AIM: This cross-sectional study investigated associations between chronic headache (CH) with and without medication overuse, healthy lifestyle behaviour, and stress.

METHODS: Questionnaires were sent to 129,150 adults. Those with headache ≥15 days per month for three months were classified as having CH then further described as having medication-overuse headache (MOH) or CH without medication overuse. Associations between headache and daily smoking, physical inactivity, obesity, excessive drinking, illicit drug use, and high stress were analysed by logistic regression.

RESULTS: CH with and without medication overuse (prevalence 1.8% and 1.6%, respectively) had strong, graded associations with stress. Associations with daily smoking, physical inactivity, and obesity were significant only for MOH. Odds for MOH were highest among people who had all three factors compared to those who had none (OR 2.8 in women and 5.1 in men). High stress plus any of these three factors had synergistic effects in MOH but not clearly in those who had CH without overuse. Associations between CH subtypes and excessive drinking or illicit drug use were not statistically significant.

CONCLUSION: Results suggest strong links between healthy lifestyle behaviour and stress in MOH. Stress reduction and promoting healthy behaviour are highly relevant in MOH management.