Background: Many drugs increase the risk for gastroduodenal ulcer bleeding. The aim of this study was to investigate Helicobacter pylori infection and drug use in patients who had gastroduodenal ulcer bleeding in 2002 or 2007, and possible differences between the periods.

Material and methods: Patients with gastroduodenal ulcer bleeding were prospectively included in the periods 1.1 - 31.12. 2002 and 1.1 - 31.12. 2007. Information was recorded about Helicobacter pylori infection and intake of NSAIDs (non steroidal anti-inflammatory drugs), acetylsalicylic acid, warfarin, clopidogrel, low-molecular heparine, SSRIs (selective serotonin reuptake inhibitors), corticosteroids, paracetamol and proton pump inhibitors. Inhabitants in Oslo age >or= 60 years in 2007, were used as a control for drug use.

Results: 78.2 % of patients in 2002 and 90.7 % of those in 2007 used at least one of the drugs (p = 0.01). In 2002, 25.7 % of patients used non-selective NSAIDs and in 2007 46.1 % used such drugs (p = 0.001). In 2002, 36.7 % of patients used more than one of the studied drugs, versus 50.9 % in 2007 (p = 0.02). Compared to controls, the patients used more NSAIDs, acetylsalicylic acid, clopidogrel, low- molecular heparine, SSRIs and corticosteroids. Helicobacter pylori infection was diagnosed in 51.0 % of patients in 2002, versus 41.1 % in 2007 (p = 0.11).

Interpretation: Most patients with gastroduodenal ulcer bleeding use drugs that have a known risk of adverse effects such as ulcer and/or gastrointestinal bleeding.