Influence Of Serum Vitamin D Level On Helicobacter Pylori Eradication

ObjectiveThe aim of this study was to investigate whether serum vitamin D level affects Hp eradication.Methods1.To analyze the correlation between the related factors and the incidence of gastric cancer in the current years,we collected historical trend data of each related factor and figured out its Spearman rank correlation coefficient r using bivariate correlation statistical method.Then,we calculated the coefficient of determination R2 specific to the statistically significant factors and sorted it by the size of value.2.A multi-center observational cross-sectional study was performed.496 Hp positive and 257 Hp negative patients were enrolled from four centers.Serum vitamin D levels were detected for all patients.3.A multi-centre observational prospective cohort study was performed.Baseline serum levels of vitamin D and 13C-UBT were detected for all patients and a questionnaire survey was performed to explore the potential factors affecting Hp eradication.The Hp positive patients were divided into 2 groups based on serum levels of vitamin D <10 or ?10 ng/m L.A second 13C-UBT was performed to determine Hp eradication rates between 4 and 8 weeks after 14 days of treatment consisting of bismuth-containing quadruple eradication therapies for Hp-positive patients.A total of 415 Hp positive patients with eradication results were collected from the four centers after the exclusion of 81 patients lost of follow-up.Results1.The incidence of gastric cancer in rural areas had declined,while the incidence of gastric cancer in urban areas had been steadily stable and far below the level of rural areas.However,the incidence of gastric cancer in urban and rural areas was basically close since 2009 when urban incidence had risen slightly.The negatively related factors to the incidence of urban and rural gastric cancer are fresh fruits consumption,disposable income,the amount of refrigerators and aging level.The proportion of urban population is negatively related to urban gastric cancer incidence.The positively related factors to the incidence of rural gastric cancer are the consumption of high salt pickled food,the chemical oxygen demand emissions of industrial wastewater,the ammonia nitrogen emissions of industrial wastewater and the proportion of rural population.2.In our study,we found that serum vitamin D level was significantly lower in Hp positive group than that in Hp negative group(17.0±6.9 ng/ml vs 19.2±8.0 ng/ml,P<0.001).The other factors affecting vitamin D(such as age,gender,season and occupation)were not significantly different between the two groups.There was a negative correlation between serum vitamin D level and 13C-UBT.The serum vitamin D level of male was significantly higher than that of female.There was no correlation between age and vitamin D serum levels,and vitamin D serum levels were not significantly different between various gastric diseases.3.Significant differences were seen between the vitamin D serum levels <10 ng/ml group and ?10 ng/ml group in terms of the Hp eradication rate(71.7% vs 87.3%,P=0.005;Table 2).The factors affecting the eradication rate of Hp were analysed by using the questionnaire of 20 factors affecting Hp eradication.Univariate analysis showed that treatment with adequate dosage and duration,drinking alcohol and serum levels of vitamin D were significantly different between the Hp eradication success and failure groups.A multivariate analysis revealed that treatment without adequate dosage and duration(OR: 0.265,95% CI: 0.133-0.530,P<0.001)and vitamin D serum levels <10 ng/ml(OR: 0.381,95% CI: 0.183-0.791,P=0.010)were independent risk factors for Hp eradication failure.Conclusion1.In recent 30 years,the incidence of gastric cancer has been decreasing in China,which is mainly caused by the development of social economy and the change of life style.To further reduce the incidence of gastric cancer,the "detection and eradication" strategy of Helicobacter pylori(Hp)should be widely conducted.2.Serum vitamin D level may affect Hp infection.Low level of serum Vitamin D may potentiate Hp infection.3.Serum vitamin D level may affect the eradication of Hp.Hp-positive patients with severe serum vitamin D deficiency should be supplemented with vitamin D.Repeated eradication of patients with failed Hp should be tested for serum vitamin D levels when screening for causes..