Perceived triggers of primary headache disorders: A meta-analysis.

Objective To quantitatively synthesize extant literature on perceived triggers of primary headache disorders. Methods A meta-analytic review of headache trigger survey studies was conducted. Endorsement rates, assessment method, and headache and sample characteristics were extracted from included articles. Separate random-effects models were used to assess trigger endorsement rates and post-hoc meta-regressions examined potential moderator variables. Results 85 articles from 1958 to 2015 were included, involving 27,122 participants and querying 420 unique triggers (collapsed into 15 categories). Four-fifths (0.81; 95% CI .75 to .86) of individuals with migraine or tension-type headache endorsed at least one trigger. Rates increased with the number of categories queried (OR: 1.18, 1.08-1.30) and year of publication (OR: 1.04, 1.00-1.08). The triggers most commonly endorsed were stress (.58, .53-.63) and sleep (.41, .36-.47). Conclusions Extreme heterogeneity characterizes the headache trigger literature. Most individuals with a primary headache disorder perceive their attacks to be triggered by one or more precipitants, the most common of which are stress and sleep. However, trigger endorsement is influenced by method of assessment. Enhancing methodological consistency and prioritizing experimental studies would improve our understanding of headache triggers.