Incidence and risk of treatment for benign prostatic hyperplasia in Japanese men: A 15‐year longitudinal community‐based study. (29th October 2012) - Fukuta, Fumimasa
Abstract Objectives To determine the incidence of and the risk factors for treatment in Japanese men with benign prostatic hyperplasia/lower urinary tract symptoms enrolled into a longitudinal community‐based study. Methods A total of 267 of 319 men aged 40–79 years were eligible for this study, with nearly 15 years of follow up. Their medical records were checked to look for any medical treatment for benign prostatic hyperplasia/lower urinary tract symptoms. The risk of treatment for benign prostatic hyperplasia/lower urinary tract symptoms was determined by calculating the hazard ratio using the Cox proportional hazards model. Five baseline parameters were considered: the International Prostate Symptom Score, the peak urinary flow rate, the prostate volume, the serum prostate‐specific antigen and the internal prostatic architecture on transrectal ultrasonography. Results Data were successfully collected for 171 men (64%; 121 survivors and 50 deceased). During approximately 1900 person‐years of follow up, the overall incidence of treatment for benign prostatic hyperplasia/lower urinary tract symptoms was 15.4/1000 person‐years. All five parameters were statistically significant predictors of future treatment for benign prostatic hyperplasia/lower urinary tract symptoms: International Prostate Symptom Score greater than 7 (hazard ratio 6.2, P < 0.001), prostate volume greater than 30 mL (hazard ratio 4.3, P = 0.002), peak urinary flow rate less than 12 mL/s (hazard ratio 4.4, P < 0.001), prostate‐specific antigen greater than 1.4 ng/mL (hazard ratio 4.0, P < 0.001) and internal prostatic architecture group 3 (hazard ratio 3.2, P = 0.002). Conclusions Severity of lower urinary tract symptoms, decreased peak urinary flow rate, enlarged prostate volume, high prostate‐specific antigen value and internal prostatic architecture at baseline are independent risk factors for treatment in Japanese men presenting with benign prostatic hyperplasia/lower urinary tract symptoms.