Prevalence and associated risk factors of Helicobacter pylori infection in the Wuwei cohort of north-western China.

Objectives: To evaluate the prevalence of Helicobacter pylori infection and risk factors and to serotype the strains in Wuwei, located in north-western China, which has a high incidence of gastric cancer.

Methods: Helicobacter pylori infection was analysed in 21 291 adults by C-urea breath test, and H. pylori antibody were detected in 9183 serum samples by latex immunoturbidimetric method. The correlation of H. pylori infection with demographic-economic, lifestyle factors and medical history among the participants was determined by questionnaire. The antibodies against H. pylori urease, VacA and CagA in serum were determined by dot immunobinding assay.

Results: The infection rate of H. pylori was 53.0%, and 90.1% of strains were type I strains. The H. pylori infection rate was higher among farmers (OR = 1.34, 95% CI: 1.19-1.50) and individuals who had a junior high school or higher education level (OR = 1.10, 95% CI: 1.06-1.15), and was lower in older individuals (OR = 0.86, 95% CI: 0.83-0.90), individuals with high income (OR = 0.93, 95% CI: 0.90-0.95), individuals with a habit of eating quickly (OR = 0.93, 95% CI: 0.87-0.99) and individuals who consumed more fruit and vegetables (OR = 0.90, 95% CI: 0.85-0.95). Individuals with history of cholecystitis/cholecystolithiasis, hypertension and asthma were negatively correlated with H. pylori infection (P < 0.05).

Conclusion: The prevalence of H. pylori infection is high in Wuwei. The major prevalent strain is type I strain. Age, education, occupation, household income, consumption of fruit and vegetables, and habit of eating quickly are independent risk factors for H. pylori infection, which is also associated with individuals with a history of extragastric diseases.