Update on overactive bladder: Pharmacologic approaches on the horizon

Practical management of nocturia in urology

Until last decades, nocturia has been considered as an irritative symptom of benign prostatic hyperplasia (BPH), but the nocturia is unresponsive symptoms to various modalities of BPH treatment. More recently, it has been recognized that the prostate is not so quite important as previously believed, as nocturia is equally common in women. The understanding of nocturia has been much changed in last decade; it is a highly prevalent condition, and symptoms in men and women are really no different either quantitatively or qualitatively. The successful introduction of desmopressin (l-deamino-8-D-arginine vasopressin, DDAVP) to decrease nocturnal urine output in severe nocturia which resistant to conventional BPH treatment and in women demonstrated new perspectives in management of nocturia. We reviewed the definition and etiologies of nocturia, offering the current diagnostic procedures and standards of care.

Nocturia in relation to sleep, health, and medical treatment in the elderly

Nocturia is a common condition in the elderly that profoundly influences general health and quality of life. It appears to predict a higher risk of death. One consequence of nocturia is sleep deterioration, with increased daytime sleepiness and loss of energy and activity. Accidents, e.g. falls, are increased both at night and during the day in elderly persons with nocturia. Nocturia is caused by nocturnal polyuria, reduced voided volumes, or a combination of the two. Nocturnal polyuria can be caused by numerous diseases, e.g. diabetes insipidus, diabetes mellitus, congestive heart failure, and sleep apnoea. A disorder of the vasopressin system, with very low or undetectable vasopressin levels at night, is manifested as an increased nocturnal urine output, which in the most extreme cases reaches 85% of the 24-h diuresis: the prevalence of low or undetectable vasopressin levels at night has been estimated to be 3-4% in those aged >or= 65 years. Treatment of nocturia may include avoiding excessive fluid intake and use of diuretic medication in the afternoon rather than the morning, oral desmopressin at bedtime in cases of nocturnal polyuria, and antimuscarinic agents in the case of overactive bladder or impaired storage capacity of the bladder.

Botulinum-A toxin detrusor and sphincter injection in treatment of overactive bladder syndrome: objective outcome and patient satisfaction

OBJECTIVE

We investigated the effect of botulinum-a toxin injections into the detrusor and external sphincter muscle in patients with overactive bladder (OAB) symptoms.

METHODS

We included 44 patients - 41 women and three men with a mean age of 66.1 years - who were suffering from OAB symptoms that were refractory to anticholinergic treatment. We injected 200-300 U of BTX-A (Botox) into the detrusor muscle; 22 patients also received external sphincter injections. For outcome analysis, we used a bladder diary, a urodynamic examination, and a questionnaire that consisted of 27 validated questions.

RESULTS

Changes in the bladder diary 4 weeks and 3, 6, and 9 months after BTX-A injection were as follows: Micturition frequency was reduced by 12%, 16%, 13% and 9%, respectively. Average pad use decreased from 4.2 pads per day to at most 2.4 pads per day after 6 months. Urodynamic changes were most distinct after 4 weeks: the volume when the first uninhibited detrusor contraction occurred increased from 149+/-18.2 mL to 263 +/- 24.2 mL, and maximum cystometric bladder capacity increased from 228 +/- 19.2 mL to 305 +/- 19.0 mL. Subjectively, 86% of the patients would choose this procedure for their bladder condition again. Residua 4 weeks after additional injection into the sphincter muscle were distinctly smaller than in the "only detrusor" group.

CONCLUSIONS

BTX-A detrusor and sphincter injection is very effective in treating OAB symptoms. For patients who might be expected to have residual urine after injection only into the detrusor, additional injection of low doses of BTX-A into the external sphincter muscle could be one option to reduce that risk.

Preview of new drugs for overactive bladder and incontinence: darifenacin, solifenacin, trospium, and duloxetine

This year, the US Food and Drug Administration will approve four new drugs indicated for the treatment of lower urinary tract dysfunction. Darifenacin, solifenacin, and trospium are antimuscarinic agents aimed at relieving the symptoms of overactive bladder and urge incontinence in men and women. Duloxetine will be the first drug approved for the treatment of female stress urinary incontinence. This article presents current data on the efficacy and tolerability of these new agents and invites the reader to decide whether they offer any potential advantages over existing therapies.

Antimuscarinic agents: Implications and concerns in themanagement of overactive bladder in the elderly

BACKGROUND

Overactive bladder (OAB) is a widespread problem that has a negative effect on quality of life, particularly among the elderly. Antimuscarinic agents are the only drug class with broad, accepted efficacy in the treatment of OAB. Their clinical usefulness, however, is limited by dose-dependent adverse effects. In the elderly, the most serious of these is central nervous system (CNS) dysfunction, including cognitive impairment.

OBJECTIVE

This article examines currently available antimuscarinic agents for the treatment of OAB in terms of their likelihood of causing CNS dysfunction by crossing the blood-brain barrier (BBB) and blocking muscarinic type 1 (Ml) receptor sites in the brain.

METHODS

Pertinent studies were selected from a comprehensive review of the OAB literature with a focus on muscarinic receptor-associated mechanisms leading to CNS adverse effects and their potential impact on elderly patients. MEDLINE was searched for articles published in the past 10 years, and additional articles were obtained from the reference lists of identified publications. Also searched were abstracts of recent meetings of the International Consultation on Incontinence, International Continence Society, American Urological Association, and European Association of Urology.

RESULTS

Antimuscarinic agents control involuntary detrusor muscle contractions through cholinergic blockade at the muscarinic receptors. The prevalence of OAB is highest in the elderly, the population most likely to be taking multiple anticholinergic medications and most vulnerable to the CNS adverse effects of these agents. Nonselective antimuscarinic agents that bind to the Ml receptor are most likely to cause significant cognitive adverse effects compared with the more selective antimuscarinic agents for the treatment of OAB.

CONCLUSIONS

When considering use of an antimuscarinic agent for the treatment of OAB in elderly patients, prescribers should routinely consider the agent's receptor selectivity and ability to cross the BBB. The medical history should include all current medications that may contribute to the anticholinergic burden and cognitive impairment. Patients and caregivers should be educated to recognize anticholinergic adverse effects.