The Association between Serum Total Bilirubin and Severe Headaches or Migraine in American Adults

Background: Studies about the association between bilirubin and migraine were few. Therefore, the purpose of this study was to investigate the association between serum total bilirubin and the prevalence of severe headaches or migraine. Methods: A multivariable logistic regression was used to assess the association between serum total bilirubin concentration and severe headaches or migraine. We also performed stratified analyses, interaction analyses and multiple interpolations in the sensitivity analysis. Results: This cross-sectional study included 12,552 adults from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004. The overall incidence of migraine was 19.99% (2,509/12,552). With every 1 mg/dl increase in bilirubin, the prevalence of migraine decreased by 23% (95% CI: 0.64, 0.93) after adjustment of all related covariates. Similarly, the risk of migraine was reduced by 17% (95% CI: 0.72, 0.97) in the Q4 group (the fourth quartile, highest serum total bilirubin level) compared with the Q1 group (the lowest level). Furthermore, interaction effects by age groups were significant in this relationship (P for interaction = 0.0004). In the Q4 group compared with Q1, inverse associations were observed in those aged ≥40 years (OR: 0.71,95% CI: 0.59, 0.85) in the stratified analysis. Conclusion: These findings support an association between serum total bilirubin and severe headaches or migraine, revealing an inverse association between serum total bilirubin quartiles and severe headaches or migraine in American adults. Age could play an important role in this association.