Interictal burden of headache: results from the Eurolight study

Abstract

Background: Most estimates of the heavy disability burden attributed to headache derive from epidemiological data focused on episodic migraine and tension-type headache (TTH). These disorders give rise directly, but intermittently, to symptom burden, but People with them may not be entirely symptom-free between attacks. We analysed the Eurolight dataset for interictal burden. Methods: Eurolight was a cross-sectional survey using modified cluster sampling from the adult population (18–65 years) in 10 countries of the European Union. We used data from nine. The questionnaire included headache- diagnostic questions based on ICHD-II and several question sets addressing impact, including interictal and cumulative burdens. Results: There were 6,455 participants (male 2,444 [37.9%]) with headache. Interictal symptoms were reported by 26.0% of those with migraine and 18.9% with TTH: interictal anxiety by 10.6% with migraine, avoidance (lifestyle compromise) by 14.8%, both much more common than in TTH (3.1% [OR 3.8] and 4.7% [OR 3.5] respectively). Mean time spent in the interictal state was 317 days/year for migraine, 331 days/year for TTH. Those who were ‘‘rarely’’ or ‘‘never’’ in control of their headaches (migraine 15.2%, TTH 9.6%) had significantly raised odds of interictal anxiety, avoidance and other interictal symptoms. Among those with migraine, interictal anxiety increased markedly with headache intensity and frequency, avoidance less so but still significantly. Lost productive time was associated with high odds (OR up to 5.3) of anxiety and avoidance. Discussion: Interictal burden in those with episodic headache is common, more so in migraine than TTH. Some elements have the potential to be profoundly consequential.