Prostate volume growth rate changes over time: Results from men 18 to 92 years old in a longitudinal community-based study.

Previous investigations have shown that changes in total prostate volume (TPV) are highly variable among aging men, and a considerable proportion of aging men have a stable or decreasing prostate size. Although there is an abundance of literature describing prostatic enlargement in association with benign prostatic hyperplasia, less is known about the appropriate age cut-off points for TPV growth rate. In this community-based cohort study, TPV was examined once a year in men who had consecutive health checkup, during a follow-up of 4 years. A total of 5058 men (age 18-92 years old) were included. We applied multiple regression analyses to estimate the correlation between TPV growth rate and age. Overall, 3232 (63.9%) men had prostate growth, and 1826 (36.1%) had a stable or decreased TPV during the study period. The TPV growth rate was correlated negatively with baseline TPV (r=-0.32, P<0.001). Among 2620 men with baseline TPV <15 cm3, the TPV growth rate increased with age (β=0.98, 95% CI: 0.77%-1.18%) only up to 53 years old. Among 2188 men with baseline TPV of 15-33.6 cm3, the TPV growth rate increased with age (β=0.84, 95% CI, 0.66%-1.01%) only up to 61 years old after adjusting for factors of hypertension, obesity, baseline TPV, diabetes mellitus and dyslipidemia. In this longitudinal study, the TPV growth rate increased negatively with baseline TPV, only extending to a certain age and not beyond. Further research is needed to identify the mechanism underlying such differences in prostate growth.