Association of migraine with subsequent risk of depression or anxiety by small-area deprivation: national cohort study with sibling analysis.

BACKGROUND: Growing evidence indicates that migraine could increase the risk of depression or anxiety in affected persons. Residential deprivation, with its links to stressful environments and access to quality services, could exacerbate the risk of developing depression or anxiety among migraine patients, but evidence remains limited. We aimed to examine the subsequent risk of depression or anxiety in persons with migraine and to determine if this association varies by small-area deprivation. METHODS: A nationwide register-based cohort study was conducted of persons aged 10–50 years registered in Sweden from 2015 to 2023 who did not have recorded depression or anxiety in the previous ten years (n = 4,065,375). We generated matched (n = 1,455,352) and sibling (n = 179,888) samples for analyses. The exposure (migraine) and outcome (depression or anxiety) were defined as the first diagnosis, or the first prescription date if no diagnosis was recorded in the study period. Follow-up started six months after migraine exposure and hazard ratios (HR) for depression or anxiety through 31 December 2023 were computed for the matched and sibling cohorts using stratified cox regression models with robust error variance. We tested for an interaction between small-area deprivation and migraine on the association with depression or anxiety. RESULTS: Incidence rates for depression or anxiety among people with or without migraine in the matched cohort were 39.2 and 21.9 per 1,000 person-years with an adjusted HR of 1.78 (95% CI: 1.75–1.81) across follow-up. In the sibling cohort, the HR of depression or anxiety associated with migraine was 1.63 (95% CI: 1.58–1.68). There was no evidence of an overall interaction between migraine and small-area deprivation on the subsequent risk of depression or anxiety in the matched (p = 0.123) or sibling (p = 0.422) cohorts. CONCLUSIONS: People with migraine have a nearly two-fold higher rate of depression or anxiety than those without migraine, and the association was lower but remained after adjustment for shared genetics or childhood family environments. While small-area deprivation did not modify the relationship between migraine and the risk of depression or anxiety in our cohort, further investigation of this important research question is merited.