Should patients with nonulcer dyspepsia and Helicobacter pylori be treated with antibiotics?

BACKGROUND: Dyspepsia (defined as pain or discomfort centered in the upper abdomen) is a common primary care problem, but optimal management is unclear. Nonulcer dyspepsia is the most common subtype, and controversy exists regarding the role of H pylori in this subtype. This systematic review assesses the efficacy of treatment for H pylori on symptoms of dyspepsia.

POPULATION STUDIED: The authors combined the results of 10 studies of therapy of 1747 patients with nonulcer dyspepsia and documented H pylori infection. The investigators included only randomized controlled trials lasting at least 1 month that used antibiotic or bismuth therapy that was effective against H pylori. No information was given on age, sex, body mass index, smoking, duration of symptoms, referral pattern, diagnostic workup, or comorbidity, making generalizability to the usual family practice setting difficult.

STUDY DESIGN AND VALIDITY: The literature search included MEDLINE (1984-1999, all languages, through 2 databases), gastroenterology meeting abstracts, reference lists from review and other articles, and consultation with manufacturers of H pylori medications, a working consensus panel, and other experts. Information on the study sample, intervention, study design, study duration, quality, and outcomes was obtained by 2 investigators independently; agreement was excellent (k=0.92) for methodologic quality, and differences were resolved by consensus. This systematic review was well done. Its strengths included the thorough search and the quality of the review process. A major weakness is the use of a symptom-based diagnostic category (nonulcer dyspepsia), which recent studies have suggested does not discriminate efficiently between specific diseases. When combined with the absence of information about the subjects, it is difficult to know what clinical population is being treated. Other weaknesses include the lack of information on studies for which only abstracts were found and the lack of assessment of the impact of age, obesity, duration of symptoms before treatment, and other factors that might affect the outcomes measured.

OUTCOMES MEASURED: The primary outcome was improvement of symptoms. A secondary analysis addressed eradication of H pylori and its relationship to symptomatic improvement. The article did not address other outcomes important in primary care of patients with dyspepsia, such as medication cost, medication side effects, or impact on function or quality of life.

RESULTS: Ten studies (7 published studies and 3 abstracts) were found, but only 7 provided information on treatment success at 1 month. The available data did not permit calculation of an effect size for symptoms. Formal testing for heterogeneity of effect was statistically significant (P=.04). The authors did not provide an explanation for this heterogeneity, calling into question the validity of aggregating the data. The absolute difference between treatment and control groups ranged from 5% in favor of the control group to 20% in favor of the treatment group, and only one trial achieved a statistically significant difference. A pooled odds ratio found no significant differences between treatment and control groups; sensitivity analysis addressing methodologic quality, precision of definition of dyspepsia, and duration of follow-up did not change this finding.