ABSTRACT
BACKGROUND: Pretreatment antimicrobial resistance has an important impact on the efficacy of many Helicobacter pylori treatment regimens. OBJECTIVE: To estimate the prevalence of H. pylori resistance to antimicrobials in the United States, to characterize risk factors associated with H. pylori antimicrobial resistance, and to explore the association between drug utilization and antimicrobial resistance patterns over time. DESIGN: Meta-analysis using patient-level data. SETTING: 20 nationwide trials of H. pylori eradication. PATIENTS: 3624 men and women, each of whom contributed one isolate. MEASUREMENTS: Rates of H. pylori resistance to clarithromycin, metronidazole, and amoxicillin, according to geographic region, age, sex, study year, ethnicity, ulcer status, test method, and study. RESULTS: Overall resistance to clarithromycin, metronidazole, and amoxicillin was 10.1% (95% CI, 9.1% to 11.1% [360 of 3571 patients]), 36.9% (CI, 35.1% to 38.7% [1063 of 2883 patients]), and 1.4% (CI, 1.0% to 1.8% [48 of 3486 patients]), respectively. In multivariable analyses, multiple risk factors were associated with resistance to individual agents. Clarithromycin resistance was significantly associated with geographic region (P = 0.050), older age (P < 0.001), female sex (P < 0.001), inactive ulcer disease (P < 0.001), and study (P = 0.010). Metronidazole resistance was significantly associated with female sex (P < 0.001), earlier year of study enrollment (P = 0.036), Asian ethnicity (P < 0.001), use of an epsilometer test (P = 0.002), and study (P < 0.001). Amoxicillin resistance was low and was not significantly associated with any risk factor. In the 1990s, when rates for use of oral macrolides and metronidazole were relatively stable, clarithromycin resistance rates were stable and metronidazole resistance rates varied. CONCLUSIONS: Clinicians should consider risk factors for antimicrobial resistance when deciding which patients should have susceptibility testing and when choosing appropriate H. pylori treatments in the empirical setting.
