An analysis of various risk factors in the VIGOR trial indicated a risk reduction of 88% in the low-risk subgroup, 51% in the high-risk subgroup and 54% in the intermediate-risk subgroup. The risk factors that were significantly associated with gastrointestinal events included age, prior history of clinical gastrointestinal events (complicated or uncomplicated), disease severity, duration of disease, prior history of gastrointestinal symptoms, and prior use of low dose H2RAs, steroids or NSAIDs.
USE OF ASA
ASA is widely used for cardiovascular prophylaxis but is a clearly identified risk factor for gastrointestinal hemorrhage. A meta-analysis of 24 randomized, controlled trials that recruited 66,000 patients reported that 2.5% of patients receiving ASA experienced gastrointestinal hemorrhage, compared with 1.4% taking placebo. In subjects who were receiving lower doses of ASA (less than 163 mg/day), the incidence of bleeding fell slightly to 2.3%, compared with 1.5% in the placebo group. However, a meta-regression suggested that there was no relationship between gastrointestinal hemorrhage and ASA dose, and no benefit of modified release formulations. Buy drugs with confidence – buy levaquin 500 mg to see how cheap your treatment can be.
Although an increased incidence of upper gastrointestinal bleeding has been reported in patients coprescribed low dose ASA and NSAIDs, only the CLASS and Successive Celecoxib Efficacy and Safety Study (SUCCESS-I) have attempted to look at this issue prospectively. The CLASS study reported a lower risk of PUBs in patients receiving a coxib plus ASA than in those receiving an NSAID plus ASA, although this study was not powered to detect these differences. Moreover, the difference in the rate of complicated ulcers was very small. Although no statistical analysis was presented in the abstract of the SUCCESS-I study, in this patient subgroup, a reduction was seen in the coxib-treated group for all outcomes studied. Compared with conventional NSAIDs, coxib use resulted in a risk reduction of 30% to 88% in serious upper gastrointestinal events in non-ASA users compared with 43% to 63% in ASA users. It remains to be determined from appropriately designed, prospective studies whether there is a true difference between these two treatment groups.