Beneficial influence of carvedilol on urologic indices in patients with hypertension and benign prostatic hyperplasia: results of a randomized, crossover study

Effects of carvedilol on human prostate tissue contractility and stromal cell growth pointing to potential clinical implications

BACKGROUND

Apart from antagonizing ß-adrenoceptors, carvedilol antagonizes vascular α1-adrenoceptors and activates G protein-independent signaling. Even though it is a commonly used antihypertensive and α1-adrenoceptors are essential for the treatment of voiding symptoms in benign prostatic hyperplasia, its actions in the human prostate are still unknown. Here, we examined carvedilol effects on contractions of human prostate tissues, and on stromal cell growth.

METHODS

Contractions of prostate tissues from radical prostatectomy were induced by electric field stimulation (EFS) or α1-agonists. Growth-related functions were examined in cultured stromal cells.

RESULTS

Concentration-response curves for phenylephrine, methoxamine and noradrenaline were right shifted by carvedilol (0.1-10 µM), around half a magnitude with 100 nM, half to one magnitude with 1 µM, and two magnitudes with 10 µM. Right shifts were reflected by increased EC50 values for agonists, with unchanged Emax values. EFS-induced contractions were reduced by 21-54% with 0.01-1 µM carvedilol, and by 94% by 10 µM. Colony numbers of stromal cells were increased by 500 nM, but reduced by 1-10 µM carvedilol, while all concentrations reduced colony size. Decreases in viability were time-dependent with 0.1-0.3 µM, but complete with 10 µM. Proliferation was slightly increased by 0.1-0.5 µM, but reduced with 1-10 µM.

CONCLUSIONS

Carvedilol antagonizes α1-adrenoceptors in the human prostate, starting with concentrations in ranges of known plasma levels. In vitro, effect sizes resemble those of α1-blockers used for the treatment of voiding symptoms, which requires concentrations beyond plasma levels. Bidirectional and dynamic effects on the growth of stromal cells may be attributed to "biased agonism".

Effects of the beta-blocker carvedilol on arrhythmia and long-term clinical outcomes in benign prostate hypertrophy patients

Benign prostatic hypertrophy (BPH) is associated with autonomic dysfunction and sympathetic nervous system mediated by the alpha receptor. However, limited data exist regarding the effects of the beta-blocker (BB) carvedilol on arrhythmia and urologic outcomes in BPH patients. Our database of patients diagnosed with BPH from 2015 to 2020 was used to obtain echocardiography and electrocardiogram data. Inclusion criteria were BPH patients taking BBs. International Prostate Symptom Score questionnaire were used to evaluate the urinary symptoms and quality of life. Among 448 patients with BPH (69.2 ± 10.9 years) taking BBs, 219 patients took carvedilol (48.9%) and 229 patients took a non-carvedilol BB (51.1%; bisoprolol, 184 patients, 80% or nebivolol, 45 patients, 20%). Difference in the baseline characteristics was not observed. During the median 36-month follow-up, a lower incidence of arrhythmic events (P = .029), total urologic events (P < .001), and less use of additive alpha-blocker was observed in the carvedilol group (P = .022). In multivariate analysis, less carvedilol use (P = .019), heart failure (P < .001), stroke (P < .001), and cardiomyopathy (P = .046) were independent risk factors for arrhythmic events. In addition, less carvedilol use (P = .009) and older age (P = .005) were independent risk factors for urologic events based on BB type at the median 36-month follow-up. The use of carvedilol was associated with less arrhythmic events in BPH patients with palpitation and decreased the incidence of urologic events in BPH compared with the use of non-carvedilol BBs in long-term follow-up.

Association of Overactive Bladder With Hypertension and Blood Pressure Control: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

The sudden urge to urinate, also known as overactive bladder (OAB), may reflect higher sympathetic activity and associate with higher blood pressure (BP).

METHODS

This cross-sectional analysis utilized data from sixth follow-up exam (2015-2016) of Multi-Ethnic Study of Atherosclerosis to examine the association of OAB with systolic (SBP) and diastolic blood pressure (DBP) levels, hypertension, and BP control. Information on urinary symptoms was obtained with the International Consultation on Incontinence Questionnaire (ICIQ). Sex-stratified regression models were constructed to examine differences in BP, hypertension prevalence, and BP control while adjusting for demographic factors, comorbidities, and medication use.

RESULTS

Among the 1,446 men and 1,628 women who completed the ICIQ (mean age 73.7 years [SD 8.4]), OAB was present in 31.6% of men and 38.9% of women. With no antihypertensive medication use, OAB was not associated with SBP or DBP in both men and women after adjusting for covariates. However, among the 894 men and 981 women on antihypertensive medication, OAB was associated with higher SBP among men (4.04 mm Hg; 95% confidence interval [CI] 1.02, 7.06) but not among women (-0.67 mm Hg; 95% CI -3.79, 2.46) while DBP did not differ by OAB presence in men or women. In addition, OAB was also associated with lower odds of BP control among men (odds ratio [OR] 0.69; 95% CI 0.49, 0.96) but not women (OR 0.96; 95% CI 0.71, 1.30).

CONCLUSIONS

Among men, OAB is associated with lower odds of BP control which suggests that OAB may impede hypertension management.

Overactive Bladder is a Distress Symptom in Heart Failure

The prevalence of Heart failure (HF) is expected to increase worldwide with the aging population trend. The numerous symptoms of and repeated hospitalizations for HF negatively affect the patient’s quality of life and increase the patient’s economic burden. Up to 50% of patients with HF suffer from urinary incontinence (UI) and an overactive bladder (OAB). However, there are limited data about the relationship between UI, OAB, and HF. The association between HF and urinary symptoms may be directly attributable to worsening HF pathophysiology. A comprehensive literature review was conducted for all publications between January 2000 and November 2017 using the PubMed, Embase, and Cochrane databases. HF represents a major and growing public health problem, with an increased risk of UI and an OAB as comorbidities. Possible effects of HF on urinary problems may be mediated by the prescription of medications for symptomatic relief. Although diuretics are typically used to relieve congestion, and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers improve survival, these classes of drugs have been suggested to worsen urinary symptoms in the presence of HF. Further research is required to understand the impact of UI and an OAB on the HF illness trajectory.

Effect of Silodosin, an Alpha1A-Adrenoceptor Antagonist, on Ventral Prostatic Hyperplasia in the Spontaneously Hypertensive Rat

Background

A decreased prostatic blood flow could be one of the risk factors for benign prostatic hyperplasia/benign prostatic enlargement. The spontaneously hypertensive rat (SHR) shows a chronic prostatic ischemia and hyperplastic morphological abnormalities in the ventral prostate. The effect of silodosin, a selective alpha_1A-adrenoceptor antagonist, was investigated in the SHR prostate as a prostatic hyperplasia model focusing on prostatic blood flow.

Methods

Twelve-week-old male SHRs were administered perorally with silodosin (100 μg/kg/day) or vehicle once daily for 6 weeks. Wistar Kyoto (WKY) rats were used as normotensive controls and were treated with the vehicle. The effect of silodosin on blood pressure and prostatic blood flow were estimated and then the prostates were removed and weighed. The tissue levels of malondialdehyde (MDA), interleukin-6 (IL-6), chemokine (C-X-C motif) ligand 1/cytokine-induced neutrophil chemoattractant 1 (CXCL1/CINC1), tumor necrosis factor-alpha (TNF-α), transforming growth factor beta 1 (TGF-β1), basic fibroblast growth factor (bFGF) and alpha-smooth muscle actin (α-SMA) were measured. The histological evaluation was also performed by hematoxylin and eosin staining.

Results

There was a significant increase in blood pressure, prostate weight, prostate body weight ratio (PBR), tissue levels of MDA, IL-6, CXCL1/CINC1, TNF-α, TGF-β1, bFGF and α-SMA in the SHR compared to the WKY rat. The ventral prostate in the SHR showed the morphological abnormalities compared to the WKY rat. Prostatic blood flow was decreased in the SHR. However, treatment with silodosin significantly restored the decreased prostatic blood flow in the SHR. Moreover, silodosin normalized tissue levels of MDA, IL-6, CXCL1/CINC1, TNF-α, TGF-β1, bFGF and α-SMA, and it ameliorated ventral prostatic hyperplasia in the SHR excluding blood pressure. Silodosin decreased PBR but not prostate weight in the SHR.

Conclusions

Silodosin can inhibit the progression of prostatic hyperplasia through a recovery of prostatic blood flow.

Managing therapeutic competition in patients with heart failure, lower urinary tract symptoms and incontinence

Up to 50 % of heart failure patients suffer from lower urinary tract symptoms. Urinary incontinence has been associated with worse functional status in patients with heart failure, occurring three times more frequently in patients with New York Heart Association Class III and IV symptoms compared with those with milder disease. The association between heart failure and urinary symptoms may be directly attributable to worsening heart failure pathophysiology; however, medications used to treat heart failure may also indirectly provoke or exacerbate urinary symptoms. This type of drug–disease interaction, in which the treatment for heart failure precipitates incontinence, and removal of medications to relieve incontinence worsens heart failure, can be termed therapeutic competition. The mechanisms by which heart failure medication such as diuretics, angiotensin-converting enzyme (ACE) inhibitors and β-blockers aggravate lower urinary tract symptoms are discussed. Initiation of a prescribing cascade, whereby antimuscarinic agents or β3-agonists are added to treat symptoms of urinary urgency and incontinence, is best avoided. Recommendations and practical tips are provided that outline more judicious management of heart failure patients with lower urinary tract symptoms. Compelling strategies to improve urinary outcomes include titrating diuretics, switching ACE inhibitors, treating lower urinary tract infections, appropriate fluid management, daily weighing, and uptake of pelvic floor muscle exercises.