Abstract
Background: Statins are commonly used cholesterol-lowering drugs with evidence of additional chemoprotective and immunomodulatory effects resulting from the inhibition of DNA replication, cell proliferation, and TH1-cell inhibition. There are conflicting reports regarding the potential benefit of concurrent statin treatment on non-muscle invasive bladder cancer (NMIBC) and specifically on intravesical Bacillus Calmette-Guerin (BCG) outcomes. We therefore aimed to analyze the effects of concurrent BCG and statin use in patients with NMIBC. Methods: National Veterans Affairs databases were used to retrospectively identify men with NMIBC between 2000 and 2010 who were treated with BCG. Pharmacy data was interrogated, and patients were divided according to statin therapy status. Statins had to be given at the beginning of BCG treatments and continued for at least 6 months. Cox proportional hazard ratios after inverse propensity score-weighted and competing risks adjustments were calculated for recurrence, secondary events (e.g., progression), cancer-specific survival, and overall survival. Results: Among 8814 patients, with a median follow-up of 11.3 years, statins were used by 38% of the patients. Patients taking statins were older (71 vs. 68, p < 0.0001), had more comorbidities (Charlson Comorbidity Index (CCI > 2; 38.6% vs. 31.4%, p < 0.0001), and had a higher-grade disease (40.2% vs. 34.3%, p < 0.0001) compared to those not on statins. After adjusting for stage, grade, age, race, CCI, agent orange exposure, and year of diagnosis, Cox proportional hazard analysis revealed no association with recurrence (HR 1.05, 95% CI 0.97-1.15, p = 0.23), secondary events (HR 0.91, 95% CI 0.80-1.05, p = 0.189), or bladder cancer specific survival (HR 0.88, 95% CI 0.76-1.02, p = 0.09) of statin use. However, statins were associated with improved overall survival (HR 0.89, 95% CI 0.83-0.96, p = 0.002). Conclusions: Concurrent statin and BCG use in patients with NMIBC was associated with improved overall survival, but not recurrence, secondary events, or bladder cancer-specific survival. These results confirm the real-world well-established cardiovascular benefit of statin treatment and primary preventive care. However, this large population study did not find any association between statins and the outcomes of patients with NMIBC treated with BCG immunotherapy.