Effect of curing Helicobacter pylori infection on intragastric pH during treatment with omeprazole

Vonoprazan poses no additional risk of developing Clostridioides difficile infection compared to proton pump inhibitors

BACKGROUND AND AIM

The use of proton pump inhibitors (PPIs) has been repeatedly reported as a trigger of Clostridioides difficile infection (CDI), a leading cause of nosocomial diarrhea. However, only a few studies have reported on the association between vonoprazan, a novel potassium-competitive acid blocker providing potent acid suppression, and CDI, with no studies having been conducted in a clinical setting. We therefore evaluated the association between various classes of acid suppressants and CDI with special attention paid to differences in the magnitudes of association between PPIs and vonoprazan.

METHODS

A retrospective hospital-based cohort from a secondary-care hospital in Japan (n = 25 821) was collected, wherein eligible CDI cases were defined as hospital-onset cases (n = 91). A multivariable adjusted logistic regression analysis for the entire cohort and propensity analyses for subgroups consisting of PPI and/or vonoprazan users at various doses (n = 10 306) were performed.

RESULTS

The overall CDI incidence rate was 1.42/10 000 patient-days, which was comparable with previous reports. A multivariable analysis showed that both PPIs and vonoprazan were positively associated with CDI (odds ratios [95% confidence intervals]: 3.15 [1.67-5.96] and 2.63 [1.01-6.88], respectively). In addition, matched subgroup analyses showed that PPIs and vonoprazan had equivalent magnitudes of association with CDI.

CONCLUSIONS

We found that both PPIs and vonoprazan were associated with CDI, and the magnitude of the association was comparable. Because vonoprazan is widely available in Asian countries, further studies on the association of its usage with CDI are warranted.

Effect of acid-reducing agents on clinical relapse in ulcerative colitis with pH-dependent-released 5-aminosalicylic acid: a multicenter retrospective study in Japan

BACKGROUND/AIMS

5-Aminosalicylic acid (5-ASA) is a basic drug for inducing and maintaining remission for ulcerative colitis. One of its formulations has a coating with a pH-dependent degradation that ensures the release 5-ASA at the terminal ileum. No evidence has been shown concerning the effects of proton pump inhibitors (PPIs) or H2 receptor antagonists (H2RAs) on the clinical course of ulcerative colitis patients in remission. The present study assessed the effect of PPIs or H2RAs on the relapse of ulcerative colitis patients in clinical remission maintained by pH-dependent released 5-ASA.

METHODS

Ulcerative colitis patients who had been prescribed time- or pH-dependent-released 5-ASA between January 2015 and December 2018 were enrolled in this multicenter retrospective study. The period of remission until relapse occurred was analyzed among the patients taking time-dependent-released 5-ASA or pH-dependent-released 5-ASA with/without PPIs or H2RAs.

RESULTS

One hundred and nineteen patients were analyzed in this study. In the primary endpoint, the relapse rate was higher in patients taking pH-dependent-released 5-ASA and PPIs or H2RAs than in those taking the pH-dependent-released 5-ASA without PPIs or H2RAs, while the relapse rate was similar in patients taking the time-dependent-released 5-ASA with or without PPIs or H2RAs concomitantly. Patients with a short duration of disease and middle-aged patients more frequently showed relapse with PPIs or H2RAs than the other patients.

CONCLUSIONS

The coadministration of PPIs or H2RAs affects the clinical course of ulcerative colitis in remission maintained by pH-dependent-released 5-ASA.

Are Patients with Perforated Peptic Ulcers Who are Negative for Helicobacter pylori at a Greater Risk?

Background: The link between Helicobacter pylori infection and peptic ulceration is well established. Recent studies have reported a decrease of H. pylori-related peptic ulcer disease; Helicobacter pylori eradication is likely the cause of this decrease. We hypothesized that patients with H. pylori-positive perforated peptic ulcer disease (PPUD) requiring surgical intervention had worse outcomes than patients with H. pylori-negative PPUD. Patients and Methods: A prospectively collected Acute and Critical Care Surgery registry spanning the years 2008 to 2015 was searched for patients with PPUD and tested for H. pylori serum immunoglobulin G (IgG) test. Patients were divided into two cohorts: H. pylori positive (HPP) and H. pylori negative (HPN). Demographics, laboratory values, medication history, social history, and esophagogastroduodenoscopy were collected. Student t-test was used for continuous variables and χ² test was used for categorical variables. Linear regression was applied as appropriate. Results: We identified 107 patients diagnosed with PPUD, of whom 79 (74%) patients had H. pylori serum IgG testing. Forty-two (53.2%) tested positive and 37 (46.8%) tested negative. Helicobacter pylori-negative PPUD was more frequent in females (70.27%, p = 0.004), whites (83.78%, p = 0.001) and patients with higher body mass index (BMI) 28.81 ± 8.8 (p = 0.033). The HPN group had a lower serum albumin level (2.97 ± 0.96 vs. 3.86 ± 0.91 p = 0.0001), higher American Society of Anesthesiologists (ASA; 3.11 ± 0.85 vs. 2.60 ± 0.73; p = 0.005), and Charlson comorbidity index (4.81 ± 2.74 vs. 2.98 ± 2.71; p = 0.004). On unadjusted analysis the HPN cohort had a longer hospital length of stay (LOS; 20.20 ± 13.82 vs. 8.48 ± 7.24; p = 0.0001), intensive care unit (ICU) LOS (10.97 ± 11.60 vs. 1.95 ± 4.59; p = 0.0001), increased ventilator days (4.54 ± 6.74 vs. 0.98 ± 2.85; p = 0.004), and higher rates of 30-day re-admission (11; 29.73% vs. 5; 11.91%; p = 0.049). Regression models showed that HPN PPUD patients had longer hospital and ICU LOS by 11 days (p = 0.002) and 8 days (p = 0.002), respectively, compared with HPP PPUD. Conclusion: In contrast to our hypothesis, HPN patients had clinically worse outcomes than HPP patients. These findings may represent a difference in the baseline pathophysiology of the peptic ulcer disease process. Further investigation is warranted.

All disease begins in the gut: Influence of gastrointestinal disorders and surgery on oral drug performance

The term "disease" conjures a plethora of graphic imagery for many, and the use of drugs to combat symptoms and treat underlying pathology is at the core of modern medicine. However, the effects of the various gastrointestinal diseases, infections, co-morbidities and the impact of gastrointestinal surgery on the pharmacokinetic and pharmacodynamic behaviour of drugs have been largely overlooked. The better elucidation of disease pathology and the role of underlying cellular and molecular mechanisms have increased our knowledge as far as diagnoses and prognoses are concerned. In addition, the recent advances in our understanding of the intestinal microbiome have linked the composition and function of gut microbiota to disease predisposition and development. This knowledge, however, applies less so in the context of drug absorption and distribution for orally administered dosage forms. Here, we revisit and re-evaluate the influence of a portfolio of gastrointestinal diseases and surgical effects on the functionality of the gastrointestinal tract, their implications for drug delivery and attempt to uncover significant links for clinical practice.

Proton pump inhibitors for functional dyspepsia

BACKGROUND

Functional dyspepsia (FD or non-ulcer dyspepsia) is defined as continuous or frequently recurring epigastric pain or discomfort for which no organic cause can be found. Acid suppressive therapy, including proton pump inhibitors (PPIs), has been proposed as a therapeutic option in FD, but its efficacy remains controversial. While PPIs are generally considered safe and well tolerated, they have been associated with adverse events, especially in the long term. For this reason, decisions on whether to initiate or continue PPI therapy should be made based on an appropriate clinical indication. Therefore, we conducted a systematic review to evaluate whether PPI therapy provides symptomatic relief in FD.

OBJECTIVES

To determine the efficacy of proton pump inhibitors in the improvement of global symptoms of dyspepsia and quality of life compared to placebo, H2 receptor antagonists or prokinetics, in people with functional dyspepsia.

SEARCH METHODS

We searched in the following electronic databases: the Cochrane Library (to May 2017), MEDLINE (OvidSP; to May 2017), Embase (OvidSP; to May 2017), and SIGLE grey literature (up to May 2017) and clinical trial registries; we handsearched abstracts from conferences up to May 2017. We screened non-systematic reviews, systematic reviews and guidelines to identify any additional trials. We contacted trialists to obtain missing information.

SELECTION CRITERIA

All randomized controlled trials (RCTs) comparing any PPI with placebo, H2 receptor antagonists (H2RAs) or prokinetics for the treatment of FD of at least two weeks' duration. Participants were adults (aged 16 years or greater) with an adequate diagnosis of FD (any validated criteria such as Rome I, II, III or Lancet Working Group).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility and trial quality, and extracted data. We collected data on dyspeptic symptoms, quality of life and number of overall adverse events. Specific adverse events were beyond the scope of this review.

MAIN RESULTS

We identified 25 RCTs from 27 papers (with 8453 participants) studying the effect of PPIs versus placebo, H2RAs or prokinetics for improvement of global symptoms of dyspepsia and quality of life in people with FD. Low-dose PPIs had similar efficacy as standard-dose PPIs, therefore we combined these subgroups for the analysis. PPI was more effective than placebo at relieving overall dyspepsia symptoms in people with FD (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.82 to 0.94; participants = 6172; studies = 18; number needed to treat for an additional beneficial outcome (NNTB) 11; moderate quality evidence). PPIs may have little or no effect compared with H2RAs (RR 0.88, 95% CI 0.74 to 1.04; participants = 740; studies = 2; low quality evidence), and may be slightly more effective than prokinetics (RR 0.89, 95% CI 0.81 to 0.99; participants = 1033; studies = 5; NNTB 16; low quality evidence) at relieving overall dyspepsia symptoms in people with FD. PPIs plus prokinetics have probably little or no effect compared with PPIs alone at relieving overall dyspepsia symptoms (RR 0.85, 95% CI 0.68 to 1.08; participants = 407; studies = 2; moderate quality evidence).There was no difference when subgrouped by Helicobacter pylori status, country of origin, or presence of reflux or Rome III subtypes. There were no differences in the number of adverse events observed between PPIs and any of the other treatments. There were fewer adverse events in the combination of PPI plus prokinetics compared to prokinetics alone (RR 0.60, 95% CI 0.39 to 0.93; participants = 407; studies = 2; moderate quality evidence).

AUTHORS' CONCLUSIONS

There is evidence that PPIs are effective for the treatment of FD, independent of the dose and duration of treatment compared with placebo. PPIs may be slightly more effective than prokinetics for the treatment of FD; however, the evidence is scarce. The trials evaluating PPIs versus prokinetics are difficult to interpret as they are at risk of bias. Although the effect of these drugs seems to be small, the drugs are well tolerated.

Helicobacter pylori-Induced Changes in Gastric Acid Secretion and Upper Gastrointestinal Disease

Appropriate management of Helicobacter pylori infection of the human stomach is evolving and remains a significant clinical challenge. Acute infection results in hypochlorhydria, whereas chronic infection results in either hypo- or hyperchlorhydria, depending upon the anatomic site of infection. Acute hypochlorhydria facilitates survival of the bacterium and its infection of the stomach. Interestingly, most patients chronically infected with H. pylori manifest a pangastritis with reduced acid secretion due to bacterial virulence factors, inflammatory cytokines, and various degrees of gastric atrophy. While these patients are predisposed to develop gastric adenocarcinoma (~1%), there is increasing evidence from population studies that they are also protected from gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Eradication of H. pylori, in these patients, may provoke GERD in predisposed individuals and may be a contributory factor for the rising incidence of refractory GERD, BE, and EAC observed in Westernized societies. Only ~10% of chronically infected patients, mainly the young, manifest an antral predominant gastritis with increased acid secretion due to a decrease in somatostatin and increase in gastrin secretion; these patients are predisposed to develop peptic ulcer disease. H. pylori-induced changes in acid secretion, in particular hypochlorhydria, may allow ingested microorganisms to survive transit through the stomach and colonize the distal intestine and colon. Such perturbation of gut microbiota, i.e. dysbiosis, may influence human health and disease.

Proton pump inhibitors for functional dyspepsia

BACKGROUND

Functional dyspepsia (FD or non-ulcer dyspepsia) is defined as continuous or frequently recurring epigastric pain or discomfort for which no organic cause can be found. Acid suppressive therapy, including proton pump inhibitors (PPIs), has been proposed as a therapeutic option in FD, but its efficacy remains controversial. While PPIs are generally considered safe and well tolerated, they have been associated with adverse events, especially in the long term. For this reason, decisions on whether to initiate or continue PPI therapy should be made based on an appropriate clinical indication. Therefore, we conducted a systematic review to evaluate whether PPI therapy provides symptomatic relief in FD.

OBJECTIVES

To determine the efficacy of proton pump inhibitors in the improvement of global symptoms of dyspepsia and quality of life compared to placebo, H2 receptor antagonists or prokinetics, in people with functional dyspepsia.

SEARCH METHODS

We searched in the following electronic databases: the Cochrane Library (to January 2016), MEDLINE (OvidSP; to February 2016), Embase (OvidSP; to February 2016), and SIGLE grey literature (up to February 2016) and clinical trial registries; we handsearched abstracts from conferences up to February 2016. We screened non-systematic reviews, systematic reviews and guidelines to identify any additional trials. We contacted trialists to obtain missing information.

SELECTION CRITERIA

All randomized controlled trials (RCTs) comparing any PPI with placebo, H2 receptor antagonists (H2RAs) or prokinetics for the treatment of FD. Participants were adults (aged 16 years or greater) with an adequate diagnosis of FD (any validated criteria such as Rome I, II, III or Lancet Working Group).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility, trial quality and extracted data. We collected data on dyspeptic symptoms, quality of life and number of overall adverse events. Specific adverse events were beyond the scope of this review.

MAIN RESULTS

We identified 23 RCTs from 22 papers (with 8759 participants) studying the effect of PPIs versus placebo, H2RAs or prokinetics for improvement of global symptoms of dyspepsia and quality of life in people with FD. Low-dose PPIs had similar efficacy as standard-dose PPIs, therefore we combined these subgroups for the analysis. Two to eight weeks of therapy with PPI was slightly more effective than placebo at relieving overall dyspepsia symptoms in people with FD (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.82 to 0.94; participants = 5968; studies = 16; number needed to treat for an additional beneficial outcome (NNTB) 13; moderate quality evidence). PPIs may be slightly more effective than H2RAs (RR 0.88, 95% CI 0.74 to 1.04; participants = 740; studies = 2, NNTB 13; low quality evidence), and slightly more effective than prokinetics (RR 0.90, 95% CI 0.81 to 1.00; participants = 892; studies = 4; NNTB 20; low quality evidence) at relieving overall dyspepsia symptoms in people with FD. PPIs plus prokinetics were possibly slightly more effective than PPIs alone at relieving overall dyspepsia symptoms (RR 0.85, 95% CI 0.68 to 1.08; participants = 407; studies = 2; NNTB 18; moderate quality evidence).The was no difference when subgrouped by Helicobacter pylori status, country of origin, or presence of reflux or Rome III subtypes. There were no differences in the number of adverse events observed between PPIs and any of the other treatments.

AUTHORS' CONCLUSIONS

There is evidence that PPIs are effective for the treatment of FD, independent of the dose and duration of treatment compared with placebo. PPIs may be slightly more effective than H2RAs for the treatment of FD; however, the evidence is scarce. The trials evaluating PPIs versus prokinetics are difficult to interpret as they are at risk of bias. Although the effect of these drugs seems to be small, the drugs are well tolerated.

Helicobacter pylori-negative and non-steroidal anti-inflammatory drugs-negative idiopathic peptic ulcers show refractoriness and high recurrence incidence: Multicenter follow-up study of peptic ulcers in Japan

BACKGROUND AND AIM

Helicobacter pylori-negative and non-steroidal anti-inflammatory drugs (NSAIDs)-negative idiopathic peptic ulcers (IPU) have attracted attention in Japan and other developed countries. The aim of the present study was to clarify the healing rate of IPU and the risk of recurrence.

METHODS

We conducted a retrospective follow-up study of patients with peptic ulcer disease (PUD) who were diagnosed in our previous multicenter-prospective study. Three hundred and eighty-two patients from four institutions in the Tohoku district were enrolled. Enrolled subjects were divided into four groups according to H. pylori infection and intake of NSAIDs. In these patients, we checked treatment course, healing rate during 3 months, and recurrence rate.

RESULTS

Healing rates in the: (i) simple H. pylori group; (ii) H. pylori (+)/ NSAIDs (+) group, (iii) simple NSAIDs group; and (iv) IPU group, were 95.0%, 94.9%, 73.3%, and 77.4%, respectively. The healing rate of the IPU group was significantly lower than that of both the simple H. pylori group and the H. pylori (+)/ NSAIDs (+) group (P < 0.01). The recurrence rate of 13.9% in the IPU group was much higher than the 2.1% in the simple H. pylori group (P < 0.01). Additionally, the cumulative recurrence rates by the Kaplan-Meier method in the IPU group were significantly higher than those of the simple H. pylori group (P = 0.015).

CONCLUSION

We demonstrated that the clinical course of peptic ulcers is considerably different depending on the cause. IPU could be refractory to treatment and prone to recur compared with simple H. pylori ulcers.

Proton pump inhibitors and risk of periampullary cancers--A nested case-control study

Considerable attention has been focused on long-term use of proton pump inhibitor (PPI) medications in relation to increased risk of cancer via stimulation of DNA-damaged cells. The aim of this study is to examine the dose-dependent effect of PPI on periampullary cancers in a national population-based cohort. A nested case-control analysis was constructed based on Taiwan's National Health Insurance Research Database and the Taiwan Cancer Registry between the years 2000 and 2010. Cases involving patients diagnosed with periampullary cancers were selected and controls were matched to cases according to age, sex and observational period. A "PPI user" was defined as any patient receiving more than 28 cumulative defined daily doses as measured by prescription drug claims. Conditional logistic regression analysis was conducted to calculate odds ratios (ORs) and 95% confidence intervals (CIs) according to the level of PPI exposure. A total of 7,681 cases and 76,762 matched controls were included with a mean follow-up period of 6.6 years (SD: 2.0). The odds of PPI exposure in patients with periampullary cancers were higher than that of control patients with an adjusted OR of 1.35 (95% CIs: 1.16-1.57). Our results also showed that PPI exposure was slightly linked to periampullary cancers in dose-dependent manner. A similar association was observed in patients who solely took PPI but no eradication therapy for Helicobacter pylori infection. Long-term PPI use was associated with an increased risk of periampullary cancers in the current population-based study. Physicians must weigh potential risks of long-term maintenance against therapeutic benefit.

The effect of orally administered ranitidine and once-daily or twice-daily orally administered omeprazole on intragastric pH in cats

BACKGROUND

Gastric acid suppressants frequently are used in cats with acid-related gastric disorders. However, it is not known if these drugs effectively increase intragastric pH in cats.

OBJECTIVES

To examine the effects of PO administered ranitidine and omeprazole on intragastric pH in cats and to compare the efficacy of once-daily versus twice-daily dosage regimens for omeprazole.

ANIMALS

Eight domestic shorthair cats.

METHODS

Using a randomized 4-way cross-over design, cats were given enteric-coated omeprazole granules (1.1-1.3 mg/kg q24h and q12h), ranitidine (1.5-2.3 mg/kg q12h), and placebo. Intragastric pH was monitored continuously for 96 hours using the Bravo(™) system, starting on day 4 of treatment, followed by a median washout period of 12 days. Mean percentage of time pH was ≥3 and ≥4 was compared among groups using repeated measures ANOVA.

RESULTS

Mean ± SD percentage of time intragastric pH was ≥3 and ≥4 was 67.0 ± 24.0% and 54.6 ± 26.4% for twice-daily omeprazole, 24.4 ± 22.8% and 16.8 ± 19.3% for once-daily omeprazole, 16.5 ± 9.0% and 9.6 ± 5.9% for ranitidine, and 9.4 ± 8.0% and 7.0 ± 6.6% for placebo administration. Twice-daily omeprazole treatment significantly increased intragastric pH, whereas pH after once-daily omeprazole and ranitidine treatments did not differ from that of placebo-treated cats.

CONCLUSION AND CLINICAL IMPORTANCE

Only twice-daily PO administered omeprazole significantly suppressed gastric acidity in healthy cats, whereas once-daily omeprazole and standard dosages of ranitidine were not effective acid suppressants in cats.

High Recurrence Rate of Idiopathic Peptic Ulcers in Long-Term Follow-up

Background/Aims

Our aim was to compare the long-term clinical outcomes of idiopathic peptic ulcer disease (IPUD) with those of Helicobacter pylori-positive and nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcer disease (PUD).

Methods

Patients with endoscopically diagnosed PUD were retrospectively reviewed. According to their H. pylori-infection status and history of NSAIDs use, patients were categorized into three groups: H. pylori-positive PUD, NSAID-induced PUD, and IPUD. Clinical outcomes were analyzed, and the recurrence rate of PUD was compared among the three groups.

Results

A total of 238 patients were enrolled. Those with IPUD, NSAID-induced PUD, and H. pylori-positive PUD comprised of 56, 60, and 122 patients, respectively. The 5-year cumulative incidences of recurrent ulcers were 24.3% (95% confidence interval [CI], 11.6% to 37.0%) in IPUD, 10.9% (95% CI, 2.6% to 19.2%) in NSAID-induced PUD, and 3.8% (95% CI, 0.1% to 7.5%) in H. pylori-positive PUD (IPUD vs NSAID-induced PUD/H. pylori-positive PUD, p=0.43/p<0.001 by log-rank test). In the Cox-proportional hazards model, only IPUD remained as an independent risk factor associated with recurrent ulcers (hazard ratio, 5.97; 95% CI, 1.94 to 18.34; p=0.002).

Conclusions

IPUD exhibited a higher recurrence rate than H. pylori-positive and NSAID-induced PUD in long-term follow-up and was an independent risk factor for ulcer recurrence.

Gastroesophageal reflux disease: an Asian perspective

The prevalence of gastroesophageal reflux disease (GERD) ranges from 2.5% to 7.1% in most population-based studies in Asia. There is evidence that GERD and its complications are rising, coinciding with a decline in Helicobacter pylori (H. pylori) infection. Asian GERD patients share similar risk factors and pathophysiological mechanisms with their Western counterparts. Possible causes for the lower prevalence of GERD include less obesity and hiatus hernia, a lesser degree of esophageal dysmotility, a high prevalence of virulent strains of H. pylori, and low awareness. Owing to the lack of precise translation for 'heartburn' in most Asian languages, reflux symptoms are often overlooked or misinterpreted as dyspepsia or chest pain. Furthermore, a symptom-based diagnosis with a therapeutic trial of the proton pump inhibitor (PPI) may be hampered by the high prevalence of H. pylori-related disease. The risk stratification for prompt endoscopy, use of a locally-validated, diagnostic symptom questionnaire, and response to H. pylori'test and treat' help improve the accuracy of the PPI test for diagnoses. PPI remain the gold standard treatment, and 'on-demand' PPI have been shown to be a cost-effective, long-term treatment. The clinical course of GERD is benign in most patients in Asia. The risk of progression from non-erosive reflux disease to erosive esophagitis is low, and treatment response to a conventional dose of PPI is generally higher. Although H. pylori eradication may lead to more resilient GERD in a subset of patients, the benefits of H. pylori eradication outweigh the risks, especially in Asian populations with a high incidence of gastric cancer.

Clinical trial design in adult reflux disease: a methodological workshop

BACKGROUND

The development of well-tolerated acid suppressant drugs has stimulated substantial growth in the number of trials assessing therapy options for gastro-oesophageal reflux disease (GERD).

AIM

To develop consensus statements to inform clinical trial design in adult patients with GERD.

METHODS

Draft statements were developed employing a systematic literature review. A modified Delphi process including three rounds of voting was used to reach consensus. Between voting, statements were revised based on feedback from the Working Group and additional literature reviews. The final vote was at a face-to-face meeting that included discussion time. Voting was conducted using a six-point scale.

RESULTS

At the last vote, 93% of the final 102 statements achieved consensus (defined a priori as being supported by >or=75% of the votes). The Working Group strongly supported the development of validated patient-reported outcome instruments. Symptom assessments carried out by the investigator were considered unacceptable. There was agreement that exclusion from clinical trials should be minimized to improve generalizability, that prospective evaluation ideally requires electronic timed/dated methods and that endoscopists should be blinded to patient symptom status.

CONCLUSIONS

Implementation of the consensus statements will improve the quality and comparability of trials, and make them compatible with regulatory requirements.

Gastric juice for the diagnosis of H pylori infection in patients on proton pump inhibitors

AIM: To determine the efficacy of gastric juice polymerase chain reaction (PCR) for the detection of H pylori infection in comparison with histology and gastric antral biopsy PCR in patients on a proton pump inhibitor (PPI).

METHODS: Eighty-five consecutive patients with dyspeptic symptoms were enrolled. Gastric biopsies for histology, PCR and gastric juice were collected at endoscopy for PCR of the H pylori urease C gene (ure C). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, positive and negative likelihood ratio for PCR of gastric juice for the H pylori ure C gene was compared to histology and gastric antral biopsy H pylori ure C PCR in patients with and without PPI.

RESULTS: Gastric juice PCR was positive in 66 (78%) patients. Histology showed H pylori associated gastritis in 57 (67%). Gastric biopsy PCR was positive in 72 (85%). In patients not taking PPI, the sensitivity, specificity, PPV, NPV, accuracy and positive and negative likelihood ratio for gastric juice PCR were 89%, 72%, 91%, 67%, 90%, 85%, 3.1 and 0.1 respectively. In patients on PPI these values were 86%, 100%%, 100%, 29%, 86%, 9.5 and 1.4, respectively.

CONCLUSION: Gastric juice PCR for the diagnosis of H pylori infection has increased sensitivity compared to histology with PPI. The use of gastric juice PCR is recommended to confirm H pylori status in patients taking PPIs.

The diagnostic yield of various tests for Helicobacter pylori infection in patients on acid-reducing drugs

The diagnostic yield of various tests for Helicobacter pylori infection in patients on acid-reducing drugs, such as proton pump inhibitors (PPI) and histamine-2 receptor blocker (H2RB), was compared. Seventy-four consecutive patients on acid-reducing drugs were enrolled: 34 (46%) were on PPIs, 20 (27%) were on H2RBs and 20 (27%) were not on medications. For those patients on PPIs, RUT and histology results from antrum were negative in 28 (82%) and 17 (50%) patients, respectively (OR: 4.7; 95% CI: 1.4-16.6; P = 0.004), while those from the corpus were negative in was 28 (82%) and 18 (53%) patients, respectively (OR: 4.4, 95% CI: 1.3-15.5; P = 0.006). For patients on H2RBs, RUT and histology results from the antrum were negative in 12 (60%) and six (30%) patients, respectively (OR: 3.5; 95% CI: 0.8-16.1; P = 0.05), while those from the corpus were negative in 12 (60%) and nine (45%) patients, respectively (OR: 1.8; 95% CI: 0.4-7.8; P = 0.342). For those patients on PPIs, the diagnostic yield of both RUT and histology was reduced from both the antrum and corpus. In these patients, PCR for H. pylori is more sensitive than RUT and histology.

Effect of intravenous application of esomeprazole 40 mg versus pantoprazole 40 mg on 24-hour intragastric pH in healthy adults

BACKGROUND

It has been demonstrated that therapy with proton pump inhibitors reduces recurrence of bleeding following initial endoscopic treatment of bleeding peptic ulcers.

AIM

This study compared the effects of esomeprazole 40 mg and pantoprazole 40 mg on intragastric acid control. Both substances were administered intravenously as 15-min infusion and as bolus injection.

METHODS

Healthy men and women volunteers were enrolled in this single-center, open, randomized, three-way crossover study. After administration of esomeprazole 40 mg and pantoprazole 40 mg intravenously as 15-min infusion, and pantoprazole 40 mg intravenously as bolus injection, continuous 24-h intragastric pH monitoring was carried out.

RESULTS

pH data were available for 21 Helicobacter pylori-negative and seven H. pylori-positive volunteers. In H. pylori-negative volunteers, esomeprazole 40 mg intravenously resulted in 11.8 h with an intragastric pH>4 compared with 5.6 h for pantoprazole 40 mg intravenously as infusion (P<0.0001), and 7.2 h for pantoprazole 40 mg intravenously as bolus injection (P<0.001). During the first 6 h of administration, the corresponding values were 3.4, 1.1 (P<0.000001), and 2.1 h (P<0.001), respectively.

CONCLUSIONS

In H. pylori-negative patients, a single dose of esomeprazole 40 mg intravenously provides an intragastric acid control that is faster and more pronounced than administration of pantoprazole 40 mg intravenously.

Acid-suppressive effects of rabeprazole: comparing 10mg and 20mg twice daily in Japanese Helicobacter pylori-negative and -positive CYP2C19 extensive metabolisers

BACKGROUND

Rabeprazole 10mg b.i.d. is often administered as therapy for eradication of Helicobacter pylori (H. pylori) and is also proposed as therapy for refractory gastro-oesophageal reflux disease. However, there has not been a comprehensive assessment of its acid-suppressive effects.

AIMS

To compare the acid-suppressive effects of rabeprazole 10mg b.i.d. with 20mg b.i.d. considering H. pylori status.

SUBJECTS

Thirteen H. pylori-negative and eleven H. pylori-positive Japanese CYP2C19 extensive metabolisers (<35 years).

METHODS

Intragastric pH was measured for 24h three times in a randomised manner; on day 7 of the repeated administration of rabeprazole 10mg b.i.d. or 20mg b.i.d., or a placebo.

RESULTS

In median intragastric pH value and percent time of pH>3.0, >4.0, >5.0, >6.0, and >7.0 for 24h, no significant differences were observed between the two doses in either H. pylori-negative or H. pylori-positive subjects. At either dose, these parameters were significantly higher in H. pylori-positive subjects than in H. pylori-negative subjects. Nocturnal acid breakthrough occurred in seven and two of the thirteen H. pylori-negative subjects and one and two of the eleven H. pylori-positive subjects at each dose, respectively.

CONCLUSIONS

The effects of rabeprazole 10mg b.i.d. were equal to those of 20mg b.i.d. in H. pylori-positive subjects; whereas in H. pylori-negative subjects, 20mg b.i.d. was superior for prevention of nocturnal acid breakthrough.

Does Helicobacter pylori infection influence response rate or speed of symptom control in patients with gastroesophageal reflux disease treated with rabeprazole?

OBJECTIVE

The findings of several studies suggest that proton-pump inhibitors (PPIs) suppress gastric acid more effectively in Helicobacter pylori-infected (Hp +) than in non-infected (Hp -) patients, but there has been no evaluation of the short-term clinical response.

MATERIAL AND METHODS

Results of the first week of treatment with rabeprazole in Hp+ and Hp- patients with gastroesophageal reflux disease (GERD) were compared in a large prospective open-label, multicenter, cohort study in general and specialized practices. GERD patients were recruited on the basis of either typical symptoms alone or endoscopic results, assessed for H. pylori infection and treated with rabeprazole (20 mg). Heartburn and regurgitation symptoms were assessed daily during the first 7 days. Outcome parameters were calculated for both symptoms and compared between Hp+ and Hp- patients.

RESULTS

Data on 1548 patients (74.5% Hp-, 25.5% Hp + ) were available. Mean heartburn and regurgitation scores decreased during the first week. For both symptoms, more than 70% of the patients had "adequate" symptom relief at day 5, and more than 80% at day 7. "Complete" symptom relief was reached in more than 70% of patients. Mean onset of adequate symptom control was about 4 days. In Hp+ and Hp- patients there was no difference in response for any of the parameters.

CONCLUSIONS

Among patients treated with rabeprazole in clinical practice, H. pylori infection or its absence has no effect on the speed or degree of GERD symptom relief. Infected patients and non-infected patients can therefore be treated with a similar dose. When treating heartburn with rabeprazole, physicians do not need to consider the patient's H. pylori status and most patients (>80%) have adequate symptom relief after just a few days of treatment.

Consequences of long-term proton pump blockade: insights from studies of patients with gastrinomas

Proton pump inhibitors are being increasingly used and for longer periods of time, especially in patients with gastroesophageal reflux disease. Each of these trends has led to numerous studies and reviews of the potential risk-benefit ratio of the long-term use of proton pump inhibitors. Both long-term effects of hypergastrinaemia due to the profound acid suppression caused by proton pump inhibitors as well as the effects of hypo-/achlorhydria per se have been raised and studied. Potential areas of concern that have been raised in the long-term use of proton pump inhibitors, which could alter this risk-benefit ratio include: gastric carcinoid formation; the development of rebound acid hypersecretion when proton pump inhibitor treatment is stopped; the development of tolerance; increased oxyntic gastritis in H. pylori patients and the possibility of increasing the risk of gastric cancer; the possible stimulation of growth of non-gastric tumours due to hypergastrinaemia; and the possible effect of the hypo/achlorhydria on nutrient absorption, particularly iron and vitamin B12. Because few patients with idiopathic gastro-oesophageal reflux disease/peptic ulcer disease have been treated long-term (i.e., >10 years), there is little known to address the above areas of potential concern. Most patients with gastrinomas with Zollinger-Ellison syndrome have life-long hypergastrinaemia, require continuous proton pump inhibitors treatment and a number of studies report results of >5-10 years of tratment and follow-up. Therefore, an analysis of Zollinger-Ellison syndrome patients can provide important insights into some of the safety concerns raised above. In this paper, results from studies of Zollinger-Ellison syndrome patients and other recent studies dealing with the safety concerns above, are briefly reviewed.

Validation of the blood quininium resin test for assessing gastric hypochlorhydria

Although gastric hypochlorhydria is a risk factor for gastroenteritis and for gastric cancer, no reliable, inexpensive, noninvasive test exists for screening or epidemiologic studies. We aimed to evaluate the sensitivity and specificity of the blood quininium resin test (bQRT) for hypochlorhydria, against pH monitoring. Twelve fasting adult volunteers-seven with and five without H. pylori infection-ingested 80 mg/kg of quininium resin twice, once with and once without acid suppression. Gastric pH was monitored for 75 minutes; serum samples were obtained at times 0 and 75 minutes. The bQRT levels were compared to gastric pH, controlling for omeprazole use and H. pylori infection. Subjects with a median recorded pH > or =3.5 were considered hypochlorhydric. Using a bQRT level of 10 as a cutoff for hypochlorhydria, the sensitivity and specificity of the bQRT were 100% and 37.5%, respectively. The bQRT predicted omeprazole use more accurately than pH monitoring. In conclusions, The bQRT has a high sensitivity for hypochlorhydria, making it potentially useful in populations with a high prevalence of hypochlorhydria. In its current formulation, the bQRT's low specificity makes it less useful in low-risk population.

Cost-effectiveness of Helicobacter pylori "test and treat" for patients with typical reflux symptoms in a population with a high prevalence of H. pylori infection: a Markov model analysis

OBJECTIVE

Patients with typical reflux symptoms may have underlying peptic ulcer disease (PUD) in a population with a high prevalence of Helicobacter pylori infection. In the present study we sought to compare the cost-effectiveness of the H. pylori "test and treat" strategy with that of empirical proton-pump inhibitor (PPI) therapy and endoscopy in patients with typical reflux and a high prevalence of H. pylori infection.

MATERIAL AND METHODS

A Markov model was designed to compare the outcomes of three treatment strategies over 12 months among a hypothetical cohort of patients presenting with typical reflux symptoms. There were four exclusive underlying H. pylori- and PUD-related comorbidities in the hypothetical cohort: (1) H. pylori-related PUD, (2) H. pylori infection without PUD, (3) PUD without H. pylori infection and (4) absence of both PUD and H. pylori infection. The transition probabilities and resource utilization were derived from the literature. Percentage of PUD patients treated, total number of symptom-free patient-years gained and total direct medical cost were estimated.

RESULTS

By comparing each strategy individually with the no therapy strategy, it was found that the incremental costs per ulcer treated for H. pylori "test and treat", endoscopy and empirical PPI therapy were USD 1778, USD 1797 and USD 2158, respectively. The results of the model were sensitive to the prevalence of H. pylori infection.

CONCLUSIONS

Both the H. pylori "test and treat" and initial endoscopic strategies were shown to be more cost-effective than empirical PPI therapy for treating undiagnosed PUD among patients presenting with typical reflux symptoms. The H. pylori "test and treat" strategy appeared to be only slightly more cost-effective than initial endoscopy in a population with a high prevalence of H. pylori infection.

Impact of Helicobacter pylori eradication on the anti-secretory efficacy of lansoprazole in gastroesophageal reflux disease patients

BACKGROUND

Helicobacter pylori eradication was recommended for the prevention of atrophic gastritis in gastroesophageal reflux disease (GERD) patients on long-term omeprazole treatment. It has been also shown that the treatment with proton pump inhibitors produces lower intragastric pH after H. pylori eradication in subjects with peptic ulcer and healthy individuals. The aim of the present study was to test the hypothesis of whether the efficacy of lansoprazole is reduced after the eradication of H. pylori in GERD patients with peptic esophagitis.

METHODS

Eight-hour intragastric pH recordings were performed before and after an 8-day course of lansoprazole (30 mg once daily) in 10 H. pylori-positive male patients with reflux esophagitis and were repeated after the H. pylori eradication. Intragastric acidity was measured by using an antimony electrode placed 10 cm below the cardia.

RESULTS

Baseline median preprandial, post-prandial, total intragastric pH and the percentage of time with pH < 3 were not different before and after H. pylori eradication without lansoprazole treatment. During lansoprazole treatment, median post-prandial intragastric pH was lower (4 vs 2.7; P < 0.05) and the percentage of time with pH < 3 was longer (3.4%vs 41.8%; P < 0.05) after H. pylori eradication. Median total intragastric pH tended to be lower after eradication but no difference was found in preprandial median pH.

CONCLUSIONS

In patients with reflux esophagitis treated with lansoprazole, intragastric pH increased significantly when H. pylori was present, especially in the post-prandial period, whereas baseline pH remained unchanged after H. pylori eradication.

The incidence of reflux oesophagitis after eradication therapy for Helicobacter pylori

BACKGROUND

Although several studies have indicated that Helicobacter pylori eradication develops reflux oesophagitis, others reported that its eradication had a beneficial effect on reflux symptoms. The results are still controversial.

OBJECTIVE

To study whether H. pylori eradication increases the occurrence rate of reflux oesophagitis in patients with peptic ulcers.

METHOD

One hundred and two consecutive patients who had peptic ulcers and were H. pylori-positive by C-urea breath testing were followed prospectively. They all received 1-week triple therapy and underwent endoscopy at 1-year intervals or when relapse of the peptic ulcer or occurrence of reflux oesophagitis was suspected.

RESULTS

Reflux oesophagitis developed in 32 (31.4%) out of 102 patients and they were of grade A (27 patients) and grade B (five patients) by the Los Angeles classification System. H. pylori infection was cured in 77 (75.5%) out of 102 patients. There was no significant difference in age (53.4+/-1.2 vs. 53.9+/-1.4 years, P = 0.43), gender (male/female, 29/3 vs. 53/17, P = 0.14), ulcer location (gastric/duodenal/both, 15/12/5 vs. 35/26/9, P = 0.97), H. pylori status (persistent/cured, 9/23 vs. 16/54, P = 0.57) or length of follow-up time (355+/-32 vs. 348+/-23 days, P = 0.30) between the 32 patients with reflux oesophagitis and the other 70 patients. Only the presence of hiatal hernia before therapy was significant for the prevalence of reflux oesophagitis by the log-rank test (P = 0.002), and the Cox proportional hazard models confirmed these findings (odds ratio, 3.46; 95% confidence interval, 1.64-7.30; P = 0.0012).

CONCLUSIONS

The eradication of H. pylori did not increase the prevalence of reflux oesophagitis, and only the presence of hiatal hernia before therapy was significantly related to the development of reflux oesophagitis.

Proton pump inhibitors reduce the bioavailability of dietary vitamin C

BACKGROUND

The gastric juice concentration of vitamin C is reduced in subjects with elevated intragastric pH. This is probably because of the fact that the vitamin is unstable at non-acidic pH and undergoes irreversible denaturation.

AIM

To determine whether elevation of intragastric pH reduces the bioavailability of dietary vitamin C.

METHODS

Plasma vitamin C was measured before and after a course of omeprazole 40 mg/day for 4 weeks in 14 Helicobacter pylori positive and 15 H. pylori negative subjects. Dietary intake of vitamin C was measured and intragastric pH monitored.

RESULTS

Compared with the H. pylori negative subjects, H. pylori positive subjects had a lower mean daily vitamin C intake (141.7 mg vs. 41.5 mg, P < 0.01) and also lower plasma vitamin C concentration (25.1 microg/mL vs. 17.4 microg/mL, P < 0.0001). After 28 days of 40 mg/day of omeprazole the mean plasma vitamin C level had fallen by 12.3% (P = 0.04). This fall affected both the H. pylori positive and negative subjects.

CONCLUSIONS

We have shown that a short course of omeprazole will cause a reduction in the plasma vitamin C level of healthy volunteers. This decrease in plasma vitamin C is independent of dietary intake of the vitamin and indicates reduced bioavailability. The clinical significance of this is unclear but any adverse effects will be most apparent in H. pylori infected subjects who have a low pre-treatment vitamin C status.

Long-term outcome of Helicobacter pylori-negative idiopathic bleeding ulcers: a prospective cohort study

BACKGROUND & AIMS

Helicobacter pylori-negative idiopathic ulcers are increasingly recognized. The secular trend and long-term outcome of this condition are unknown.

METHODS

We prospectively studied consecutive patients with bleeding gastroduodenal ulcers from January to December 2000. The incidence and etiology of ulcers during this period were compared with that between September 1997 and August 1998. H. pylori-negative idiopathic ulcers were defined as negative tests for H. pylori, no exposure to analgesics within 4 weeks, and absence of other risk factors for ulcers. After the ulcers had healed, patients with H. pylori-negative idiopathic ulcers and patients with H. pylori ulcers who received eradication therapy were followed up for 12 months without anti-ulcer drugs.

RESULTS

Six hundred thirty-eight patients had bleeding ulcers: 213 (33.4%) were H. pylori ulcers, and 120 (18.8%) were H. pylori-negative idiopathic ulcers (vs 480 [50.3%] H. pylori ulcers and 40 [4.2%] H. pylori-negative idiopathic ulcers in 1997-1998; P < .001). H. pylori-negative idiopathic ulcers accounted for 16.1% of patients who were admitted for bleeding and 42.4% of patients who bled while in the hospital (P < .0001); 28.3% of patients with H. pylori-negative idiopathic ulcers had histologic evidence of past H. pylori infection. The probability of recurrent ulcer complications in 12 months was 13.4% (95% CI: 7.3%-19.5%) in patients with H. pylori-negative idiopathic ulcers and 2.5% (95% CI: 0.4%-4.6%) in patients with H. pylori ulcers who received eradication therapy (P = .0002).

CONCLUSIONS

The incidence of H. pylori-negative idiopathic bleeding ulcers is rising. These ulcers are prone to recurrent complications.

Indicaciones y consecuencias de la erradicación de Helicobacter pylori en la enfermedad por reflujo gastroesofágico

Several epidemiological data indicate that H. pylori infection prevalence in patients with gastroesophageal reflux disease (GERD) is lower than that reported in respective controls, which would suggest that the organism plays a protective role against this disease. On the other hand, most studies demonstrate that the presence of the infection in patients with GERD does not negatively affect the therapeutic efficacy of proton pump inhibitors (PPIs), and, in case of negatively influencing it, the effects are not clinically relevant and are easily controllable with standard antisecretory treatment. Therefore, the decision to administer H. pylori eradication treatment to a patient should not be influenced by the concomitant presence of GERD. In most cases, H. pylori eradication does not seem to induce GERD development, and it does not seem to worsen GERD when it was already present. Nevertheless, when the gastritis pattern is unknown before the antibiotic administration, the effect of H. pylori eradication on gastric acid secretion and the incidence of GERD is unpredictable. In the exceptional cases in which H. pylori eradication could have negative effects on GERD, its clinical relevance will be limited, and reflux symptoms or endoscopic esophagitis will favourably respond to the standard PPI antisecretory treatment. Therefore, again, when H. pylori eradication is indicated in a particular patient, the concomitant diagnosis of GERD should not change our attitude. Finally, is has recently been recommended to eradicate H. pylori infection in those patients with GERD needing long-term treatment with PPI, as some studies have reported that these drugs induce, in presence of the organism, an atrophic gastritis, with the consequent risk of gastric cancer. However, most of these studies have important methodological defects, and several authors have reported contrary results. In any case, the appearance in the gastric mucosa of clinically relevant lesions, such as intestinal metaplasia, dysplasia or adenocarcinoma, in patients treated with PPI for several years, has not yet been demonstrated, although this could simply be a problem of time. This question seems to be too controversial to be answered with the available data, and we should wait until new studies clarify this topic. In the meantime, as it occurs with any controversial indication, the decision of the doctor facing a patient infected by H. pylori and needing maintenance therapy with PPIs should be assessed on a case by case basis.

Pantoprazole in severe acid-peptic disease: the effectiveness and safety of 5 years' continuous treatment

OBJECTIVE

This is our final report on the clinical effectiveness and safety of long-term pantoprazole in patients with severe peptic ulcer or reflux disease during continuous treatment for up to 5 years.

METHODS

Patients (n= 150) with peptic ulcer or reflux erosive oesophagitis running an aggressive course or with complications, and refractory to H2-receptor antagonists, were entered into this 5-year programme. Assessment was by serial endoscopy, clinical examination, serum gastrin estimation, gastric mucosal histology and mucosal endocrine cell quantification.

RESULTS

Healing results were presented earlier. The estimated rates of remission on maintenance treatment with pantoprazole (n = 115) were 82% at 1 year, 75% at 2 years, 72% at 3 years, 70% at 4 years and 68% at 5 years. Helicobacter pylori infection appeared not to influence the outcome in reflux patients, with roughly two-thirds continuing in remission irrespective of infection. Only four patients had adverse events considered to be definitely related to pantoprazole. Median gastrin levels rose by 1.5-2-fold and were higher in those with H. pylori infection; 13 patients had levels >500 ng/L on at least one occasion, but these high levels were not sustained. Histological changes were more marked in patients infected with H. pylori: chronic gastritis decreased in the antrum and increased in the corpus, which also showed atrophic changes. The total number of endocrine cells in the antrum showed little variation over 60 months but fell by around one-third in the corpus.

CONCLUSION

Long-term treatment with pantoprazole is effective and safe.

Review article: gastric pH -- the most relevant predictor of benefit in reflux disease?

Summary In patients with gastro-oesophageal reflux disease, the pH of refluxed gastric contents has a direct bearing on disease severity and oesophageal damage. A pH of 4 has been defined as a threshold below which refluxed gastric contents become injurious to the oesophagus. Studies in patients with erosive oesophagitis have shown that the 8-week healing rates produced by acid suppressive therapy are related to the duration of time over a 24-h period that the intragastric pH > 4. The most effective agents, providing more hours with gastric pH > 4 and higher healing rates in erosive oesophagitis patients, are the proton pump inhibitors. The intragastric pH is often used to gauge the efficacy of acid suppressive therapies. There are several factors, however, that may affect the clinical relevance of such data, and these should be taken into account when comparing the effectiveness of different therapies. Firstly, because of inter-individual variation, studies comparing therapies should be of a crossover design, so that responses to therapy are measured in the same individuals. Secondly, the Helicobacter pylori status of the individual should be known, as H. pylori infection has been shown to increase intragastric pH readings when examining the effect of acid suppressive therapy. Other factors, such as positioning of the pH electrode and the duration of previous therapy, also need to be standardized when using intragastric pH to assess the efficacy of different therapies. Crossover studies comparing standard doses of different proton pump inhibitors have shown that esomeprazole 40 mg produces a significantly greater amount of time at intragastric pH > 4 on day 5 of treatment than standard doses of other proton pump inhibitors. The correlation between greater efficacy in acid suppression and clinical benefit is supported by the findings that esomeprazole 40 mg is the only proton pump inhibitor to provide greater 8-week healing rates in patients with erosive oesophagitis than both omeprazole and lansoprazole. These data all suggest strongly that intragastric pH monitoring is an effective surrogate marker and a relevant predictor of outcome in gastro-oesophageal reflux disease.

Impact de l’infection à Helicobacter pylori sur le risque de complications gastro-duodénales des traitements anti-inflammatoires non stéroïdiens

The interaction of Helicobacter pylori (H. pylori) and non steroidal anti-inflammatory drugs (NSAIDs) on the development of gastro-duodenal ulcers and their complications is complex and controversial. From a clinical point of view, the question is whether or not H. pylori infection should be tested and eradicated in patients treated or about to be treated by NSAIDs or low-dose aspirin. Contradictory results have been reported in epidemiological studies. Recent data suggest that H. pylori-NSAID interaction may be different depending on the type of treatment, non aspirin NSAIDs or low-dose aspirin, the gastric or duodenal localization of ulcer and the strains of H. pylori. Controlled randomized studies suggest that eradication of H. pylori may be beneficial in NSAID-naïve patients but not in those already on long term NSAID therapy. Recommendations are proposed for different subgroups of patients. In NSAID users presenting with gastro-duodenal ulcer or complications, H. pylori screening and eradication are indicated. In patients treated or about to be treated by NSAIDs, the "test and treat" H. pylori strategy is recommended if there is a history of gastroduodenal ulcer or complications. Whether this strategy should be generalized preventively in patients without ulcer history is still controversial and deserves further studies.

Traitements curatif et préventif des ulcères gastro-duodénaux induits par les AINS

The use of treatments to heal or to prevent nonsteroidal anti-inflammatory drugs (NSAIDs) associated gastroduodenal lesions is based on replacement of mucosal prostaglandin deficiency or inhibition of acid secretion. Four-week acid suppression by proton pump inhibitors (PPI) with 7-day eradication triple therapy in Helicobacter pylori positive patients is effective in healing gastric and duodenal ulcer upon discontinuation of NSAIDs. In the event NSAIDs must be continued, PPIs (omeprazole 20 mg, lansoprazole 30 mg, pantoprazole 40 mg) are more effective than H2-blockers and cytoprotective agents (sucralfate, misoprostol) to heal mucosal lesions. In long-term prevention studies, omeprazole 20 mg, lansoprazole 15 mg, and pantoprazole 20 mg significantly reduce gastric and duodenal ulcer rates. Misoprostol 800 microg is as effective as PPIs for preventing symptomatic and complicated gastric ulcers, but less effective to prevent duodenal ulcer, with a high rate of adverse effects such as diarrhea. Helicobacter pylori eradication in infected patients decrease the risk of NSAIDs-associated lesions but is less effective than concomitant antisecretory treatment. Current data from comparative studies of PPIs vs ranitidine or misoprostol are in favor of the PPIs as well tolerated and effective drugs in the prophylaxis of NSAIDs-related gastroduodenal lesions in high-risk patients.

Helicobacter pylori eradication does not exacerbate gastro-oesophageal reflux disease

The reciprocal influence of Helicobacter pylori infection and gastro-oesophageal reflux disease (GORD), if both conditions occur concomitantly, has been an issue of debate for many years. The critical question is whether eradication of H pylori has a more beneficial, harmful, or simply no effect on the course of GORD.

Effect of Helicobacter pylori eradication on treatment of gastro-oesophageal reflux disease: a double blind, placebo controlled, randomised trial

BACKGROUND

The role of Helicobacter pylori eradication in the management of gastro-oesophageal reflux disease (GORD) is controversial. We hypothesised that H pylori eradication leads to worsened control of reflux disease.

METHODS

Consecutive patients with weekly reflux symptoms were prospectively recruited for endoscopy and symptom evaluation. Patients were enrolled if they had H pylori infection and required long term acid suppressants. Eligible patients were randomly assigned to omeprazole triple therapy (HpE group) or omeprazole with placebo antibiotics (Hp+ group) for one week. Omeprazole 20 mg daily was given for eight weeks for healing of oesophagitis and symptom relief. This was followed by a maintenance dose of 10 mg daily for up to 12 months. The primary study end point was the probability of treatment failure within 12 months, which was defined as either incomplete resolution of symptoms or oesophagitis at the initial treatment phase, or relapse of symptoms and oesophagitis during the maintenance phase. Predictors of treatment failure were determined by Cox's proportional hazards model.

RESULTS

A total of 236 GORD patients were screened and 113 (47.9%) were positive for H pylori; 104 (92%) patients were included in the intention to treat analysis (53 in the HpE group and 51 in the Hp+ group). Thirty one patients (30%) had erosive oesophagitis at baseline. H pylori was eradicated in 98% of the HpE group and in 3.9% of the Hp+ group. Overall, 15 patients (28.3%) in the HpE group and eight patients (15.7%) in the Hp+ group had treatment failure. The 12 month probability of treatment failure was 43.2% (95% confidence interval (CI) 29.9-56.5%) in the HpE group and 21.1% (95% CI 9.9-32.3%) in the Hp+ group (log rank test, p = 0.043). In the Cox proportional hazards model, after adjustment for the covariates age, sex, erosive oesophagitis, hiatus hernia, degree of gastritis, and severity of symptoms at baseline, H pylori eradication was the only predictor of treatment failure (adjusted hazard ratio 2.47 (95% CI 1.05-5.85)).

CONCLUSION

H pylori eradication leads to more resilient GORD.

Inhibitory potency of twice-a-day omeprazole on gastric acidity is enhanced by eradication of H. pylori in duodenal ulcer patients

The gastric pH-elevating effect of proton pump inhibitors such as omeprazole has been reported to be greater in the presence than in the absence of an H. pylori infection. It is unknown if this effect persists when a higher dose of omeprazole is taken. We undertook both 24-hr pH-metry and 24-hr aspiration studies in 12 H. pylori-positive patients with a history of duodenal ulcer (DU); (1) when not on omeprazole; (2) when on omeprazole 20 mg twice a day for 8 days; (3) two months after eradication of H. pylori and when not on omeprazole; and (4) after eradication of H. pylori and when on omeprazole twice a day. Eradication of H. pylori in DU results in lower mean and median pH; decreased percent pH > or = 3/ > or = 4, and greater median H+ after breakfast, after lunch, and overnight; and omeprazole appears to have less of a pH-elevating effect in the absence than in the presence of an H. pylori infection. The fall in gastric juice NH3 concentration as a result of eradicating H. pylori partially explained the lower pH-elevating effect of omeprazole. The variation in acid inhibitory effect of omeprazole after as compared with before eradication of H. pylori could not be explained by differences; (1) in gastric juice concentrations of IL-1alpha, IL-8, IL-13, or epidermal growth factor; (2) in the fasting or fed total concentration of gastric juice bile acids; (3) in the fasting concentrations or area under-the-curve (AUC) of the gastric H+ concentrations in response to food; or (4) in the pharmacokinetics of omeprazole. The difference in H+ AUC without omeprazole minus with omeprazole was actually greater when compared after versus before eradication of H. pylori. Thus, in DU the pH-elevating potency of omeprazole taken twice a day is greater in the presence than in the absence of an H. pylori infection.

Comparison of the effect on intragastric pH of a single dose of omeprazole or rabeprazole: which is suitable for on-demand therapy?

BACKGROUND AND AIMS

An ideal medication for heartburn should have the rapid onset of action needed for on-demand treatment. However, assessment of the onset of action of proton pump inhibitors has been largely subjective. We compared the inhibitory effect on gastric acid secretion of a single oral dose of omeprazole with that of rabeprazole.

METHODS

Fourteen Helicobacter pylori-negative men participated in this randomized, double-masked, two-way cross-over study. Intragastric pH was monitored continuously for 6 h after a single, randomly assigned 20 mg oral dose of either omeprazole or rabeprazole. After a 7-day washout period, the other drug was administered. Each patient's S-mephenytoin 4'-hydroxylase (CYP2C19) genotype was determined by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Intragastric pH and pH holding time did not differ between treatments when the data were analyzed for the whole group without stratifying for CYP2C19 status. In CYP2C19 homozygous and heterozygous extensive metabolizers (10 subjects), rabeprazole maintained the intragastric at pH > 3 and> 4 for longer than omeprazole during both the 5 and 6 h study periods, and the average pH during the 6 h study period was higher with rabeprazole than with omeprazole. In these extensive metabolizers, rabeprazole maintained the pH > 2,> 3,> 3.5 and> 4 for longer during the 6 h study period than did omeprazole.

CONCLUSIONS

In H. pylori-negative men who are CYP2C19 homozygous or heterozygous extensive metabolizers, the intragastric pH after a single dose of 20 mg rabeprazole is higher during first 5-6 h than that after a single dose of 20 mg omeprazole.

The changing epidemiology of GERD: geography and Helicobacter pylori

BACKGROUND

Issues have arisen regarding H. pylori infection and GERD that have caused unnecessary confusion among practicing physicians. In the last century GERD became increasingly recognized in the West and it has become evident that the prevalence of GERD is now occurring in many previously underdeveloped countries.

METHODS

This review article fosters understanding of the issues by focusing on the esophageal acid load and the factors that control it. In particular, we discuss the effects of the change in the patterns of gastritis that have occurred naturally as well as after H. pylori eradication and correlate those changes with their effects on the esophageal acid load. We show how it is possible to separate gastroesophageal reflux from gastroesophageal reflux disease based on differences in esophageal acid load. We also describe how the practice of assessing gastroesophageal reflux based on the time the intraesophageal pH is less than 4 resulted in investigators systematically discarding data critical to understanding of the effect of their interventions on esophageal acid load. Testable hypotheses are presented to explain the interactions between H. pylori and GERD and between H. pylori and the changing epidemiology of GERD.

CONCLUSIONS

We propose that the confusion regarding H. pylori and the changing epidemiology of GERD is based on the failure to critically examine the historical evidence in relation to the other H. pylori-related diseases as well as reliance on techniques that are either unable to measure, or systematically discard data critical for understanding effects of various interventions on the esophageal acid load. This has resulted in propagation of erroneous concepts regarding H. pylori and adenocarcinoma of the esophagus and has resulted in some patients being denied appropriate therapy.

Eradication of Helicobacter pylori increases nocturnal intragastric acidity during dosing with rabeprazole, omeprazole, lansoprazole and placebo

BACKGROUND

The eradication of Helicobacter pylori decreases the antisecretory activity of omeprazole and lansoprazole. Rabeprazole is a potent proton pump inhibitor that may not be affected as greatly by H. pylori status.

AIM

To compare the effect of H. pylori eradication on intragastric acidity and plasma gastrin during dosing with lansoprazole, omeprazole, rabeprazole and placebo.

METHODS

Twenty-four healthy H. pylori-infected volunteers were studied on day 7 of dosing with placebo, lansoprazole 30 mg, omeprazole 20 mg and rabeprazole 20 mg, before and at least 5 weeks after H. pylori eradication. On each occasion, the 24-h intragastric acidity was measured by gastric aspiration. Plasma gastrin concentrations were measured hourly from 08.00 to 13.00 h.

RESULTS

Sixteen subjects completed the study. For all three drugs and placebo, H. pylori eradication increased intragastric acidity, particularly nocturnal acidity, and decreased plasma gastrin. There were no differences between the three drugs with respect to 24-h acidity, percentage of time pH > 4 or 5-h plasma gastrin, either before or after H. pylori eradication. Before eradication, the percentage nocturnal time at pH > 3 was significantly greater during rabeprazole than during lanso-prazole dosing.

CONCLUSIONS

The increase in intragastric acidity seen after H. pylori eradication during dosing with proton pump inhibitors is a drug-class effect, particularly affecting nocturnal acid control. This is related to increased spontaneous intragastric acidity after H. pylori eradication.

Acid inhibitory potency of twice a day omeprazole is not affected by eradication of Helicobacter pylori in healthy volunteers

BACKGROUND AND AIMS

The acid inhibitory effect of proton pump inhibitors is reported to be greater in the presence than in the absence of an H. pylori infection. This study was undertaken to test the hypothesis that the acid inhibitory effect of omeprazole given twice a day is greater in H. pylori infected healthy volunteers than in the same individuals following eradication because of differences in the pharmacodynamics of omeprazole, greater duodenogastric reflux, the effects of ammonia produced by the H. pylori, or lower gastric juice concentrations of selected cytokines, which may inhibit gastric acid secretion.

MATERIALS AND METHODS

We undertook 24-hour pH-metry in 12 H. pylori-positive healthy volunteers: (1) when on no omeprazole; (2) when on omeprazole 20 mg bid for 8 days; (3) 2 months after eradication of H. pylori and when on no omeprazole; and (4) after eradication of H. pylori and when on omeprazole 20 mg twice a day.

RESULTS

In subjects given omeprazole, eradication of H. pylori reduced pH and percentage pH >or= 3, as well as increasing the area under the H+ concentration-time curve. These differences were not due to alterations in (1) gastric juice concentrations of IL-1alpha, IL-8, IL-13, epidermal growth factor, or bile acids; (2) serum gastrin concentrations; or (3) the pharmacokinetics of omeprazole. There was no change in the difference in the H+ concentration-time curve 'without omeprazole' minus 'with omeprazole', when comparing 'after' versus 'before' eradication of H. pylori.

CONCLUSIONS

Eradication of H. pylori was not associated with an alteration in the acid inhibitory potency when comparing the difference in gastric acidity 'with' versus 'without' omeprazole. When the results were expressed by simply taking into account the acid measurements while on omeprazole before versus after eradication of H. pylori, the acid inhibition with omeprazole was greater in the presence than in the absence of a H. pylori infection. The clinical significance of the small difference is not clear.

Effects of rabeprazole, lansoprazole and omeprazole on intragastric pH in CYP2C19 extensive metabolizers

AIM

To investigate the inhibitory effects on gastric acid secretion of three proton pump inhibitors, omeprazole, lansoprazole and rabeprazole, using a three-way crossover design in healthy Helicobacter pylori-negative,S-mephenytoin 4'-hydroxylase (CYP2C19) homo- and hetero-extensive metabolizers.

METHODS

Eight healthy Japanese male volunteers were enrolled. After the administration of rabeprazole (10 mg/day), lansoprazole (30 mg/day) or omeprazole (20 mg/day), intragastric pH monitoring was commenced from 24 h before the first proton pump inhibitor dose, and continued for days 1-3 after proton pump inhibitor administration. The pH electrode was used for 48 h and changed just before pH monitoring on day 2.

RESULTS

For the administration of 10 mg/day rabeprazole, the mean ratios of the 24-h pH > or = 3 holding time were 5.7 +/- 1.1%,13.6 +/- 2.2%, 35.3 +/- 2.7% and 62.8 +/- 3.1% for the pre-treatment day and days 1, 2 and 3, respectively. The same ratios for lansoprazole (30 mg/day) were 5.7 +/- 0.7%, 7.4 +/- 1.5%, 13.6 +/- 3.4% and 26.6 +/- 4.9%; the same ratios for 20 mg/day omeprazole were 5.9 +/- 0.9%, 6.1 +/- 1.2%, 11.4 +/- 2.8% and 16.4 +/- 4.6%. The mean ratio of the 24-h pH > or = 3 holding time of days 1-3 increased significantly compared to the pre-treatment day (P < 0.01) with the administration of rabeprazole and lansoprazole. The magnitude of inhibition of gastric acid secretion after rabeprazole administration was stronger than that after lansoprazole. A significant elevation of the mean ratio of the 24-h pH > or = 3 holding time was demonstrated on days 2 and 3 with omeprazole (P < 0.01).

CONCLUSIONS

In H. pylori-negative CYP2C19 extensive metabolizers, rabeprazole (10 mg/day) shows a faster onset of rising intragastric pH and a stronger inhibition of gastric acid secretion than do lansoprazole (30 mg/day) or omeprazole (20 mg/day).

Helicobacter pylori-induced duodenal ulcer frequently coincides with gastro-oesophageal reflux disease

BACKGROUND

The relationship between Helicobacter pylori infection and gastro-oesophageal reflux disease is complicated. Evidence does not support a causal link. There have been reports, which have implicated successful eradication of Helicobacter pylori, in patients with a duodenal ulcer, with the subsequent development of gastro-oesophageal reflux disease. However, eradication of Helicobacter pylori in these patients with improvement in their condition and a return to normal lifestyle, weight gain and discontinuation of antacids may unmask pre-existing gastro-oesophageal reflux disease.

AIMS

To determine the true prevalence of gastro-oesophageal reflux disease in patients with Helicobacter pylori-related duodenal ulceration.

METHOD

Dyspeptic patients undergoing endoscopy were prospectively screened for the presence of a duodenal ulcer. Concomitant oesophagitis, when present, was recorded. All subjects with a Helicobacter pylori-related duodenal ulcer without endoscopic evidence of gastro-oesophageal reflux disease were invited to undergo a 24-hr ambulatory oesophageal pH assessment prior to receiving treatment.

RESULTS

A total of 97 patients with a duodenal ulcer were identified and 83.5% were Helicobacter pylori positive. Overall, 27.8% had associated endoscopic evidence of oesophagitis, 70% grade I-II and 30% grade III-IV. Of those without evidence of oesophagitis at endoscopy, 68% underwent a 24-hr pH assessment. An additional 17% were identified by this means as having gastro-oesophageal reflux disease. Overall, 44% of symptomatic subjects with Helicobacter pylori and a duodenal ulcer were found to have coexistent gastro-oesophageal reflux disease.

CONCLUSION

Gastro-oesophageal reflux disease is frequently found to coexist with Helicobacter pylori-related duodenal ulcer. In addition, almost 20% of symptomatic patients without endoscopic evidence of oesophagitis will have an abnormal oesophageal pH exposure. It is plausible that the development of gastro-oesophageal reflux disease following successful eradication of Helicobacter pylori represents unmasking of existing disease rather than de novo development.

Effect of Helicobacter pylori eradication on oesophageal acid exposure in patients with reflux oesophagitis

BACKGROUND

The effect of Helicobacter pylori eradication on reflux oesophagitis is unclear.

AIM

To study the effect of H. pylori eradication on oesophageal acid exposure and disease severity in patients with reflux oesophagitis.

METHODS

Patients with reflux oesophagitis and H. pylori infection were recruited for 24-h oesophageal pH-metry. They were then randomly assigned to receive either treatment for H. pylori eradication (1-week omeprazole-based triple therapy, followed by 7-week omeprazole) or omeprazole alone (8-week omeprazole). Uninfected patients were recruited as controls. Endoscopy, pH monitoring and symptom assessment were repeated at 26 weeks.

RESULTS

Forty patients (25 H. pylori-positive and 15 uninfected) with erosive oesophagitis were studied. Fourteen were randomized to receive treatment for H. pylori eradication and 11 to receive omeprazole alone. There was no difference in the percentage of time the oesophageal pH < 4 before and 26 weeks after treatment among the three groups. However, the percentage of time the oesophageal pH < 2 (P=0.01) and pH < 3 (P=0.02) was significantly increased in patients receiving treatment for H. pylori eradication. Three (21%) patients in the group receiving treatment for H. pylori eradication had worsening of reflux oesophagitis.

CONCLUSIONS

H. pylori eradication increases oesophageal acid exposure and may adversely affect the clinical course of reflux disease in a subset of patients.

Minor effects of Helicobacter pylori on gastric secretion and dose of lansoprazole during long-term treatment in ZE and non-ZE acid hypersecretors

BACKGROUND

Helicobacter pylori infection may increase or decrease acid secretion and may augment proton pump inhibitor efficacy. Pepsin effects have not been reported. In Zollinger-Ellison syndrome (ZE) specifically, H. pylori has been reported to decrease acid.

AIM

To examine H. pylori effects on secretion and dose of medication in hypersecretors (basal acid output > 15 mmol/h) undergoing long-term treatment with individually optimized lansoprazole doses.

METHODS

Sixty-five patients (47 ZE and 18 non-ZE), treated for > 3 months to 10 years, were tested every 6 months with endoscopy, gastric analysis and serum gastrin.

RESULTS

Forty-three per cent were H. pylori-positive. Acid, pepsin and gastrin were not different between H. pylori-positive and H. pylori-negative patients before or during long-term lansoprazole treatment. Initially, H. pylori-positive patients required less lansoprazole than H. pylori-negative patients (68 +/- 6 vs. 96 +/- 8 mg/day), but after 3 years the doses converged (83 vs. 86 mg/day). The disappearance of H. pylori in 15 patients caused no significant changes in acid, pepsin, gastrin or lansoprazole dose in the following 4 years.

CONCLUSIONS

H. pylori had no significant initial or long-term physiological or potential clinical effects on acid or pepsin secretion or gastrin in these acid hypersecretors.

Current indications for acid suppressants in dyspepsia

Anti-secretory drug use is common in patients with uninvestigated and functional dyspepsia, but the value of such agents has been controversial. Four large studies have evaluated the symptomatic outcome after a short course of acid inhibition in patients with uninvestigated dyspepsia presenting in primary care. All of these studies demonstrated a superior symptom response to proton pump inhibitor therapy compared with placebo and acid-alginates or H(2)-receptor antagonists. In patients with documented functional dyspepsia, 17 parallel group trials have evaluated an H(2)-receptor antagonist against placebo, with mixed results. A recent Cochrane review based on eight controlled trials concluded that there was a significant benefit of H(2)-blockers over placebo with a relative risk reduction of 30%, but as gastro-oesophageal reflux disease was not excluded, the conclusions are questionable. Six controlled studies have compared symptom relief after a short course of proton pump inhibitor therapy compared with placebo. Overall, there does appear to be a therapeutic gain with proton pump inhibitors over placebo, although how much of this is explained by undiagnosed gastro-oesophageal reflux disease remains unclear. There is conflicting evidence on the value of symptom subgrouping as a predictor of response to acid suppression. Overall, there is little convincing evidence that Helicobacter pylori infection influences the therapeutic outcome of acid-suppressant therapy. In conclusion, there appears to be a subgroup of patients with functional dyspepsia who will respond to acid suppression over and above placebo, but further work is required to characterize these responders.