Risk of Venous Thromboembolism With Gout Flares.

Abstract

Previous studies demonstrated that the risk of venous thromboembolism (VTE) is increased in patients with gout, but not whether there was a temporal association between gout flare and VTE. This study was undertaken to evaluate potential temporal associations between gout flare and VTE. Data were obtained from electronic primary-care records from the UK's Clinical Practice Research Datalink, which links data from hospitalization and mortality registers. Using self-controlled case series analysis adjusted for season and age, we evaluated the temporal association between gout flare and VTE. The 90 days after primary-care consultation or hospitalization for gout flare was designated the exposed period. This was divided into three 30-day intervals. The baseline period was up to 2 years before the start of and up to 2 years after the end of the exposed period. The association between gout flare and VTE was measured using adjusted incidence rate ratios (IRRs) with 95% confidence intervals (95% CIs). In total, 314 patients met the inclusion criteria (age ≥18 years, incident gout, no presence of VTE or use of a primary-care anticoagulant prescription before the start of the pre-exposure period). Among the 314 patients, VTE incidence was significantly higher in the exposed period than in the baseline period (adjusted IRR 1.83, 95% CI 1.30-2.59). The adjusted IRR of VTE during the first 30 days after gout flare was 2.31 (95% CI 1.39-3.82) relative to the baseline period. No increase in the adjusted IRRs was observed in days 31-60 (adjusted IRR 1.49, 95% CI 0.79-2.81) and days 61-90 (adjusted IRR 1.67, 95% CI 0.91-3.06) relative to baseline. Results were consistent across sensitivity analyses. Among patients with gout, there was a transient increase in the rate of VTE within 30 days after primary-care consultation or hospitalization for gout flare.