The association of benign prostatic hyperplasia with lower urinary tract stones in adult men: A retrospective multicenter study

Objective: To examine the relationship between benign prostatic hyperplasia (BPH)and the presence of lower urinary tract stones. Methods: We retrospectively reviewed the records of men with lower urinary tract stones who presented to three clinical centers in Korea over a 4-year period. We divided the patients into two groups based on the location of urinary stones: Group 1 (bladder calculi)and Group 2 (urethral calculi). We compared the characteristics of both groups and performed univariate and multivariate analyses with a logistic regression model to investigate the relationship between BPH and lower urinary tract stones. Results: Of 221 patients, 194 (87.8%)had bladder calculi and 27 (12.2%)had urethral calculi. The mean age of Group 1 was higher than that of Group 2 (68.96 ± 12.11 years vs. 55.74 ± 14.20 years, p < 0.001). The mean prostate volume of Group 1 was higher than that of Group 2 (44.47 ± 27.14 mL vs. 24.70 ± 6.41 mL, respectively, p < 0.001). Multivariate logistic regression showed that age (OR = 1.075, 95%CI: 1.023–1.129)and prostate volume (OR = 1.069, 95%CI: 1.017–1.123)were independently associated with increased risk for bladder calculi. Upper urinary tract stones and/or hydronephrosis conferred a 3-fold risk for urethral calculi (OR = 3.468, 95%CI: 1.093–10.999). Conclusion: Age and prostate volume are independent risk factors for bladder calculi. In addition, men with upper urinary tract disease are at greater risk for urethral calculi, which may migrate from the upper urinary tract rather than from the bladder.