title: Association between Helicobacter pylori infection and migraine: a meta-analysis.
abstract: OBJECTIVE
  To quantify the association between Helicobacter pylori (H. pylori) infection and migraine.
  
  
  METHODS
  A systematic literature search of PubMed and EMBASE was conducted from inception to December 2013. Studies that provided data dealing with H. pylori infection in patients with migraine, as well as healthy controls, were selected. Meta-analysis was carried out using the odds ratio (OR) with a fixed or random effects model, and a 95%CI for the OR was calculated. An unconditional logistic regression model was used to analyze potential parameters related to H. pylori prevalence. Subgroup analyses were conducted as methods of detection and evidence grade.
  
  
  RESULTS
  Five case-control studies published between 2000 and 2013 were finally identified, involving 903 patients, with a total H. pylori infection rate of 39.31%. The prevalence of H. pylori infection was significantly greater in migraineurs than in controls (44.97% vs 33.26%, OR = 1.92, 95%CI: 1.05-3.51, P = 0.001). A sensitivity test indicated that no single study dominated the combined results. Univariate regression analysis found that publication year, geographical distribution and evidence grade were relevant to the results and were the main reason for the heterogeneity. Subgroup analysis found a significantly greater infection rate of H. pylori in Asian patients with migraine, but no statistically significant infection rate in European patients. The ORs were 3.48 (95%CI: 2.09-5.81, P = 0.000) and 1.19 (95%CI: 0.86-1.65, P = 0.288), respectively.
  
  
  CONCLUSIONS
  The pooled data suggest a trend of more frequent H. pylori infections in patients with migraine.
authors.affiliation: Jing Su, Xiao-Ying Zhou, Guo-Xin Zhang, Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Su
authors.affiliation: Jing Su, Xiao-Ying Zhou, Guo-Xin Zhang, Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Zhou
authors.affiliation: Jing Su, Xiao-Ying Zhou, Guo-Xin Zhang, Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
authors.forename: Guo-Xin
authors.initials: GX
authors.lastname: Zhang
mesh_terms: D044466:Asian People; D016481:Helicobacter Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D016015:Logistic Models; D008881:Migraine Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D016017:Odds Ratio; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D044465:White People
keywords: Helicobacter pylori; Meta-analysis; Migraine; Odds ratio; Subgroup analysis