BPH is highly prevalent and can progress over time, but not all patients with BPH have the similar risk for progression [29,30]. Figuring out factors of this risk has been an ongoing process over the past decades. A few trials have investigated to elucidate patients’ characteristics that portend worse prognoses [10–12]. But these trials mainly focused on the demographic and clinical factors, like age, BMI, PSA, PV, PVR, Qmax, LUTS severity, etc., and very rarely mentioned about the influences of prostatic morphology. Consequently, in order to elucidate the correlation of prostatic morphological parameters and BPH clinical progression, this research was conducted.
The main findings of our study are that: PV, TZV, TZI and IPP are all positively associated with BPH progression. Patients with lager prostatic measurements are more easily to clinically progress. Reasonable and seasonable management should be considered for patients with PV 60 mL, TZV 15 mL, TZI 0.5 or IPP 5 mm, before clinical progression occurs.
Clinical progression of BPH is mainly referred as LUTS getting severer and serious complications such as hematuria, recurrent UTI, bladder stones, bladder diverticulum, AUR, and even renal insufficiency and failure occurring [6]. The trial of Medical Therapy of Prostatic Symptoms (MTOPS) used the definition of disease progression as the first occurrence of an increase over baseline of at least 4 points in the American Urological Association (AUA) Symptom Score, AUR, urinary incontinence, renal insufficiency or recurrent UTI [6]. However, since not all of the clinical centers are capable of routinely assessing renal function, or the AUA Symptom Score in a primary care setting for BPH patients, and sometimes it’s even hard to distinguish the pathogenesis of recurrent UTI and urinary incontinence, we attempted to make our work more broadly applicable by creating a simplified BPH clinical progression model with easily and routinely measured clinical and radiographic factors (hydronephrosis, bladder stone, AUR, bladder diverticulum). We defined BPH clinical progression as the occurrence of any of the BPH related complications mentioned above. Sarma et al. reported that disease progression occurred in 14 % of the BPH patients left untreated over a follow-up period of 5 years[24]. Guo et al. investigated 2271 BPH patients and found 1078 (47.5 %) had BPH-related complications [25]. However, when we used the simplified BPH clinical progression model, the cumulative incidence of disease progression was much higher (63.68 %). But intriguingly, this result was in accordance with the Chinese habit of delayed doctor visiting until the symptoms become severe. In this study, the mean (SD) age of these first hospital visiting BPH patients was 70.61 (9.11) years, which was much elder than in other countries[26,10], confirming this special phenomenon from the other aspect. But actually, this simplified model need to be validated by further larger-scale and better-designed studies conducted in multicenter before extrapolating the present findings to patients with BPH presenting in real life.
Nocturia is a highly prevalent and easy-to-measure bladder storage symptom, and also one of the most bothersome components in men with LUTS/BPH [17,18]. Frequently voiding twice or more per night can have a substantial impact on an individual’s QoL, with sleep disruption leading to chronic fatigue, increased risk of falls and fractures, as well as mortality [27,28]. Therefore, nocturia is widely used to evaluate the severity of LUTS [29]. In China, it’s unpractical to systemically evaluate LUTS severity of patients in their first outpatient or emergency visiting using PVR, Qmax, IPSS or other index score in most situations because of the unbalance of patient-clinician ration and the inspection related economic burden, especially at primary hospitals. And as an attempt to make our work more broadly applicable by creating a simplified model with easily measured factors, we used nocturnal voiding frequency as the only indicator to represent the severity of LUTS in this study. It was found that 94.70 % (983 /1038) of the patients presented nocturia in our study, and nocturnal voiding frequency showed a significant OR (OR: 1.432, 95% CI: 1.292–1.587, p 0.001) with BPH progression using univariate logistic regression analysis, which meant utilizing nocturia to represent LUTS is partially reasonable, but still needed to be further validated.
5-alpha-reductase inhibitor (5-ARI) is used as the first-line pharmacological therapy for men with moderate-to-severe LUTS, mainly for modifying the natural history of BPH by delaying the disease progression [37,38]. Results of MTOPS showed finasteride could manifest a 34 % risk reduction in overall BPH clinical progression compared to placebo. Treatment of 5-ARI for over 2 years have also been demonstrated to significantly reduce prostatic measurements[30]. Thus, taken together all of these findings with our results that patients with larger prostatic morphological parameters are more easily to progress may be useful to clinicians and patients in deciding on appropriate treatment options.
A potential limitation of this study is that it was a retrospective cross-sectional study conducted in a single institution and the usage of the unverified simplified BPH clinical progression model. This needs to be borne in mind in extrapolating the present findings to patients with BPH presenting in real life, in clinic settings. Consequently, further perspective larger-scale and better-designed studies conducted in multicenter will be expectant.
In a nutshell, prostatic morphological parameters are significantly associated with BPH clinical progression. Patients with larger prostatic morphological parameters are more easily to progress. Utilizing these parameters permits estimation of individual patient risk for clinical progression. Novel clinical decision strategies based on our results will allow urologists to weigh patient-specific benefits against possible risks of adverse effects for a given patient, which will be helpful in developing more cost-effective treatment strategies for BPH management. But our results need to be further validated before extrapolating in clinical application.