NASHVILLE, Tenn.—In an analysis of the results of interventions to eradicate the bacterium Helicobacter pylori (a risk factor for gastric cancer) in seven diverse community populations in Latin America, researchers found that geographic site, demographic factors, adherence to initial therapy and infection recurrence may be as important as the choice of antibiotic regimen in H pylori eradication interventions, according to a study appearing in the February 13 issue of the Journal of the American Medical Association (JAMA).
“Gastric adenocarcinoma is the second leading cause of cancer death worldwide," according to background information in the article. "Although gastric cancer rates are declining in some areas, the number of deaths is expected to increase over the coming decades due to growing and aging populations in high-incidence regions such as Latin America and eastern Asia.
"Helicobacter pylori infects more than half of the world's adult population, and chronic infection with this bacterium is the dominant risk factor for gastric cancer, accounting for an estimated two-thirds of all cases globally," the article continued. "The feasibility of large-scale programs is uncertain and success in specific populations will depend on the efficacy of the antibiotic regimen used and the risk of recurrent infection following eradication."
Douglas Morgan, MD, MPH, of Vanderbilt Medical Center, Nashville, Tenn., and colleagues estimated risk of H pylori recurrence and assessed factors associated with successful eradication 1 year after treatment with one of three regimens. The study included 1,463 participants, 21 to 65 years of age from 7 Latin American communities, who were treated for H pylori and observed between September 2009 and July 2011.
Potential participants were selected using a census of households (Colombia, Costa Rica, Nicaragua), a large public clinic registry (Chile), or household recruitment (Honduras and 2 sites in Mexico). Participants were randomized to 1 of 3 treatment groups: 14-day lansoprazole, amoxicillin, and clarithromycin (triple therapy); 5-day lansoprazole and amoxicillin followed by 5-day lansoprazole, clarithromycin, and metronidazole (sequential); or 5-day lansoprazole, amoxicillin, clarithromycin, and metronidazole (concomitant).