A randomized controlled trial comparing sequential with triple therapy for Helicobacter pylori in an Aboriginal community in the Canadian North.

BACKGROUND: Helicobacter pylori infection occurs more frequently in Arctic Aboriginal settings than elsewhere in North America and Europe. Research aimed at reducing health risks from H pylori infection has been conducted in the Aboriginal community of Aklavik, Northwest Territories.

OBJECTIVE: To compare the effectiveness of the Canadian standard therapy with an alternative therapy for eliminating H pylori infection in Aklavik.

METHODS: Treatment-naive H pylori-positive individuals were randomly assigned to a 10-day regimen (oral twice-daily doses) with rabeprazole (20 mg): standard triple therapy (proton pump inhibitor, added clarithromycin [500 mg] and amoxicillin [1 g] [PPI-CA]); sequential therapy (ST) added amoxicillin (1 g) on days 1 to 5, and metronidazole (500 mg) and clarithromycin (500 mg) on days 6 to 10. Participants with clarithromycin-resistant H pylori were randomly assigned to ST or quadruple therapy. Treatment effectiveness was estimated as per cent (95% CI) with a negative urea breath test at least 10 weeks after treatment.

RESULTS: Of 104 (53 PPI-CA, 51 ST) randomized participants, 89 (49 PPI-CA, 40 ST) had post-treatment results. Per-protocol treatment effectiveness was 59% (95% CI 45% to 73%) for PPI-CA and 73% (95% CI 58% to 87%) for ST. Based on intention to treat, effectiveness was 55% (95% CI 41% to 69%) for PPI-CA and 57% (95% CI 43% to 71%) for ST. Of 77 participants (43 PPI-CA, 34 ST) with 100% adherence, effectiveness was 63% (95% CI 43% to 82%) for PPI-CA and 81% (95% CI 63% to 99%) for ST.

CONCLUSIONS: While additional evidence is needed to confirm that ST is more effective for Arctic Aboriginal communities than the Canadian standard H pylori treatment, these results show standard PPI-CA treatment to be inadequate for communities such as Aklavik.