title: Role of Helicobacter pylori and interleukin 6 -174 gene polymorphism in dyslipidemia: a case-control study.
abstract: OBJECTIVE
  To assess the role of Helicobacter pylori infection and interleukin 6 polymorphism -174 (rs1800795) in dyslipidemia.
  
  
  METHODS
  Case-control study comparing serum lipids between H. pylori positive and negative patients and controlling for IL-6 -174 polymorphism, age, sex and smoking.
  
  
  METHODS
  3 hospitals performing outpatient endoscopies in the city of Oulu, Finland.
  
  
  METHODS
  199 adult patients with dyspepsia symptoms fulfilling Rome criteria originating from ethnically Finnish population. Patients with an immunosuppressive disorder or malignant disease, treated H. pylori infection, immunosuppressive or anticoagulant medication, previous gastric surgery or ongoing antibiotic treatment were excluded.
  
  
  METHODS
  Association of H. pylori infection and serum lipid concentrations in the whole group or in genotype-based subgroups. The associations between peptic ulcer, gastric mucosal inflammation and serum lipid concentrations were assessed as secondary outcomes.
  
  
  RESULTS
  The median high-density lipoprotein (HDL) serum concentration was significantly lower in the H. pylori positive group (0.81 mmol/L) than in the negative group (0.95 mmol/L; p<0.001). In the genotype subgroup analyses, a similar association between H. pylori infection and HDL serum levels was seen within the IL-6 -174 CC genotype group (HDL 0.72 vs 1.06 mmol/L, respectively; p<0.001), but no significant associations were seen in the GC or GG genotype groups. Additionally, patients with peptic ulcer demonstrated lower HDL levels (0.75 mmol/L) than H. pylori positive patients without ulcer (0.86 mmol/L; p=0.010).
  
  
  CONCLUSIONS
  H. pylori infection associated significantly with low serum levels of HDL in the IL-6 -174 CC genotype patients but not in the other genotypes. This suggests that the association between H. pylori infection and serum HDL could be transmitted through IL-6. We suggest that the role of IL-6 genotype should also be studied in relation to other associations between gastrointestinal microbiome and cardiovascular risk factors.
authors.affiliation: Department of Pathology, Cancer and Translational Medicine Research Unit, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Vesa-Matti
authors.initials: VM
authors.lastname: Pohjanen
authors.affiliation: Department of Internal Medicine, Oulu University Hospital, Oulu, Finland.
authors.forename: Olli-Pekka
authors.initials: OP
authors.lastname: Koivurova
authors.affiliation: Department of Internal Medicine, Oulu University Hospital, Oulu, Finland.
authors.forename: Seppo E
authors.initials: SE
authors.lastname: Niemelä
authors.affiliation: Department of Medical Microbiology and Immunology, University of Oulu, Oulu, Finland.
authors.forename: Riitta A
authors.initials: RA
authors.lastname: Karttunen
authors.affiliation: Department of Pathology, Cancer and Translational Medicine Research Unit, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
authors.forename: Tuomo J
authors.initials: TJ
authors.lastname: Karttunen
mesh_terms: D016022:Case-Control Studies; D008076:Cholesterol, HDL / Q000097:blood; D050171:Dyslipidemias / Q000097:blood / Q000235:genetics* / Q000382:microbiology*; D005260:Female; D005387:Finland; D005756:Gastritis / Q000097:blood*; D005838:Genotype; D016481:Helicobacter Infections / Q000097:blood*; D016480:Helicobacter pylori; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic
chemical_list: D008076:Cholesterol, HDL; D015850:Interleukin-6
keywords: GENETICS; INFECTIOUS DISEASES