Helicobacter pylori infection as an environmental risk factor for migraine without aura

Helicobacter pylori (H. pylori) infection has recently been associated with various extraintestinal pathologies and migraine. The aim of this study was to investigate the correlation of the H. pylori infection with the pathogenesis of migraine without aura, especially in cases not affected by endogenous risk factors, like hereditary pattern or hormonal fluctuations.A total of 49 outpatients (37 females and 12 males; age range: 19-47 years; mean age: 31,+/-14 years) affected by migraine without aura was evaluated. We divided them in 2 subgroups: a) with positive familial history, and/or with menstrual type of migraine b) with negative familial history and with menstrual unrelated type of migraine. H. pylori infection was diagnosed by the 13 C- urea breath test (INFAI - test). Control subjects consisted of 51 patients without any primary headache history (38 females; mean age of 32,+/-14,4 years; range 21-49 years), who underwent upper gastrointestinal (GI) endoscopy for investigation of anaemia or non ulcer dyspepsia. H. pylori detection was based on the histologic analysis of gastric mucosa biopsy. The prevalence of H. pylori infection was significantly higher in the migraineurs without aura compared to controls (p=0.016). The prevalence of H. pylori infection was significantly high in the mixed and in the female group of our patients without other predisposing factors for migraine without aura (81 and 87% respectively), while in the same groups with predisposing factors (menstruation and/or family history) the prevalence was only 36 and 37% respectively (p=0,001 for the first group and p=0,002 for the second group). Our results seem to highlight the role of H. pylori infection as a probable independent environmental risk factor for migraine without aura, especially in patients that are not genetically or hormonally susceptible to migraine.