Comorbid depression or anxiety among migraine patients aged ten years or older living in Sweden in 2015 to 2023: A nationwide study.

BackgroundResidential deprivation is a long-established risk factor for poor health outcomes including migraine, depression and anxiety that are significant public health problems in Sweden and globally. Yet the relationship between residential deprivation and patterns of comorbidity among these three conditions is less understood. We aimed to estimate the magnitude and determinants of comorbid depression or anxiety among migraine patients in Sweden including the relationship between residential deprivation and comorbidity prevalence.MethodsA nationwide register-based cross-sectional study was conducted of persons aged ten years or older in Sweden in 2015-2023. Comorbid depression or anxiety was defined as any depression or anxiety diagnosis or treatment during the migraine-exposed period (from three months before until three months after the first and last recorded migraine exposure in the study period). Small-area deprivation was based on an Index for Multiple Deprivation in Sweden (IMDIS) applied to 5984 small geographic areas. Prevalence ratios (PR) estimated the association between comorbidity and small-area deprivation adjusted for other covariates (age, sex, area of residence, birthplace) using Poisson regression models with robust error variance. We compared sick leave utilization (over fourteen days) for any reason in the migraine-affected years among migraine patients with or without comorbidity.ResultsThere were 372,926 migraine patients in the study, and 35.7% (n = 133,219) had comorbid depression or anxiety. There was higher comorbidity prevalence among migraine patients in the most versus the least deprived areas (PR: 1.18, 95% CI: 1.17-1.20). Although the data have limitations, we found that one-third (31.9%) of migraine patients took sick leave (over fourteen days) for any reason during the migraine-exposed years, which rose to 50.9% among migraine patients with comorbid depression or anxiety.ConclusionsMore than one-third of migraine patients had comorbid depression or anxiety with higher prevalence of comorbidity in the most deprived areas. Common comorbid depression or anxiety among migraine patients underscores the need to consider all three conditions in clinical encounters especially for residents of more deprived residential areas.