Nonsteroidal anti-inflammatory drugs and lower gastrointestinal complications

In addition to the upper GI tract, NSAIDs can damage the small bowel and the colon. NSAID enteropathy is frequent and may be present in more than 60% of patients taking these drugs long term. In most cases, damage is subclinical, including increased mucosal permeability, inflammation, erosions, ulceration, but other more serious clinical outcomes such as anemia, and overall bleeding, perforation, obstruction, diverticulitis and deaths have also been described. The magnitude of these serious outcomes from the lower GI tract is not well defined, but recent data suggest that they may be as frequent and severe as upper GI complications. Contrary to what happens in the upper GI tract, treatment and prevention of NSAID enteropathy is difficult, since the pathogenic mechanisms are different and not well understood. Among other options, misoprostol, antibiotics, and sulphasalazine have been proved to be effective in animal models, but they have not been properly tested in humans. Selective COX-2 inhibition is emerging as a potential alternative to tNSAIDs in the prevention of damage in the lower GI tract in rheumatologic patients. Preliminary studies in healthy volunteers have shown that these drugs are associated with no or less small bowel damage than tNSAIDs plus PPI, although their long-term effects in patients need to be properly tested. Post hoc analysis of previous outcome studies focused on complications of upper GI tract or cardiovascular events have shown contradictory results. Data from one ongoing trial comparing celecoxib versus diclofenac plus PPI and examining serious outcomes from the whole GI tract will probably provide new insights in this area.