title: Inverse association between Helicobacter pylori infection and allergic rhinitis in young Japanese.
abstract: OBJECTIVE
  The prevalence of allergic disorders, including asthma, atopic dermatitis, and allergic rhinitis has been increasing, and the prevalence of Helicobacter pylori (H. pylori) infection has been decreasing. Chronic bacterial infection during childhood is reported to protect the development of allergic diseases. The aim of the present study was to identify whether H. pylori infection influences the prevalence of allergic rhinitis, which has become a serious social problem, especially in the developed countries.
  
  
  METHODS
  We initially investigated the association between the prevalence of H. pylori and pollinosis symptoms in 97 healthy volunteers. We had investigated the association between the serum H. pylori-immunoglobulin (Ig) G antibodies and specific IgE antibodies for pollen, mites, and house dust in 211 consecutive patients.
  
  
  RESULTS
  There were 52.2% (36/69) of H. pylori-negative volunteers with allergic symptoms, which was significantly higher than H. pylori-positive volunteers (14.3%, 4/28, P < 0.05). The risk of pollinosis symptoms by H. pylori infection was 0.148 (95% confidence interval): 0.046-0.475, P < 0.05). The prevalence of H. pylori infection increased according to age, whereas that of specific IgE-positive patients gradually decreased. Among the IgE-positive patients, the prevalence of H. pylori-negative patients was significantly higher than H. pylori-positive patients who were younger in age (P < 0.05).
  
  
  CONCLUSIONS
  H. pylori infection decreased the pollinosis effects, especially among the younger volunteers. However, the prevalence of pollinosis in patients who were 50 years or older were almost same between H. pylori-positive and H. pylori-negative patients; therefore, the recent increase of pollinosis might relate to not only H. pylori infection, but also change in social environment.
authors.affiliation: Department of Internal Medicine, Aiseikai Yamashina Hospital, Kyoto, Japan.
authors.forename: Shigeyoshi
authors.initials: S
authors.lastname: Imamura
authors.forename: Mitsushige
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kanemasa
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Sumida
authors.forename: Takeshi
authors.initials: T
authors.lastname: Okanoue
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Yamaoka
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood; D039741:Antigens, Dermatophagoides / Q000276:immunology; D044466:Asian People; D016009:Chi-Square Distribution; D004391:Dust / Q000276:immunology; D005260:Female; D016481:Helicobacter Infections / Q000208:ethnology* / Q000276:immunology / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011058:Pollen / Q000276:immunology; D015995:Prevalence; D012221:Rhinitis, Allergic, Perennial / Q000208:ethnology* / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000208:ethnology* / Q000276:immunology; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D000907:Antibodies, Bacterial; D039741:Antigens, Dermatophagoides; D004391:Dust; D007074:Immunoglobulin G; D007073:Immunoglobulin E