Global 
Deutschland Esophagus to Small Intestine
JAMA. 2025;334(13):1160-1169
Helicobacter pylori screening after acute myocardial infarction: The cluster randomized crossover HELP-MI SWEDEHEART trial
Importance: Upper gastrointestinal bleeding is common after myocardial infarction.
Objective: To determine whether routine screening for Helicobacter pylori infection during hospitalization for myocardial infarction reduces bleeding events and improves clinical outcomes.
Design, setting, and participants: A nationwide, open-label, 2-period, 2-sequence, cluster randomized, crossover clinical trial using a clinical registry for study population definition and data collection merged with national Swedish health data registries. From November 17, 2021, through January 17, 2024, thirty-five Swedish hospitals grouped into 18 clusters were randomized to a sequence of 1 year with routine H. pylori screening of all patients with acute myocardial infarction followed by a washout period of 2 months before crossing over to 1 year with usual care or vice versa. Patients were followed up until January 17, 2025.
Intervention: Routine addition of H. pylori screening by urea breath test to standard care in all patients hospitalized for myocardial infarction during the screening periods. Main outcome and measure: Upper gastrointestinal bleeding, analyzed by a negative binomial model in the intention-to-treat population.
Results: A total of 18,466 patients (median age, 71 years [IQR, 61–79], 13,138 males [71%]) with myocardial infarction were followed up: 9,245 during the screening periods and 9,221 during the nonscreening periods. At admission, 2,284 during the screening periods and 2,275 during the nonscreening periods (both 24.7%) reported proton pump inhibitor use. During screening periods, 6,480 patients (70%) had undergone testing, of those 1,532 (23.6%) tested positive for H. pylori. After a median follow-up of 1.9 years, 299 patients in the screening group (incidence rate, 16.8 events per 1,000 person-years; cumulative hazard at 3 years, 4.1%) and 336 in the usual care group (incidence rate, 19.2 events per 1,000 person-years; cumulative hazard at 3 years, 4.6%) experienced the primary end point of upper gastrointestinal bleeding (rate ratio [RR] = 0.90; 95% CI: 0.77–1.05; p = 0.18). Predefined nonmultiplicity adjusted subgroup analyses showed a heterogeneous intervention effect; for no anemia (RR = 0.98; 95% CI: 0.80–1.21), mild anemia (RR = 0.64; 95% CI: 0.42–0.98), and moderate to severe anemia (RR = 0.44; 95% CI: 0.23–0.87; p for interaction = 0.03).
Conclusions and relevance: Among unselected patients with acute myocardial infarction, routine H. pylori screening did not significantly reduce the risk of upper gastrointestinal bleeding.