively. These results indicated that fibromyalgia had stronger predictive power for the onset of migraine than did migraine for the onset of fibromyalgia,” concluded the study authors.
Penn I-W, Chuang E, Chuang T-Y, Lin C-L, Kao C-H. Bidirectional association between migraine and fibromyalgia: retrospective cohort analyses of two populations. BMJ Open. 2019;9(4):e026581.