there is evidence that the use of COX-2 inhibitors leads to a reduced incidence of dyspepsia by 2% to 3% (1)
the frequency of potentially serious gastrointestinal complications (e.g. bleeding or perforation) is approximately 1% with conventional NSAID treatment - the use of COX-2 inhibitors seems to lower this risk by 0.5.% to 1% (1)
this evidence means that 100 to 200 "typical" patients need to be treated (NNT) with a COX-2 inhibitor rather than a conventional NSAID to prevent one serious gastro-intestinal complication. In patients at low risk of gastrointestinal complications, the NNT to prevent a serious complication may be about 500 (2)
a MeReC review stated that (3)
cox-2 inhibitors, as a class, are associated with a lower GI risk than traditional NSAIDs. However, their GI-safety advantage is diminished when co-administered with aspirin
of the traditional NSAIDS, low-dose ibuprofen is associated with a lower GI risk than diclofenac and naproxen
use of a proton pump inhibitor (PPI) with any NSAID significantly reduces the risk of GI side effects
benefits from gastroprotection largely depend on the baseline risk that the individual has for GI complications. There is, as yet, very little direct evidence that adding a PPI to a cox-2 inhibitor is more beneficial than adding a PPI to a traditional NSAID
(1) Henry D, McGettigan P.Commentary on "Rofecoxib caused fewer endoscopic gastroduodenal ulcers than ibuprofen in osteoarthritis". Evidence Based Medicine 2000 May-June, 5 (3), 74. Comment on: Laine L, Harper S, Simon T et al, for the Rofecoxib Osteoarthritis Endoscopy Study Group. A randomized trial comparing the effect of rofecoxib, a cyclo-oxygenase 2-specific inhibitor, with that of ibuprofen on the gastroduodenal mucosa of patients with osteoarthritis. Gastroenterology 1999; 117: 776-83.
(2) Emery P, Seidler H, Kvien TK et al. Celecoxib versus diclofenac in long-term management of rheumatoid arthritis: randomised double-blind comparison. Lancet 1999;354; 2106-11.