Correlation between the total volume, transitional zone volume of the prostate, transitional prostate zone index and lower urinary tract symptoms (LUTS)

Currently available studies show controversial data between the symptoms of the lower urinary tract and the volume of the prostate gland. The objective of the present study is to evaluate the relationship between the score of the lower urinary tract symptoms assessed according to the International Prostate Symptoms Score (IPSS) and the total (TV) and transitional (TZV) zone volume of the prostate and transitional prostate zone index (TZI).

From 223 men with a mean age of 59.3 years (varying from 50 to 75), the scores of lower urinary tract symptoms, measured by the IPSS and TV and TZV, determined by transrectal ultrasonographies, were obtained. Furthermore, the TZI was determined in all cases by the TZV to TV rate of the prostate. The relationship between TV, TZV, and TZI and the data obtained using the symptoms score was statistically determined.

The TV of the prostate were 25.5 ± 10.3, 25.0 ± 9.3, and 28.9 ± 13.5 g in individuals with mild, moderate, and severe symptoms, respectively (P = 0.15). Similarly, there was no significant difference when the TZV (7.6 ± 6.3, 7.6 ± 5.8, and 9.6 ± 6.8 g, respectively; P = 0.22) and the TZI (0.26 ± 0.1, 0.27 ± 0.1, and 0.30 ± 0.1, respectively; P = 0.33) were compared in the groups of men with mild, moderate, and severe symptoms of urinary difficulty. However, the quality of life (QoL) scores presented progressively worse values (1.7 ± 1.3, 3.1 ± 1.4, and 4.4 ± 1.2) as the severity of the lower urinary tract symptoms became worse (P < 0.001). The Pearson correlation coefficient between the TV (r = 0.15; P = 0.02), TZV (r = 0.16; P = 0.02), and the TZI (r = 0.14; P = 0.03) with the prostate symptom scores showed low values although they were positive and statistically significant. The highest correlation was observed when the QoL related to urinary symptoms and symptom scores (r = 0.61; P < 0.001) was analyzed.

A low correlation was found between the score lower urinary tract symptoms assessed by IPSS and the different volumes of the prostate gland (TV, TZV) and prostate TZI, and, on the other hand, an inverse correlation between the intensity of urinary symptoms and QoL, supporting the idea of multifactorial aspects related to the genesis of urinary symptoms in men.