The objective was to examine potential trigger factors of migraine and tension-type headache (TTH) in clinic patients and in subjects from the population and to compare the patients' personal experience with their theoretical knowledge. A cross-sectional study was carried out in a headache centre. There were 120 subjects comprising 66 patients with migraine and 22 with TTH from a headache outpatient clinic and 32 persons with headache (migraine or TTH) from the population. A semistructured interview covering biographic data, lifestyle, medical history, headache characteristics and 25 potential trigger factors differentiating between the patients' personal experience and their theoretical knowledge was used. The most common trigger factors experienced by the patients were weather (82.5%), stress (66.7%), menstruation (51.4%) and relaxation after stress (50%). The vast majority of triggers occurred occasionally and not consistently. The patients experienced 8.9±4.3 trigger factors (range 0-20) and they knew 13.2±6.0 (range 1-27). The number of experienced triggers was smallest in the population group (p=0.002), whereas the number of triggers known did not differ in the three study groups. Comparing theoretical knowledge with personal experience showed the largest differences for oral contraceptives (65.0 vs. 14.7%, p<0.001), chocolate (61.7 vs. 14.3%, p>0.001) and cheese (52.5 vs. 8.4%, p<0.001). In conclusion, almost all trigger factors are experienced occasionally and not consistently by the majority of patients. Subjects from the population experience trigger factors less often than clinic patients. The difference between theoretical knowledge and personal experience is largest for oral contraceptives, chocolate and cheese.

Based on an overview of the literature, this contribution critically discusses the importance of non-alimentary trigger factors of migraine and tension-type headache. Menstruation, environmental factors, psychological effects as well as sleep disorders and fatigue are mentioned most frequently. According to controlled studies, menstruation is indubitably associated with an increased risk of headache. Although a correlation between specific meteorological parameters and the appearance of headaches was established in some patients, the subjective observations of the patients did not however correlate with the objective weather data. Sensory stimuli function as triggers particularly for migraine with aura. Psychological factors, especially stress and everyday pressures, have been confirmed as trigger factors, but further prospective trials addressing this issue would be advantageous. Additional studies are also needed to elucidate the significance of sleep (disorders) and fatigue since their importance as triggers or symptoms of a headache attack has not been conclusively determined.

Based on a review of the literature the authors discuss the role of nutrition in the precipitation of migraine and tension-type headache (TTH). The available information relies largely on the subjective assessment of the patients. Controlled trials suggest that alcohol and caffeine withdrawal are the most important nutritional precipitating factors of migraine and TTH. In addition, there is some evidence that missing meals is also an important factor. Dehydration seems to deserve more attention. A selective sensitivity to red wine has been shown in some patients, the importance of chocolate has been doubted seriously, and scientific evidence for cheese as a precipitating factor is lacking. Despite a series of experimental studies demonstrating that NO donors such as nitroglycerin and parenteral histamine cause headache the role of histamine, nitrates, and nitrites in food remains unclear. Similarly, other biogenic amines and aspartame have not been proven to precipitate headache. Sodium glutamate causes adverse reactions including headache probably at large doses ingested on an empty stomach. Therefore, patients should be advised that food plays a limited role as a precipitating factor of migraine and TTH. Subjective sensitivity to certain foods should be examined critically, and proven precipitating factors should be avoided. General dietary restrictions have not been proven to be useful.

No abstract