Patients with prostate cancer have an increased risk of stroke, but their absolute rate of stroke depends on age and comorbid conditions. The Charlson Comorbidity Index Score (CCIS) is a widely accepted measure for risk adjustment in administrative claims data sets. This study assesses the predictive value of CHADS2 scores and CCIS for stroke among patients with prostate cancer. The study was conducted based on data taken from Taiwan's National Health Insurance Research Database (NHIRD). We identified a total of 5414 participants with nonatrial fibrillation (AF) prostate cancer diagnoses who underwent radical prostatectomy between 1997 and 2011. CHADS2 scores and CCIS were used to stratify the 5-year ischemic stroke risk. All participants were followed from the date of enrollment until ischemic stroke, death, or the end of the 5-year follow-up period. The 5-year risk of ischemic stroke in the present study was 1.7%. Ischemic stroke has a better correlation with CHADS2 (CHADS2 score = 0 to 1: 0.02%, CHADS2 score = 2 to 3: 13.9%, CHADS2 score ≥ 4: 44.4%; AUC = 0.978) than CCIS (CCIS = 0 to 1: 1.6%, CCIS = 2 to 3: 1.7%, CCIS ≥ 4: 3.8%; AUC = 0.520). Our results show that patients with prostate cancer who underwent radical prostatectomy show significantly higher risk of ischemic stroke in high CHADS2 score patients, and the CHADS2 score could be applied for ischemic stroke prediction. Cardiovascular risks evaluation and management are suggested for prostate cancer patients with higher CHADS2 score.
Keywords: CHADS2 scores; ischemic stroke; predictor; prostate cancer; radical prostatectomy; risk.
© 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.