Long-term NSAID use and incident urothelial cell carcinoma in the VITamins and Lifestyle (VITAL) study.

PURPOSE

Literature on the chemopreventive role of nonsteroidal anti-inflammatory drugs (NSAIDs) in urothelial carcinoma of the bladder (UC) is conflicting. A recent pooled analysis of 3 cohorts reported regular use of nonaspirin NSAIDs was associated with reduced risk of urothelial carcinoma (UC) among nonsmokers only; however, nonsmokers are a group with a low risk of UC. We examine the association between NSAID use and UC risk.

MATERIALS AND METHODS

Study participants were members of the VITamins and Lifestyle (VITAL) cohort of 77,048 Washington State residents aged 50-76 years who completed a baseline questionnaire in 2000-2002 on NSAID use and cancer risk factors. Ten-year use of aspirin and other NSAIDs was categorized as none, low-use (1-3 d/wk or <4 years), or high-use (≥ 4 d/wk and ≥ 4 years). Incident UC cases were prospectively identified via linkage to a local cancer registry. Hazard ratios (HR) were estimated by multivariate Cox regression.

RESULTS

A total of 385 incident cases of UC were diagnosed over a mean follow-up of 7 years. There was no association with NSAID use and risk of UC. However, the association of use of nonaspirin NSAIDs with UC risk differed by smoking status (P for interaction = 0.02). Specifically, among long-term former smokers (quit ≥ 10 years), nonaspirin NSAID use was associated with a 31% reduction in risk of UC in low-users (HR 0.69, 95% CI 0.46-1.04), and 48% reduction in risk for high-users (HR 0.52, 95% CI 0.24-1.11, P for trend = 0.02).

CONCLUSIONS

Our results show a risk reduction with nonaspirin NSAID use among long-term quitters, a group with significant risk of UC.