SYSTEMATIC REVIEW CRITIQUE

Systematic Review Critique

Systematic Review Critique

Background

Helicobacter pylori (H pylori) is the major origin of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear.

Objectives

To assess whether H pylori eradication therapy improves individual or global dyspepsia symptom scores in patients with non-ulcer dyspepsia.

To assess whether H pylori eradication therapy alters quality of life scores in patients presenting with non-ulcer dyspepsia.

To assess whether H pylori eradication therapy improves the individual or global dyspepsia symptom scores in a subset of nonulcer dyspepsia patients defined by their predominant dyspepsia symptoms.

Search strategy

Trials were recognised through electrical devices searches of the Cochrane Controlled tests list (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, utilizing appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through associates with professionals in the areas of dyspepsia and with pharmaceutical companies.

Selection criteria

All parallel group randomized controlled tests (RCTs) comparing drugs to eradicate H pylori with placebo or other pharmaceuticals known not to eradicate H pylori for patients with non-ulcer dyspepsia.

Types of participants

Adult patients presenting to secondary care with H pylori and dyspepsia, who have negative or insignificant findings on their endoscopy or barium studies, and have had other organic (pancreatobiliary disease, oesophagitis, peptic ulcer disease and neo-plastic disease), drug-induced (non-steroidal anti-inflammatory drugs), and metabolic disorders excluded by appropriate investigations (such as blood tests, abdominal ultrasound or 24 hour oesophageal pH studies etc). Definitions of dyspepsia include any gastrointestinal symptoms referable to the foregut or any of those suggested in the Working Group (Working Party, 1988) and the Rome criteria (Talley, 1991). Trials where participants present with only heartburn or reflux symptoms (symptoms suggestive of gastro-oesophageal reflux disease) were not included.

Types of intervention

Trials comparing H pylori eradication regimens with placebo, or with other drugs known not to eradicate H pylori. The earlier literature used regimens that were ineffective in treating H pylori. We have therefore predefined acceptable H pylori eradication regimens, and only considered those trials which used recognised eradication therapies in a modern clinical setting. The following were considered acceptable regimens:

Dual therapy with proton pump inhibitor in combination with either clarithromycin or amoxycillin.

Triple therapy with either proton pump inhibitor or Histamine H2 receptor antagonists in combination with either (i) amoxycillin and nitroimidazole or (ii) amoxycillin and clarithromycin or (iii) clarithromycin and nitroimidazole.

Bismuth based triple therapy with metronidazole and either amoxycillin or tetracycline.

Quadruple therapy with proton pump inhibitor, bismuth, metronidazole, tetracycline or amoxycillin.

Data collection and analysis

Data were assembled on individual and international dyspeptic symptom scores, value of life measures and adverse effects. Dyspepsia conclusions were dichotomized into minimal/resolved versus same/worse symptoms.

Main results

Twenty one randomized controlled tests were encompassed in the systematic review. Eighteen trials contrasted anti-secretory dual or triple therapy with placebo antibiotics +/- anti-secretory treatment, and assessed dyspepsia at 3-12 months. Seventeen of these trials gave conclusions as dichotomous conclusions evaluating 3566 patients and there was no important heterogeneity between the studies. There was a 10% relation risk decrease in the H pylori eradication assembly (95% CI = 6% to 14%) compared to ...