Risk of prostate and bladder cancers in patients with spinal cord injury: A population-based cohort study¹

Objective: To evaluate the risk of prostate and bladder cancers in patients with spinal cord injury (SCI). Materials and methods: We used data obtained from the National Health Insurance system of Taiwan for this study. The SCI cohort contained 54,401 patients with SCI, and each patient was randomly frequency matched with 4 people from the general population (without SCI) based on age, sex, and index date. Incidence rates, SCI cohort to non-SCI cohort rate ratios, and hazard ratios were measured to evaluate the cancer risks. Results: Patients with SCI showed a significantly lower risk of developing prostate cancer compared with subjects without SCI (adjusted hazard ratio = 0.73; 95% confidence interval = 0.59, 0.90), after accounting for the competing risk of death. No significant difference in the risk of bladder cancer emerged between the SCI and control groups. Further analyses found a higher spinal level of SCI tended to predict a lower risk for prostate cancer. Conclusions: Patients with SCI incurred a lower risk for prostate cancer compared with people without SCI. The risk for bladder cancer did not differ between people with or without SCI.