Tegaserod and the Risk of Cardiovascular Ischemic Events: An Observational Cohort Study

Abstract

Tegaserod, a partial 5-HT(4) agonist previously approved for treatment of irritable bowel syndrome with constipation and chronic idiopathic constipation, was suspended from US marketing in 2007, based on pooled clinical trial results which contained a signal suggesting increased risk of cardiovascular ischemic events (CVIEs). We sought to evaluate whether there was an association between tegaserod and CVIE in a setting of routine clinical practice. This was a matched cohort study conducted within a large US health insurance database, involving 52 229 patients who initiated tegaserod and 52 229 patients with similar characteristics who did not initiate tegaserod. Participants were followed for up to 6 months for the occurrence of CVIE (myocardial infarction, acute coronary syndrome, coronary revascularization, and stroke). Outcomes were identified using insurance claims and were confirmed by review of medical records. We conducted as-matched analyses providing hazard ratios (HRs) along with 95% confidence intervals (95% CI) and as-treated analyses accounting for changes in dispensed therapy. There was no increased risk of CVIE associated with tegaserod treatment. The as-matched association between tegaserod and ischemic cardiovascular outcomes (HR = 0.95, 95% CI 0.73-1.23) and stroke (HR = 0.90, 95% CI 0.46-1.77) did not change substantially in the as-treated analyses (cardiovascular relative risk [RR] = 1.14, 95% CI 0.83-1.56; stroke: RR = 1.09, 95% CI = 0.49-2.02). The results were largely unaffected by adjustment for characteristics or subgroup analyses. In this observational study of tegaserod use, we found no evidence for an increased risk of CVIE in tegaserod users.