The AUA score was subgrouped into obstructive and irritative scores. The obstructive symptom scores in men 2. Similarly, the irritative scores in the men 4. It is conceivable that the pathophysiology of LUTS in men and women is different. Nevertheless, the observation that the prevalence of LUTS characteristic of clinical BPH is equivalent in men and women suggests that important nonprostatic mechanisms likely exist for the development of symptoms.
One of the life-threatening consequences of BPH is the development of urinary retention. Although prostate volume does not appear to be an important predictor of LUTS severity, there is increasing evidence that the risk of developing urinary retention is related to prostate size. There is only a weak relationship between LUTS and bladder outlet obstruction. Therefore, factors other than prostatic enlargement and bladder outlet obstruction must contribute to the development and severity of LUTS.
Schwartz and Lepor have also demonstrated that in men with clinically localized prostate cancer and LUTS, radical prostatectomy has the same beneficial effect on symptoms as does TURP. The most appropriate study design to elucidate the pathophysiology of clinical BPH would be a comparison of biochemical and histological properties in tissue specimens derived from age-matched men with and without clinical BPH. Ideally, the specimens would be derived from men with prostates of equivalent size.
Several investigators have made comparisons between tissue specimens derived from the inner transition zone and outer peripheral zone regions of the prostate. In the enlarged prostate, the outer and inner zones correspond to the surgical capsule and the hyperplastic tissue, respectively. These comparisons do not provide insight into the pathophysiology of clinical BPH but instead compare regional differences in the prostate. Preoperatively, symptom scores, peak flow rate, and prostate volumes were routinely measured.
In our studies, the stromal:epithelial ratio was greater in men with symptomatic BPH, suggesting that the cellular composition of the inner gland transition zone may represent an important factor contributing to the pathophysiology of clinical BPH Table 4. Spitsbergen and coworkers 23 have reported that the frequency of micturition in the spontaneous hypertensive rat SHR is greater than in controls, implying that the increased levels of norepinephrine may mediate voiding dysfunction.
Lepor and colleagues 24 reported an inverse relationship between the AUA symptom score and catecholamine level in consecutive men undergoing prostatic biopsy for an elevated prostate-specifc antigen PSA or abnormal digital rectal examination who had no evidence of prostate cancer. This observation strongly suggests that the pathophysiology of clinical BPH is not due to increased adrenergic innervation.
In summary, the studies from our laboratory identified the cellular composition of the prostate as the only parameter contributing to the pathophysiology of clinical BPH.
The pairwise relationships between baseline peak flow rate and percent smooth muscle, baseline total symptom score and percent smooth muscle, percent change in peak flow rate and percent smooth muscle, and percent change in the symptom score and percent smooth muscle are shown in Table 5. These pairwise relationships demonstrate a statistically and clinically significant relationship between the baseline peak flow rate and the percent smooth muscle, and no significant relationship between the baseline total symptom score and percent smooth muscle.
These observations suggest that the amount of prostate smooth muscle contributes to bladder outlet obstruction and not to symptomatology. These observations provide further evidence that LUTS and bladder outlet obstruction are not causally related. The relationship between the increase in peak flow rate and the percent smooth muscle was highly significant, suggesting that the improvement in bladder outlet obstruction secondary to terazosin is related to relaxation of prostatic smooth muscle.
A very weak and statistically insignificant relationship was observed between the percent change in the total symptom score and the percent smooth muscle, suggesting that the symptom improvement associated with terazosin is most likely not mediated via relaxation of prostate smooth muscle.
If the pathophysiology of LUTS is due to bladder outlet obstruction resulting from enlargement of the prostate, then the improvement in symptom scores in men undergoing treatment for BPH should be directly proportional to the increase in peak flow rates and the decrease in prostate volume.
The overwhelming clinical evidence derived from both surgical and medical therapy databases provides evidence suggesting that decreases in symptom scores are not proportional to increases in peak flow rate or reduction of prostate volume. Schaeffer has reported that symptom improvement following prostatectomy is equivalent in men with and without pressure flow evidence of bladder outlet obstruction.
Over the entire 52 weeks of the randomized study, changes in peak flow rate and AUA symptom score were not significantly different between placebo and finasteride. The changes in peak flow rate and AUA symptom score between placebo and terazosin were highly statistically significant, whereas this relationship between terazosin and combination therapy was not statistically or clinically significant.
The equivalent effectiveness of placebo versus finasteride and terazosin versus combination therapy is compelling evidence that finasteride has an extremely limited role in the medical management of BPH. A subset analysis of the VA study demonstrated a small difference between the changes in peak flow rates and AUA symptom scores in men receiving finasteride versus placebo in those men with large prostates.
The proposed mechanism of action for the efficacy of finasteride in men with BPH is reduction of prostate volume. Table 6 shows the P and r 2 values for the pairwise relationship between changes in prostate volume and changes in peak flow rate, as well as the relationship between changes in prostate volume and changes in AUA symptom score for the subjects randomized to the finasteride group in the VA study.
The mechanism for the minimal efficacy associated with finasteride is not related to reduction of prostate volume.
If the mechanism for the improvement in symptomatology is related to alleviating bladder outlet obstruction, then a significant relationship should exist between changes in AUA symptom score and changes in the peak flow rate. A significant relationship was observed between changes in AUA symptom score and peak flow rate, only in the finasteride and combination groups Table 7. There is no reasonable explanation as to why there exists a relationship between changes in AUA symptom scores and changes in peak flow rates for the combination and not the terazosin group.
If the symptom improvement following terazosin administration is not related to the baseline peak flow rate, then excluding men with LUTS and no evidence of bladder outlet obstruction may not be justified. A subset analysis of the VA study examined the symptom improvement according to baseline peak flow rate quartile groups. Lepor and colleagues 29 have recently reported that symptom improvements in age-matched men with prostate volumes of equivalent size were equivalent in men with normal and abnormal baseline peak flow rates.
In summary, reduction of prostate volume at best accounts for only a small portion of finasteride's minimal effect on LUTS. The more severe manifestations of BPH include urinary retention, urinary tract infection, and renal insufficiency. There is increasing evidence that men with larger prostates are at greater risk of developing urinary retention. Translate PDF. Volume 14, Issue 2 Ver. III Feb. Ram Ratan1, Dr. Shivcharan Navariya2, Dr.
Ajay Malviya3, Dr. Madan K4, Dr. Pankaj Porwal5, Dr. Saxena6 1 Assistant Prof. Department Of Gen Surgery, Dr. There Were Male LUTS can be classified into three categories, ie, voiding or obstructive hesitancy, slow stream, intermittency ,incomplete emptying , storage or irritative frequency, urgency, nocturia, urge urinary incontinence and postmicturition postvoid dribbling [1].
These conditions have a significant impact on overall quality of life. The pathogenesis of BPH is still not well understood, but involves several complicated pathways, including inflammation, apoptosis, and cellular proliferation. Going beyond the guidelines in the field, this title enhances the knowledge of BPH onset, allowing for the advancement of research, beneficial clinical implication and treatment.
Perfect for researchers, urologists, pathologists and endocrinologists, this must-have reference provides what is needed to understand LUTS and BPH in one easy to reference place. A number of factors have led to this discussion. In an increasing proportion of aging men, for example, BPH causes so-called obstructive symptoms that must be relieved by medical or operative means.
This entails an immense social and economic impact in terms of health costs. In addition, recent data indicate the most frequently performed operation for BPH - transurethral resection of the prostate - is associated with a higher risk of death due to cardiac disease than open prostatectomy. This means that these patients do not receive the most effective therapy. Finally, various new treatment been developed, including medical treat modalities have ment directed at endocrine pathways in the prostatic cells, balloon dilatation, spirals, temporary or permanent stents, C.
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