Abstract
Lower urinary tract symptoms (LUTS) are common in older men and are frequently associated with benign prostatic hyperplasia (BPH). The relationship between BPH and endogenous total testosterone (TT) levels has been widely studied. The aim of this post hoc analysis was to determine the association between LUTS and endogenous TT levels in a subset of men participating in the 2013 Prostate Cancer Awareness Week, a U.S. community-based prostate cancer screening program. Men completed the International Prostate Symptom Score (I-PSS) questionnaire, prostate size was estimated by a digital rectal examination, and serum TT and prostate-specific antigen levels were measured. Mean TT levels (ng/dl) did not significantly correlate with prostate size category (
Keywords
Introduction
Lower urinary tract symptoms (LUTS) are common in older men, with the prevalence of moderate-to-severe LUTS ranging from 22% in men aged 50 to 59 years to 45% in men aged 70 to 80 years (Rosen et al., 2003). LUTS comprise storage (irritative) symptoms (i.e., urinary frequency, nocturia, urgency, urinary incontinence) and voiding (obstructive) symptoms (i.e., slow-stream, intermittency, hesitancy, straining, postmicturition dribble, and sensations of incomplete emptying). LUTS may result from a complex interplay of pathophysiological influences, including prostatic pathology and bladder dysfunction (Chapple & Roehrborn, 2006).
Benign prostatic hyperplasia (BPH), a nonmalignant proliferation of the epithelial and stromal cells, leads to prostate enlargement, primarily in older men. Prostatic cell proliferation and the development of histological features of BPH are generally considered to be dependent on the bioavailability of testosterone and its metabolite, 5α-dihydrotestosterone. An association between these androgens levels and BPH measures has not been consistently reported. Because of the known effects of androgens on prostate growth, testosterone prescribing information warns that the therapy may worsen BPH symptoms, and clinicians are advised to monitor patients with BPH who are receiving testosterone replacement therapy (TRT) for worsening of signs and symptoms of BPH (Bhasin et al., 2010).
While the association between BPH and endogenous total testosterone (TT) levels has been widely studied, there is less clarity on the effects of endogenous TT levels on LUTS. (Pearl et al., 2013, Yassin, El-Sakka, Saad, & Gooren, 2008). The aim of this post hoc analysis was to study the relationship, if any, between TT level and both prostate size, estimated by digital rectal examination (DRE), and LUTS, as assessed by the International Prostate Symptom Score (I-PSS).
Method
The study sample comprised men who elected to be screened during the 2013 Prostate Cancer Awareness Week (PCAW). PCAW is a U.S. community-based prostate cancer screening program, sponsored by the Prostate Conditions Educational Council, with approval provided by Colorado Multiple Institutional Review Board. Men are offered the opportunity to attend PCAW during the third week of September, with recruitment through media announcements and information posted on the Prostate Conditions Educational Council website. Methodology of PCAW has been previously published in detail (Stone, Miner, Poage, Patel, & Crawford, 2014). Men undergoing screening (
Baseline Characteristics (Men With a Blood Draw Time From 8 to 11 a.m.,
Categorized based on the opinion of the examiner.
Results
There were no significant correlations between mean TT level and prostate size (r = +.03,
Total Testosterone Level by Prostate Size and Measures of Lower Urinary Tract Symptoms.
Categorized based on the opinion of the examiner.
Discussion
In this analysis, endogenous TT levels did not correlate with prostate size, PSA level, or LUTS. The findings are consistent with an earlier study, using a similar group of men, which concluded that testosterone levels had no impact on LUTS status, PSA level, or prostate volume (Schatzl et al., 2000).
These findings may add support to the saturation theory, which postulates that increased levels of testosterone do not further induce androgen-stimulated prostate tissue proliferation due to receptor saturation (Khera, Crawford, Morales, Salonia, & Morgentaler, 2014). While this study assessed only endogenous TT levels, these data suggest that worsening of LUTS following TRT in hypogonadal men may be related to stimulation of prostatic cells previously deprived of testosterone.
Study limitations include the following: the use of a community-based study of relatively small sample size (
Footnotes
Declaration of Conflicting Interests
The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: AN, DAP, SAD, and DM are salaried employees at Eli Lilly and Company; EDC is a consultant for Bayer, Inc MDx, Genomic Health Jansen Pharmaceuticals, Dendreon, and Ferring Pharmaceuticals; WP is a collaborator/contractor with MDx Health, Strand Diagnostics, Genomic Dx, Abbott Laboratories, and Bayer, Inc.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The analyses were performed by Eli Lilly and Company
