Benign prostatic hyperplasia (BPH) represents a prevalent condition among aging males, frequently leading to lower urinary tract symptoms (LUTS) and significant morbidity. Bladder outlet obstruction (BOO), a common consequence of BPH, often coexists with detrusor overactivity (DO), presenting challenges in clinical management and treatment outcomes. Moreover, emerging evidence suggests a close association between BPH and prostatic inflammation (PI), further complicating the clinical picture. Despite advancements in therapeutic modalities, including pharmacotherapy and surgical interventions such as transurethral prostatectomy (TURP), the interplay between DO and PI in the context of BOO secondary to BPH remains poorly understood.
This study aimed to address this knowledge gap by investigating the potential correlation between DO and PI in patients presenting with BOO secondary to BPH.

This study, characterized by its prospective, observational, and comparative design, was carried out under the auspices of the Urodynamics Clinic within our department following approval from the Local Ethics Committee. Participants were men presenting with lower urinary tract symptoms attributable to BPH who had undergone either alpha-blocker monotherapy or a combination of 5-alpha reductase inhibitors (5ARI). Eligible individuals exhibited an International Prostate Symptom Score (IPSS) of ≥7, prostate volume of ≥30 ml, documented BOO confirmed through Pressure-Flow studies (PFS) and were deemed suitable candidates for transurethral prostatectomy (TURP). Exclusion criteria encompassed neurological disorders, prior lower urinary tract interventions, presence of prostate cancer in TURP specimens, bladder stones, and indwelling catheterization exceeding three months. All participants underwent PFS analysis at baseline and in the third postoperative month, adhering to the standards delineated by the International Continence Society. Based on the presence or absence of DO at baseline, participants were categorized into two groups: Group A comprised individuals exhibiting DO, while Group B comprised those without DO. The degree of inflammation in TURP biopsy specimens was evaluated using the Irani score. The primary endpoint centered on disparities in PI, while secondary endpoints included the extent of PI, postoperative changes in DO, and alterations in prostate-specific antigen (PSA) levels.

A total of 127 individuals met the eligibility criteria, of whom 125 successfully completed the study. At baseline, 58.4% (73/125) of participants were classified into Group A, while the remaining 41.6% (52/125) were allocated to Group B. Overall, PI was discerned in 78.4% (98/125) of participants: 84.9% (62/73) in Group A and 69.2% (36/52) in Group B (p= 0.02). The relative risk of concurrent DO and PI was calculated as 2.824. Among those afflicted with PI, 22.6% (14/62) exhibited mild inflammation, 45.1% (28/62) manifested moderate inflammation, and 32.3% (20/62) presented severe inflammation. In Group B, 44.4% (16/36) evidenced mild inflammation, 38.9% (14/36) displayed moderate inflammation, and 16.7% (6/36) showcased severe inflammation. Postoperatively, DO resolution was observed in 75.3% (55/73) of participants; however, all 18 individuals with persistent DO post-surgery evinced evidence of moderate (33.3%) and severe (66.7%) inflammation. The relative risk of persistent DO in individuals with more pronounced PI subsequent to TURP was determined to be 1.371. Regarding TURP, the median volume of resected prostate tissue measured 35cc3, with a mean PSA reduction of 65%.

The findings of this study shed light on the intricate relationship between detrusor overactivity (DO) and prostatic inflammation (PI) in patients with bladder outlet obstruction (BOO) secondary to benign prostatic hyperplasia (BPH). Notably, a significant proportion of participants exhibited PI, with 78.4% of individuals displaying inflammatory changes in prostate tissue. This observation underscores the frequent association between BPH and underlying inflammatory processes within the prostate gland.
Furthermore, the analysis revealed a noteworthy correlation between the presence of DO and the occurrence of PI. Specifically, individuals with DO were more likely to exhibit PI compared to those without DO, with a relative risk of 2.824. This finding suggests a potential link between neuromuscular disturbances in the bladder wall, characteristic of DO, and the inflammatory processes occurring within the prostate gland.
The severity of PI was also evaluated, with a substantial proportion of participants demonstrating moderate to severe inflammation. Interestingly, postoperative assessment revealed that individuals with persistent DO after transurethral prostatectomy (TURP) exhibited evidence of moderate to severe inflammation. This suggests that the severity of PI may influence the persistence of DO following surgical intervention, highlighting the importance of addressing inflammatory processes in the management of BPH-related BOO.
Additionally, the reduction in prostate-specific antigen (PSA) levels following TURP indicates the efficacy of surgical intervention in alleviating obstructive symptoms and reducing prostatic tissue volume. The median volume of resected prostate tissue further supports the effectiveness of TURP in addressing BOO secondary to BPH.
Overall, these findings contribute to our understanding of the pathophysiology of BPH-related BOO and underscore the importance of considering both DO and PI in the management of this condition. Further research is warranted to elucidate the underlying mechanisms linking these phenomena and to explore potential therapeutic strategies targeting inflammation in BPH.

In summary, our study reveals a significant correlation between detrusor overactivity (DO) and prostatic inflammation (PI) in patients with benign prostatic hyperplasia (BPH) and bladder outlet obstruction (BOO). We found a higher prevalence of PI in individuals exhibiting DO, suggesting a potential link between bladder wall neuromuscular disturbances and prostatic inflammation. The severity of PI appears to impact the persistence of DO post-transurethral prostatectomy (TURP), emphasizing the importance of addressing inflammation in BPH management. These findings underscore the significance of considering both DO and PI in clinical decision-making for BPH-related BOO and call for further research to explore targeted inflammatory therapies.

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Continence 12S (2024) 101402
DOI: 10.1016/j.cont.2024.101402