Lower urinary tract symptoms (LUTS) are common in males over the age of 40 years old and are likely to increase with an aging population [1]. One of the main causative factors of LUTS is increased volume of the prostate gland [2]. IPSS is commonly used in the diagnosis of LUTS; it reveals the severity of LUTS with objective criteria [2]. The aim of this study is to evaluate the correlation between prostate morphology and IPSS scores in patients with lower urinary tract symptoms (LUTS).

This is a IRB approved prospective study. Sixty seven male patient with LUTS who presented to our clinic from August 2016 to July 2018 were included. Exclusion criteria are urethral stricture, idiopathic urinary retention, neurogenic bladder, underactive bladder, prostatic cancer, previous medical treatment of LUTS, previous prostatic surgery, bladder cancer and patients who are receiving or previously received pelvic radiotherapy. All patients underwent basic evaluation of LUTS including detailed history, international prostatic symptoms score (IPSS), urinary flow rate and post void residual (PVR), urinalysis, PSA and digital rectal examination (DRE). Measurement of the prostate volume configuration was performed by Transrectal ultrasound that was done by a single radiologist who was unaware of the clinical findings.SAS 9.4 (SAS Institute, Cary NC) was used perform the statistical analyses. Descriptive statistics of the clinical and demographic variables were provided. Counts and proportions were provided for categorical variables. Mean, standard deviation, median, min and max were calculated for continuous variables.

Exploratory analyses were conducted. Pearson’s correlations between IPSS sum score and other continuous variables were calculated.  Associations between IPSS sum score and categorical variables were examined using ANOVA models. Similar exploratory analyses were conducted between quality of life score and variables of interest. Scatterplots were created to visually assess the relationships.

Linear regression models were built to examine the effect of variables on the outcomes. Two sets of regression models were built, with IPSS sum score and quality of life score as the outcomes, respectively. Both univariate and multiple regression analyses were performed. Normality of residuals assumptions were checked and met.

There was a medium correlation between IPSS sum score and PVR (ρ=0.35, p=0.01), and a large correlation between IPSS sum score and quality of life score (ρ=0.52, p<0.01). IPSS sum score was not correlated with prostate size, TZ zone volume, TZ to prostate size ratio, QMAX, age, voiding volume, hyperplasia or median lobe.
Similarly, there existed a medium correlation between quality of life score and PVR (ρ=0.33, p=0.02). There was no significant correlations between quality of life score and prostate size, TZ zone volume, TZ to prostate size ratio, QMAX, age, voiding volume, hyperplasia or median lobe.

In the current prospective study we presented the correlation between the morphology of the prostate in BPH and the LUTS based ont he IPSS.
Univariate linear regression models were built to examine the associations between IPSS sum score and clinical variables of interest. PVR and quality of life score were significantly associated with the outcome IPSS sum score. Specifically, as PVR increases by 1 unit, IPSS sum score increases by 0.04 unit (β=0.04, p=0.01). As quality of life score increases by 1 unit, IPSS sum score increases by 2.49 unit (β=2.49, p<0.0001). Multiple regression analysis was performed and QMAX, PVR, Age, Voiding volume and IPSS sum score were included. As quality of life score increase by 1 unit, IPSS sum score increases by 2.62 unit (p=0.0001), while adjusting for the effect of QMAX, PVR, age and voiding volume. PVR was no longer significant in the presence of quality of life score.
Linear regression analyses were also conducted with quality of life score as the outcome.  Univariate models suggested that PVR and IPSS sum score were significantly associated with the outcome quality of life score. As PVR increases by 1 unit, quality of life score increases by 0.008 unit (β=0.008, p=0.02). As IPSS sum score increases by 1 unit, quality of life score increases by 0.11 unit (β=0.11, p<0.0001). QMAX, PVR, Age, Voiding volume and IPSS sum score were included in the multiple regression analyses. As IPSS sum score increases by 1 unit, quality of life score increases by 0.11 unit (p=0.0001), while adjusting for the effect of QMAX, PVR, Age and voiding volume. PVR was no longer significant in the presence of IPSS sum score.

In the presetn study there  a medium correlation between IPSS sum score and PVR (ρ=0.35, p=0.01), and a large correlation between IPSS sum score and quality of life score (ρ=0.52, p<0.01). IPSS sum score was not correlated with prostate size, TZ zone volume, TZ to prostate size ratio, QMAX, age, voiding volume, hyperplasia or median lobe.

Mangat R, Ho HSS, Kuo TLC. Non-invasive evaluation of lower urinary tract symptoms (LUTS) in men. Asian J Urol. 2017;5(1):42–47. doi:10.1016/j.ajur.2017.12.002
Aldo E. Calogero, Giovanni Burgio, Rosita A. Condorelli, Rossella Cannarella, Sandro La Vignera. (2018) Treatment of lower urinary tract symptoms/benign prostatic hyperplasia and erectile dysfunction. The Aging Male 21:4, pages 272-280.