Risk factors for NSAID-induced ulcers

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used and commonly cause adverse effects. Upper abdominal pain or discomfort has been reported in up to a half of NSAID users, but symptom analysis cannot reliably distinguish between NSAID-related dyspepsia and pain due to peptic ulceration. About 15 to 30% of NSAID users have ulcers visible at endoscopy, but many are asymptomatic until a complication such as anaemia, bleeding or perforation occursLaine, 2003.

Over-the-counter preparations of NSAIDs may cause dyspepsia, but their risk of causing ulcer and bleeding appears to be lower than for prescribed NSAIDs, because of their lower dose, shorter half-life and generally shorter duration of use.

Although the overall risk of a serious NSAID-induced gastrointestinal adverse event such as overt bleeding or perforation is relatively low, some patients are at much higher risk (see Risk factors for NSAID-induced upper gastrointestinal bleeding or perforation).

The relative risk of an NSAID causing a serious gastrointestinal adverse event is influenced by:

• half-life—NSAIDs with a longer half-life (eg piroxicam) are more likely to cause serious gastrointestinal complications
• dose and duration of therapy—higher doses and longer courses of therapy increase the risk of ulcer and bleeding
• cyclo-oxygenase (COX) selectivity—COX-2–selective NSAIDs (eg celecoxib) reduce, but do not abolish, the risk of ulcer disease and complications compared with COX-1–selective NSAIDs (eg aspirin) or nonselective NSAIDs (eg diclofenac, ibuprofen)
• patient-specific risk factors (see Figure 6.2), including concurrent Helicobacter pylori infection.