Thiazolidinedione use and ulcerative colitis-related flares: an exploratory analysis of administrative data.

BACKGROUND: Recent animal studies and clinical trials suggest that thiazolidinediones, a class of oral antidiabetic agents, are efficacious in reducing inflammation, yet no studies have evaluated their effectiveness in preventing flares. We examined the association between thiazolidinedione use and ulcerative colitis (UC)-related flares.
METHODS: We conducted a retrospective cohort study using administrative data from 87 health plans across 33 states. Individuals with both UC and diabetes were identified using administrative definitions. Exposure to thiazolidinediones or other oral antidiabetic agents was ascertained through outpatient pharmacy claims. The primary outcome was occurrence of a UC flare defined by: 1) a new prescription for oral steroids, infliximab, or oral/rectal salicylates, or 2) a claim for colectomy. Secondary analyses analyzed outcomes separately. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression after matching each thiazolidinedione user to a comparable oral antidiabetic user on propensity score.
RESULTS: This study included 142 thiazolidinedione and 468 other oral antidiabetic users with a mean follow-up of 7.3 and 6.2 months, respectively. Thiazolidinedione use was not associated with UC-related flares as measured by the composite outcome (HR = 1.05, 95% CI: 0.66, 1.68). However, thiazolidinedione use was associated with a nonsignificant reduction in risk of oral steroid use when analyzed as a separate outcome (HR = 0.53, 95% CI: 0.20, 1.44).
CONCLUSIONS: Thiazolidinediones do not provide any benefit over other oral antidiabetics in preventing UC-related flares as measured by our primary composite outcome. However, thiazolidinedione use may reduce the risk of more significant disease flares requiring oral steroid treatment.