Clopidogrel and proton pump inhibitors-where do we stand in 2012?

Clopidogrel in association with aspirine is considered state of the art of medical treatment for acute coronary syndrome by reducing the risk of new ischemic events.Concomitant treatment with proton pump inhibitors in order to prevent gastrointestinal side effects is recommended by clinical guidelines.Clopidogrel needs metabolic activation predominantly by the hepatic cytochrome P450 isoenzyme Cytochrome 2C19(CYP2C19) and proton pump inhibitors(PPIs) are extensively metabolized by the CYP2C19 isoenzyme as well.Several pharmacodynamic studies investigating a potential clopidogrel-PPI interaction found a significant decrease of the clopidogrel platelet antiaggregation effect for omeprazole,but not for pantoprazole.Initial clinical cohort studies in 2009 reported an increased risk for adverse cardiovascular events,when under clopidogrel and PPI treatment at the same time.These observations led the United States Food and Drug Administration and the European Medecines Agency to discourage the combination of clopidogrel and PPI(especially omeprazole) in the same year.In contrast,more recent retrospective cohort studies including propensity score matching and the only existing randomized trial have not shown any difference concerning adverse cardiovascular events when concomitantly on clopidogrel and PPI or only on clopidogrel.Three meta-analyses report an inverse correlation between clopidogrel-PPI interaction and study quality,with high and moderate quality studies not reporting any association,rising concern about unmeasured confounders biasing the low quality studies.Thus,no definite evidence exists for an effect on mortality.Because PPI induced risk reduction clearly overweighs the possible adverse cardiovascular risk in patients with high risk of gastrointestinal bleeding,combination of clopidogrel with the less CYP2C19 inhibiting pantoprazole should be recommended.

Correlation between Distribution of Helicobacter Pylori in Oral Cavity and Chronic Stomach Conditions

In this study,the colonization and distribution of Helicobacter pylori（Hp） in patients with chronic gastric diseases were investigated and the relationship between the periodontal initial treatment and presence of Hp in oral cavity was examined to better understand the connection between Hp infection and chronic diseases.Primers for PCR amplification were designed according to ureC gene and cagA genes of Hp.Specimens were harvested from different sites of 96 patients with chronic gastric diseases and the specimens of dental plaques,gargles and dorsal mucosa were tested for Hp.The 96 patients were treated by bismuth triple therapy and among them,52 subjects were additionally given periodontal initial therapy.The eradication rate of gastric Hp and oral Hp detection rate were determined 4 weeks and 1 year after the treatment.The results showed that the detection rates of oral specimens were in the order of dental plaques（82.3%）,gargles（51.1%） and scrapings of dorsal mucosa of tongue（37.5%）.One year after bismuth triple therapy or the triple therapy in combination with periodontal initial treatment,the eradication rate of gastric Hp was significantly higher in the combination treatment group than in group treated by the triple therapy alone（62.8% vs.32.4%,P0.05）.Moreover,the Hp detection rate was significantly lower in the combination group than in the group treated only with the triple therapy.We are led to conclude that Hp is present at various parts of oral cavity,oral Hp might be an important source of gastric Hp and the triple therapy plus periodontal initial treatment can enhance the long-term eradication rate of gastric Hp in patient with both chronic gastric diseases and chronic periodontitis.