Chronic migraine, comorbidity and socioeconomic deprivation: cross-sectional analysis of a large nationally representative primary care database

Abstract

Objectives: To examine mental and physical comorbidities in chronic migraine and the influence of socioeconomic status in a large, nationally representative dataset. Methods: Analysis of cross-sectional primary healthcare data on 1,468,404 adults in Scotland. Data on chronic migraine derived from prescription data, 31 physical, and seven mental health conditions were extracted. Prevalence rates were standardised by age-groups, gender, and neighbourhood deprivation, and odds ratio (OR) and 95% confidence intervals (CI) calculated for those with migraine compared to those without. Results: Those with chronic migraine were significantly more likely to have more conditions, with the biggest difference found for five or more conditions (migraine 11.7% vs. controls 4.9; OR 3.00 95% CI 2.78-3.22). In total, 25 of the 31 physical conditions were significantly more prevalent in the migraine group. The biggest differences after standardisation for age, sex and deprivation was for chronic pain (OR 4.33, 95% CI 4.12-4.55) followed by constipation and dyspepsia. For mental health conditions, the biggest differences after standardisation for age, sex and deprivation was for anxiety (OR 2.95, 95% CI 2.76-31.5) and depression (OR 2.94, 95% CI 2.81-3.08). Increasing deprivation was associated with more severe and complex comorbidity (five or more conditions), and with more combined mental and physical comorbidity in the migraine group compared with the controls group. Conclusions: In a large nationally representative sample in primary care, severe and complex comorbidity was commoner in people with chronic migraine compared with standardised controls, and this was exacerbated by living in areas of higher deprivation. The implications of this for patients and practitioners are discussed.Journal of Comorbidity 2017;7(1):89–9