Influence of serum vitamin D level on Helicobacter pylori eradication: A multi‐center, observational, prospective and cohort study

OBJECTIVES: This study was designed to test whether serum vitamin D levels affected Helicobacter pylori (H. pylori) infection and eradication rates. METHODS: A multicenter observational prospective cohort study was conducted. A total of 496 H. pylori (−) positive (H. pylori (+)) and 257 H. pylori‐negative (H. pylori (−)) patients were enrolled from four hospitals in China. Baseline serum vitamin D levels were measured and a (13)C‐urea breath test (UBT) was performed for all the participants. The H. pylori (+) patients were divided into two subgroups based on their serum vitamin D levels (<10 or ≥10 ng/mL). A second (13)C‐UBT was performed between 4 and 8 weeks after 14‐day bismuth‐containing quadruple eradication therapies. Factors potentially affecting H. pylori eradication were determined using a questionnaire survey. RESULTS: Serum vitamin D levels were significantly lower in the H. pylori (+) group than in the H. pylori (−) group ([17.0 ± 6.9] ng/mL vs [19.2 ± 8.0] ng/mL, P = 0.000). H. pylori eradication rate significantly differed between patients with serum vitamin D levels of <10 ng/mL and ≥10 ng/mL (71.7% vs 87.3%, P = 0.005). A multivariate analysis showed that having serum vitamin D level ≥10 ng/mL was an independent risk factor for a successful H. pylori eradication (odds ratio 0.381, 95% confidence interval 0.183‐0.791, P = 0.010). CONCLUSIONS: Serum vitamin D level may affect H. pylori infection and its eradication. Randomized controlled trials are needed to find out whether vitamin D supplements may increase the H. pylori eradication rate.