Reproducibility of a symptom response to omeprazole therapy in functional dyspepsia evaluated by a random-starting-day trial design

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.

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.

Therapeutic strategies for the treatment of dyspepsia

IMPORTANCE OF THE FIELD

Dyspeptic symptoms are highly prevalent in the population and represent a major burden for healthcare systems. The ROME III criteria address and define two separate entities of functional dyspepsia: epigastric pain syndrome and postprandial distress syndrome. The etiology of dyspeptic symptoms is heterogeneous, underlying mechanisms are poorly understood and symptomatic improvement after drug therapy is often incomplete.

AREAS COVERED IN THIS REVIEW

This review of the literature included Medline data being published in the field of functional dyspepsia and different therapies.

WHAT THE READER WILL GAIN

The reader will gain a current, unbiased understanding of the pathophysiological mechanisms underlying functional dyspepsia and of the therapeutic regimens based on randomized, controlled trials and on the meta-analyses that have been published on different therapeutic agents.

TAKE HOME MESSAGE

Before starting medical treatment, a careful physical examination should exclude 'alarm symptoms'. Laboratory data, ultrasound and endoscopy are recommended in patients older than 45 - 55 years (depending on the guidelines being used). In areas with a high prevalence of Helicobacter pylori, the initial strategy includes 'test and treat' for H. pylori in addition to empiric acid suppressive therapy. Many studies have focused on the role of gastrointestinal dysmotility and hypersensitivity for dyspepsia with inconclusive results. Further therapeutic medical strategies include prokinetics, herbal preparations and psycho-/neurotopic drugs as well as additional psycho- or hypnotherapy.

Symptomatic response to blocked and unblocked pentagastrin stimulation in functional dyspepsia. Comparison of responders and non-responders to omeprazole identified in a single-subject trial model

BACKGROUND

The role of acid in functional dyspepsia is controversial and drug treatment trials indicate that only a subset of patients has acid-related symptoms. A novel single-subject trial design, the Random Starting Day trial (RSD trial), was developed to identify acid-related symptoms. We hypothesized that RSD trial responders and non-responders would react differently to gastric acid stimulation. Development of epigastric pain was expected in RSD trial responders after pentagastrin stimulation during placebo treatment, but not during omeprazole treatment. In non-responders, epigastric pain was expected not to be influenced by gastric acid stimulation or type of treatment.

METHODS

Nineteen patients were evaluated. Symptomatic response to pentagastrin (6 microg/kg) was assessed twice in each patient following placebo and omeprazole (40 mg bid) treatment in a randomized, double-blind, cross-over design. Epigastric pain was assessed every 15 for 90 min after stimulation using a 5-graded Likert scale and a VAS scale. A positive acid provocation test was defined as an increase of the Likert score of epigastric pain by at least one grade after pentagastrin stimulation during placebo treatment but not during omeprazole treatment.

RESULTS

The acid provocation test was positive in 43% (3/7) of responders compared to only 17% (2/12) non-responders. VAS-score changes showed trends towards a more pronounced symptom reduction during omeprazole treatment in responders compared to non-responders.

CONCLUSION

Patients identified as having acid-related dyspepsia more often developed epigastric pain following acid stimulation during placebo and not during omeprazole treatment. Due to the low sample size the difference was not considered significant.

Effects of proton-pump inhibitors on functional dyspepsia: a meta-analysis of randomized placebo-controlled trials

BACKGROUND & AIMS

The aim of this study was to assess systematically the efficacy of proton pump inhibitors (PPIs) in the treatment of functional dyspepsia compared with placebo and to determine if any difference in the response exists between symptom subgroups of functional dyspepsia.

METHODS

A literature search was performed through September 2005 in PubMed, Medline, Embase, CINAHL, and Cochrane databases to include randomized, double-blind, placebo-controlled trials evaluating the efficacy of PPIs for the treatment of functional dyspepsia. Relative risk (RR) and relative risk reduction (RRR) and 95% confidence intervals (CI) were calculated under a random-effects model.

RESULTS

Seven studies with a total of 3725 patients were identified. PPIs were found to be more effective than placebo for reducing symptoms in patients with functional dyspepsia (RRR, 10.3%; 95% CI, 2.7%-17.3%). The estimated number needed to treat is 14.6 (95% CI, 8.7-57.1). When stratified analyses were performed, a significant difference in the efficacy was observed only in patients with ulcer-like (RRR, 12.8%; 95% CI, 7.2%-18.1%) and reflux-like dyspepsia (RRR, 19.7%; 95% CI, 1.8%-34.3%), but not in those with dysmotility-like (RRR, 5.1%; 95% CI, -10.9% to 18.7%) and unspecified dyspepsia (RRR, -8.0%; 95% CI, -23.7% to 5.6%). The effect of H pylori on the efficacy of PPIs remains unclear. Significant heterogeneity among studies was found for the overall analysis, dysmotility-like dyspepsia, H pylori-negative subgroup, and different dose subgroups.

CONCLUSIONS

PPIs are more effective than placebo for the management of patients with ulcer-like and reflux-like functional dyspepsia.

Drug treatment of functional dyspepsia

Symptomatic improvement of patients with functional dyspepsia after drug therapy is often incomplete and obtained in not more than 60% of patients. This is likely because functional dyspepsia is a heterogeneous disease. Although great advance has been achieved with the consensus definitions of the Rome I and II criteria, there are still some aspects about the definition of functional dyspepsia that require clarification. The Rome criteria explicitly recognise that epigastric pain or discomfort must be the predominant complaint in patients labelled as suffering from functional dyspepsia. However, this strict definition can create problems in the daily primary care clinical practice, where the patient with functional dyspepsia presents with multiple symptoms. Before starting drug therapy it is recommended to provide the patient with an explanation of the disease process and reassurance. A thorough physical examination and judicious use of laboratory data and endoscopy are also indicated. In general, the approach to treat patients with functional dyspepsia based on their main symptom is practical and effective. Generally, patients should be treated with acid suppressive therapy using proton-pump inhibitors if the predominant symptoms are epigastric pain or gastroesophageal reflux symptoms. Although the role of Helicobacter pylori (H pylori) in functional dyspepsia continues to be a matter of debate, recent data indicate that there is modest but clear benefit of eradication of H pylori in patients with functional dyspepsia. In addition, H pylori is a gastric carcinogen and if found it should be eliminated. Although there are no specific diets for patients with FD, it may be helpful to guide the patients on healthy exercise and eating habits.

Pathogenesis and therapy for idiopathic dyspepsia

Functional dyspepsia (FD) is one of the most common gastrointestinal disorders. This review summarizes recent progress in our understanding of the pathogenesis and therapy for FD. Although distinction among FD, irritable bowel syndrome, and reflux disease is difficult in population-based studies, separate entities can be recognized in patients who seek medical attention. The pathogenesis of FD remains unclear, but recent studies have demonstrated a role for acute gastrointestinal infection in triggering FD and in genetic polymorphisms of G-proteins in predisposing to FD. The role of abnormalities in gastric motor function, visceral hypersensitivity, and psychosocial factors in the pathophysiology of dyspeptic symptoms has been the topic of multiple studies. Treatment options for FD remain limited. Recent studies have focused on acid-suppressive drugs and on novel prokinetics. Progress in our understanding of the pathogenesis and pathophysiology of FD may lead to new or improved treatment modalities. Areas of major advances are the role of infection and genetic predisposition and studies on the role of abnormalities in gastric motility and sensitivity.