Relationship between age, prostate volume, prostate-specific antigen, symptom score and uroflowmetry in men with lower urinary tract symptoms

Abstract

Objectives: To estimate the relationship between age and the values of different diagnostic tests in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic enlargement (BPE) and to compare prostate growth curves between the normal population sample, healthy men and men with LUTS.

Material and methods: A series of 354 men (mean age 70.2 years; range 45-91 years) with LUTS due to BPE were stratified into seven age groups and reviewed retrospectively. All patients underwent a standard evaluation, involving determination of the International Prostate Symptom Score (IPSS), digital rectal examination, uroflowmetry, determination of the prostate-specific antigen (PSA) level and transrectal ultrasonography. Descriptive statistics were used to describe all the variables and Spearman's correlation test was used to evaluate the relationships between them.

Results: The mean prostate volume was 40.1 (+/-23.9) cm(3) and mean PSA concentration 3.9 (+/-4.2) ng/ml. Both values increased progressively from 27.5 ml and 1.5 ng/ml, respectively in the <54 years age group to 48.2 ml and 5.4 ng/ml, respectively in the <80 years age group. However, in the 75-79 years age group there was a decrease in both prostate volume and symptom score; PSA concentration remained unchanged and maximal flow rate increased slightly. A statistically significant but weak correlation was found between prostate volume and age (r = 0.25, p < 0.0001) and between PSA and age (r = 0.28, p < 0.0001). Prostate volume correlated positively with serum PSA (r = 0.54, p < 0.0001). The correlations between maximum flow rate and age, prostate volume, PSA and IPSS were r = -0.21, p < 0.0001; r = -0.18, p < 0.0006; r = -0.29, p < 0.0001; and r = 0.14, p < 0.0098, respectively.

Conclusions: These data confirm that prostate volume and serum PSA concentration are significantly correlated and increase with advanced age. The correlations between uroflowmetry (Qmax) and age, prostate volume, serum PSA and IPSS were also significant. However, there was no relationship between symptoms and objective measures of BPE. The increase in different parameters of the severity of benign prostatic hyperplasia with advanced age is not continuous. The prostate volume alone is not useful in the estimation of disease severity.