Relationship between Helicobacter pylori infection and bone mineral density: a retrospective cross-sectional study.

BACKGROUND: Helicobacter pylori (H. pylori) infection can induce individual inflammatory and immune reactions which associated with extra-digestive disorders. Our aim is to investigate the association between H. pylori infection and bone mineral density. METHODS: This retrospective cross-sectional study was performed by using the data from the health examination database in a medical center of southern Taiwan in 2013. We investigated the relationship between sex, age, body mass index (BMI), waist circumstance, lipid profile, H. pylori infection, the findings of upper gastrointestinal endoscopy and bone mineral density (BMD). Because of nonrandomized assignment and strong confounding effect of age on BMD, the 1:1 propensity score match was applied for age adjustment. The simple and multiple stepwise logistic regression analysis were performed to assess the risk factors of decreased BMD in these well-balanced pairs of participants. RESULTS: Of the 867 subjects in final analysis with the mean age of 55.9 ± 11.3 years, 381 (43.9%) subjects had H. pylori infection, and 556 (64.1%) subjects had decreased BMD. In decreased BMD group, the portion of woman was higher than a normal BMD group (37.2% versus 29.6%, P = 0.023), the age was significantly older (59.4 ± 9.8 versus 49.8 ± 11.3, p < 0.001) and BMI was significantly lower (24.7 ± 3.5 versus 25.4 ± 3.7, p = 0.006) than the normal BMD group. The prevalence of H. pylori infection was 39.9% and 46.2% in the normal BMD group and the decreased BMD group respectively (P = 0.071). The multivariate analysis which was used for these possible risk factors showed that only advanced age (OR 1.09, 95% CI 1.08-1.11, P < 0.001), and low BMI (OR 0.91, 95% CI 0.87-0.95, P < 0.001) were independently significantly associated with decreased BMD in this nonrandomized study. In the propensity score-matched participants, the multiple stepwise logistic regression analysis revealed H. pylori infection (OR 1.62, 95% CI 1.12-2.35, P = 0.011) and low BMI (OR 0.92, 95% CI 0.87-0.97, P = 0.001) were independently significantly associated with decreased BMD. CONCLUSIONS: H. pylori infection and low BMI were independently significantly associated with decreased BMD in selected propensity score-matched populations after age adjustment.