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

Radiofrequency as the New Opportunity in Treating Overactive Bladder and Urge Urinary Incontinence-A Single-Arm Pilot Study

Background and Objectives: Until now, overactive bladder (OAB) with or without urge urinary incontinence (UUI) has been treated mainly in two ways: with behavioral methods and patient education, or using antimuscarinic drugs and/or beta-3 adrenergic receptor agonists. Unfortunately, these drugs may cause side effects in some women or are insufficiently effective, so patients abandon them. Therefore, in this pilot study, radiofrequency was evaluated as a new option in the treatment of OAB and UUI. Materials and Methods: Nineteen patients were enrolled in this pilot study using radiofrequency (RF), where the level of OAB and UUI was assessed using the validated ICIQ-OAB questionnaire. RF was applied four times for 20 min, once a week. Two weeks after treatment, the level of OAB and UUI was reassessed and processed statistically and the treatment effect evaluated. Results: Using the ICIQ-OAB, the severity of OAB and UUI was assessed: 0-3 mild symptoms; 4-7 moderate symptoms; 8-11 severe symptoms; 12-16 very severe symptoms. Before treatment, 10.5% of patients had mild symptoms, 21.1% moderate symptoms, 63.2% severe symptoms and 5.3% very severe symptoms. After treatment, 42.9% had mild symptoms, 50% moderate symptoms and 7% severe OAB and UUI symptoms. All four main symptoms-frequency, nocturia, urgency and incontinence-decreased statistically significantly, with the best results being found in urgency (p = 0.002). Conclusions: Based on this pilot study, RF seems a very promising method in the treatment of OAB and UUI. To extend our initial findings, it is necessary to perform a prospective, randomized and placebo-controlled study in order to obtain reliable results and to determine for how long one set of treatment maintains the results obtained immediately after the end of that treatment. In this way, we may determine how often the treatment needs to be repeated, if necessary, and when.

Receipt of Overactive Bladder Drugs and Incident Dementia: A Population-based Case-control Study

BACKGROUND

The differential risk of incident dementia associated with receiving various overactive bladder (OAB) drugs is unknown.

OBJECTIVE

To estimate the association of antimuscarinic OAB drug (exposure), compared with a β-3 agonist (mirabegron), and incident dementia.

DESIGN, SETTING, AND PARTICIPANTS

A population-based nested case-control study was conducted in patients treated with OAB medications in Ontario, Canada. A total of 11 392 patients aged ≥66 yr with a new diagnosis of dementia between 2010 and 2017, and 29 881 age- and sex-matched controls without dementia were included in the study.

INTERVENTION

Receipt of an antimuscarinic OAB drug or receipt of mirabegron, within the previous 6-12 mo.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cases developed dementia and Alzheimer's disease. Controls were derived from the general population and matched to cases based on important baseline characteristics. Odds ratios (ORs) for incident dementia, adjusted for demographic and health-related characteristics, were determined.

RESULTS AND LIMITATIONS

Patients receiving solifenacin (OR 1.24; 95% confidence interval 1.08-1.43) and darifenacin (OR 1.30; 95% CI 1.08-1.56) in the prior 6 mo had increased odds of incident dementia compared with those receiving mirabegron. In the 6 mo to 1 yr prior to diagnosis, receipt of solifenacin (OR 1.34; 95% CI 1.11-1.60), darifenacin (OR 1.49; 95% CI 1.19-1.86), tolterodine (OR 1.21; 95% CI 1.02-1.45), and fesoterodine (OR 1.39; 95% CI 1.14-1.71) was associated with increased odds of incident dementia compared with receipt of mirabegron. No effect was seen with oxybutynin or trospium. Limitations included misclassification of the outcome and residual confounding associated with the use of health administrative databases.

CONCLUSIONS

Older adults receiving solifenacin and darifenacin in the 6 mo prior to diagnosis, and those receiving solifenacin, darifenacin, tolterodine, or fesoterodine in the year prior to diagnosis, have increased odds of incident dementia, compared with those receiving mirabegron. Oxybutynin and trospium were not associated with dementia, likely due to a protopathic bias. Careful drug selection is warranted when treating patients with OAB.

PATIENT SUMMARY

In a large Canadian cohort of patients who developed dementia after starting an overactive bladder (OAB) medication, those taking some anticholinergic medications for OAB have an increased risk of dementia compared with those taking mirabegron.

Neurological safety and efficacy of darifenacin and mirabegron for the treatment of overactive bladder in patients with history of cerebrovascular accident: A prospective study

OBJECTIVES

To evaluate the neurological safety and clinical efficacy of darifenacin and mirabegron in patients with a history of cerebrovascular accident (CVA) who had overactive bladder (OAB) symptoms.

METHODS

This prospective randomized study, approved by the institute's ethics committee, was carried out at a tertiary care center from December 2018 to June 2020. Treatment naïve adult patients with a past history of CVA with stable neurological status for atleast past 3 months with symptoms of OAB for 3 or more months were included. Eligible patients received either darifenacin or mirabegron for a period of 3 months and various parameters on the 3-day International Consultation on Incontinence Questionnaire (ICIQ) bladder diary, the Montreal Cognitive Assessment-Basic score (MoCA-B), and the adverse events at 3 months posttreatment were compared to that at the baseline.

RESULTS

A total of 60 patients were included, 30 in each arm. After 3 months of treatment with darifenacin or mirabegron, the majority of the ICIQ bladder diary parameters improved and there was no deterioration in the cognitive function as noted on the MoCA-B score in either of the arms. On intergroup comparison, the mean change in bladder diary parameters and the MoCA-B scores was similar between the two groups.

CONCLUSION

Darifenacin and mirabegron, in the short term, do not adversely affect the cognitive function in patients with a history of CVA with OAB symptoms. Both are safe and effective treatment options in patients with OAB post-CVA.

Different antimuscarinics when combined with atomoxetine have differential effects on obstructive sleep apnea severity

The combination of the noradrenergic agent atomoxetine plus the antimuscarinic oxybutynin has recently been shown to improve upper airway physiology and reduce obstructive sleep apnea (OSA) severity. However, the effects of different antimuscarinics when combined with atomoxetine is limited. This study aimed to determine the effects of atomoxetine combined with two different antimuscarinics with varying M-subtype receptor selectivity on OSA severity and upper airway physiology. Ten people with predominantly severe OSA completed a double-blind, randomized, placebo-controlled, cross-over trial. Participants completed three overnight in-laboratory sleep studies after either 80 mg atomoxetine + 5 mg solifenacin succinate (ato-sol) or 80 mg atomoxetine + 2 mg biperiden hydrochloride (ato-bip) or placebo. OSA severity, ventilatory stability (loop gain), respiratory-arousal threshold (via epiglottic manometry), next-day subjective sleepiness [Karolinska Sleepiness Scale (KSS)], and alertness were compared between conditions. Neither drug combination altered the apnea/hypopnea index versus placebo (P = 0.63). Ato-sol caused a shift toward milder respiratory events with reduced frequency of obstructive apneas (13 ± 14 vs. 22 ± 17 events/h; means ± SD, P = 0.04) and increased hypopneas during nonrapid eye movement (NREM) (38 ± 21 vs. 24 ± 18 events/h, P = 0.006) with improved nadir oxygenation versus placebo (83 ± 4 vs. 80 ± 8%, P = 0.03). Both combinations reduced loop gain by ∼10% versus placebo; sleep efficiency and arousal threshold were unaltered. Ato-bip reduced next-day sleepiness versus placebo (KSS = 4.3 ± 2.2 vs. 5.6 ± 1.6, P = 0.03). Atomoxetine + biperiden hydrochloride reduces perceived sleepiness, and atomoxetine + solifenacin modestly improves upper airway function in people with OSA but to a lesser extent versus recently published atomoxetine + oxybutynin (broad M-subtype receptor selectivity) findings. These results provide novel mechanistic insight into the role of noradrenergic and antimuscarinic agents on sleep and breathing and are important for pharmacotherapy development for OSA.NEW & NOTEWORTHY In contrast to recent findings of major reductions in OSA severity when atomoxetine is combined with a nonspecific antimuscarinic, oxybutynin (broad M-subtype receptor selectivity), addition of solifenacin succinate (M2 and M3 muscarinic receptor selectivity) or biperiden (M1 muscarinic receptor selectivity) with atomoxetine had modest effects on upper airway function during sleep, which provide mechanistic insight into the role of noradrenergic and antimuscarinic agents on sleep and breathing and are important for pharmacotherapy development for OSA.

Pharmacist's knowledge regarding the management of overactive bladder in elderly women

OBJECTIVE

Anticholinergic drugs are the mainstay treatment of OAB. Anticholinergic load is the cumulative effect of taking anticholinergic medication. Recent evidence suggests that in the elderly this can have a detrimental affect, with the potential to develop dementia. A previous study found that knowledge of anticholinergic load was lacking in our healthcare professionals. The aim of this study was to assess knowledge of pharmacists, who in the UK have the potential where qualified to prescribe as well as dispense.

STUDY DESIGN

A questionnaire was formulated based on the previous study. It was sent out to 418 pharmacists from; a south London hospital trust, a south London clinical commissioning group and United Kingdom Clinical Pharmacists Association.

RESULTS

Seventy-five pharmacists completed the questionnaire. Solifenacin and tolterodine was the most popular drug prescribed in the elderly without dementia, whilst mirabegron was the most popular in the elderly with dementia. One pharmacist suggested using oxybutynin. Sixty-two percent discuss anticholinergic load with the patients, 40 % advice prescribers and 42 % consider anticholinergic load when dispensing the drug. Fifteen percent have had patients report confusion/memory loss. Thirty percent know how to assess anticholinergic load. Only 15 % felt dementia was a concern with anticholinergic drugs. Worryingly, 54 % though mirabegron exerted anticholinergic effects.

CONCLUSION

This is the first study looking at pharmacist knowledge on the use of anticholinergic medication for OAB in elderly women. Knowledge amongst all healthcare professionals including pharmacists is lacking and needs to be improved.

Managing Nocturia in Frail Older Adults

This review discusses the available evidence in the current evaluation and treatment of nocturia in frail older adults. No evidence specifically evaluates the use of behavioral interventions in the treatment of the frail older adult with nocturia, but their use is supported in other cohorts. Behavioral modifications and optimal management of comorbidities remain the first-line treatment for all age groups and should be emphasized in the frail due to their favorable safety profile. No studies specific to the frail older adult support the use of pharmacotherapy. Some evidence exists for the efficacy of several agents in the older adult; however, this is difficult to extrapolate to the frail, and safety concerns abound. Desmopressin may be effective in the older adult, but a high risk of hyponatremia raises concerns for its safety, and therefore it is not recommended in the frail. α-Antagonists may have limited efficacy in men with known benign prostatic hyperplasia (BPH); they are relatively well tolerated, although the risk of orthostatic hypotension in the frail should be considered. β3-agonist trials suggest limited clinical utility. Antimuscarinics are not found to be useful in this cohort and are contraindicated in the frail older adult given the ability of antimuscarinics to cause cognitive impairment, delirium, and falls. No data examine the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in the frail older adult. Additionally, the American Geriatrics Society Beers Criteria recommends against the use of muscarinics in those over the age of 75 years and therefore their use is not supported.

The cognitive safety of antimuscarinics in the treatment of overactive bladder

INTRODUCTION

Overactive bladder is a common problem women suffer from, with its incidence increasing with age. The mainstay of treatment is antimuscarinic medication. There is growing evidence that antimuscarinics may increase the risk of cognitive impairment, dementia, and even death.

AREAS COVERED

This review explores the evidence that antimuscarinics increase the risk of cognitive impairment, dementia, and death. It evaluates how best to treat overactive bladder the older woman.

EXPERT OPINION

The evidence suggests that antimuscarinics increase the risk of cognitive impairment and dementia in the older adult. Care should be taken to use an antimuscarinic that is less likely to cross the blood-brain barrier and thus reduce the risk of these significant adverse events. A patient's anticholinergic load also needs to be considered when treating this group. Other treatment options such as fluid management, bladder retraining, vaginal estrogens, mirabegron, Onabotulinum toxin A and neuromodulation can be used instead.

Cognitive Effects of Anticholinergic Load in Women with Overactive Bladder

Overactive bladder syndrome (OAB) is defined as urinary urgency, usually accompanied by frequency and nocturia, with or without urgency incontinence, in the absence of urinary tract infection or other obvious pathology. The mainstay of treatment of OAB is anticholinergic/antimuscarinic medication. These drugs block muscarinic receptors throughout the body, not only the bladder, including in the brain, which may lead to cognitive side effects. Anticholinergic load or burden is the cumulative effect of taking drugs that are capable of producing anticholinergic adverse effects. The elderly are more susceptible to these effects, especially as there is increased permeability of the blood brain barrier. The anticholinergic drugs for OAB are able to enter the central nervous system and lead to central side effects. There is increasing evidence that a high anticholinergic load is linked to the development of cognitive impairment and even dementia. Some studies have found an increased risk of mortality. In view of this, care is needed when treating OAB in the elderly. Trospium chloride is a quaternary amine anticholinergic, which has a molecular structure, which theoretically means it is less likely to cross the blood brain barrier and exert central side effects. Alternatively, mirabegron can be used, which is a beta-3 adrenoceptor agonist, which does not add to the anticholinergic load or exert central nervous system side effects. Conservative therapy can be used as an alternative to pharmacological treatment in the form of behavioral modification, fluid management and bladder retraining. Neuromodulation or the use of botox can also be alternatives, but success may be less in the older adult and will require increased hospital attendances.

Cumulative use of therapeutic bladder anticholinergics and the risk of dementia in patients with lower urinary tract symptoms: a nationwide 12-year cohort study

Background

Studies have shown an association between lower urinary tract symptoms (LUTS) and an increased risk of dementia. Whether anticholinergic use contributes to the development of dementia in patients with LUTS remains unknown, especially in Asian populations. This study aims to investigate the association between anticholinergic use and dementia in patients with LUTS.

Methods

This study included patients aged 50 years and over with newly diagnosed LUTS (January 2001 to December 2005), divided into four groups according to their cumulative defined daily doses (cDDDs) of anticholinergics: < 28 cDDDs, 28–84 cDDDs, 85–336 cDDDs, ≥337 cDDDs. Patients were followed up until dementia developed or until the end of 2012.

Results

We recruited a total of 16,412 patients. The incidence of dementia was 10% in the < 28 cDDD group, 8.9% in the 28–84 cDDD group, 11.5% in the 85–336 cDDD group, and 14.4% in the ≥337 cDDD group (p = .005). In a Cox proportional hazards analysis, the adjusted hazard ratio of dementia was 1.15 (95% CI = 0.97–1.37) in the 85–336 cDDD group, and 1.40 (95% CI = 1.12–1.75) in the ≥337 cDDD group after adjusting for covariates.

Conclusions

Our study indicates that higher cumulative anticholinergic exposure is associated with an increase in the risk of incident dementia in patients with LUTS aged 50 years of age and over. Either using one anticholinergic agent or switching anticholinergic agents cumulatively increases this risk. Therapeutic risks and benefits of using anticholinergics in LUTS treatment should be clinically reviewed and weighed.

Cognitive changes in women starting anticholinergic medications for overactive bladder: a prospective study

INTRODUCTION AND HYPOTHESIS

To assess cognitive changes in women 12 months after starting anticholinergic medications for overactive bladder syndrome (OAB).

METHODS

We present a prospective cohort study assessing changes in cognition in women seen in a referral urogynecology practice. We compared women who started anticholinergic OAB medications with women not on anticholinergic OAB medications. The primary outcome was change over time on the Montreal Cognitive Assessment (MOCA) screening score. At enrollment, women completed a baseline MOCA screening, a Geriatric Depression Screen (GDS), and an assessment of medications to create an anticholinergic burden score (ACB). At 3, 6, 9, and 12 months after enrollment women were administered the MOCA, GDS, and a review of their medications and medical problems. Statistical analysis was performed using a linear mixed effects model taking into account correlated error terms given multiple MOCA assessments at various time points per patient.

RESULTS

A total of 106 women were enrolled, 60 in the OAB medication group and 46 in the control (non-OAB medication) group. The mean age was 77 years, 93% of women were Caucasian, and 98% completed high school, with no difference between groups. Over time there was no difference in change of MOCA score between the OAB and control groups when controlling for age, GDS score, and ACB score (p = 0.78). This association did not change when women with a neurological diagnosis were excluded (n = 6). On average MOCA scores for the OAB group increased by 0.76 over 12 months and the control group increased 0.39, with no difference between the groups (p = 0.53).

CONCLUSIONS

We found no changes in MOCA scores between OAB medication and control groups after controlling for age, depression, and polypharmacy after 12 months of follow-up.

Differential Prescribing of Antimuscarinic Agents in Older Adults with Cognitive Impairment

BACKGROUND

Oral oxybutynin has been associated with the development of cognitive impairment.

OBJECTIVE

The objective of this study was to describe the use of oral oxybutynin versus other antimuscarinics (e.g., tolterodine, darifenacin, solifenacin, trospium, fesoterodine, transdermal oxybutynin) in older adults with documented cognitive impairment.

METHODS

This is a population-based retrospective analysis of antimuscarinic new users aged ≥ 66 years from January 2008 to December 2011 (n = 42,886) using a 5% random sample of Medicare claims linked with Part D data. Cognitive impairment was defined as a diagnosis of mild cognitive impairment, dementia, use of antidementia medication, and memory loss/drug-induced cognitive conditions in the year prior to the initial antimuscarinic claim. We used multivariable generalized linear models to assess indicators of cognitive impairment associated with initiation of oral oxybutynin versus other antimuscarinics after adjusting for comorbid conditions.

RESULTS

In total, 33% received oral oxybutynin as initial therapy. Cognitive impairment was documented in 10,259 (23.9%) patients prior to antimuscarinic therapy. Patients with cognitive impairment were 5% more likely to initiate another antimuscarinic versus oral oxybutynin (relative risk [RR] 1.05; 95% confidence interval [CI] 1.03-1.06). The proportion of patients with cognitive impairment initiated on oral oxybutynin increased from 24.1% in 2008 to 41.1% in 2011. The total cost of oral oxybutynin, in $US, year 2011 values, decreased by 10.5%, whereas the total cost of other antimuscarinics increased by 50.3% from 2008 to 2011.

CONCLUSION

Our findings suggest opportunities for quality improvement of antimuscarinic prescribing in older adults, but this may be hampered by cost and formulary restrictions.

Basic and clinical aspects of antimuscarinic agents used to treat overactive bladder

Antimuscarinic agents are now widely used as the pharmacological therapy for overactive bladder (OAB) because neuronal (parasympathetic nerve) and non-neuronal acetylcholine play a significant role for the bladder function. In this review, we will highlight basic and clinical aspects of eight antimuscarinic agents (oxybutynin, propiverine, tolterodine, solifenacin, darifenacin, trospium, imidafenacin, and fesoterodine) clinically used to treat urinary dysfunction in patients with OAB. The basic pharmacological characteristics of these eight antimuscarinic agents include muscarinic receptor subtype selectivity, functional bladder selectivity, and muscarinic receptor binding in the bladder and other tissues. The measurement of drug-receptor binding after oral administration of these agents allows for clearer understanding of bladder selectivity by the integration of pharmacodynamics and pharmacokinetics under in vivo conditions. Their central nervous system (CNS) penetration potentials are also discussed in terms of the feasibility of impairments in memory and cognitive function in elderly patients with OAB. The clinical aspects of efficacy focus on improvements in the daytime urinary frequency, nocturia, bladder capacity, the frequency of urgency, severity of urgency, number of incontinence episodes, OAB symptom score, and quality of life (QOL) score by antimuscarinic agents in patients with OAB. The safety of and adverse events caused by treatments with antimuscarinic agents such as dry mouth, constipation, blurred vision, erythema, fatigue, increased sweating, urinary retention, and CNS adverse events are discussed. A dose-dependent relationship was observed with adverse events, because the risk ratio generally increased with elevations in the drug dose of antimuscarinic agents. Side effect profiles may be additive to or contraindicated by other medications.

Treating Overactive Bladder in Older Patients with a Combination of Mirabegron and Solifenacin: A Prespecified Analysis from the BESIDE Study

BACKGROUND

The BESIDE study demonstrated that combination therapy (mirabegron and solifenacin 5mg) improved overactive bladder symptoms versus solifenacin 5mg or 10mg, and was well tolerated.

OBJECTIVE

To ensure efficacy and safety is maintained in older patients (>65 yr), who usually experience greater symptom severity and comorbidities, a prespecified subanalysis stratified by age group was conducted.

DESIGN, SETTING, AND PARTICIPANTS

Patients remaining incontinent (≥1 episode during 3-d diary) following 4-wk single-blind daily solifenacin 5mg were randomized 1:1:1 to a daily double-blind combination (solifenacin 5mg and mirabegron 25mg, increased to 50mg at wk 4), solifenacin 5mg or 10mg for 12 wk. Four cohorts stratified by age (<65 yr, ≥65 yr and < 75 yr, ≥75 yr) were investigated.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Efficacy assessments: change from baseline to end of treatment in average daily incontinence (primary) and micturition frequency (key secondary), number of incontinence episodes during the 3-d diary (key secondary), and change from baseline in average daily urgency and urgency incontinence episodes. Safety included treatment-emergent adverse events and vital signs.

RESULTS AND LIMITATIONS

Full analysis set included 2110 patients: 30.9% aged ≥65 yr and 8.9% aged ≥75 yr. At the end of treatment, daily, and 3-d incontinence daily micturitions, urgency, and urgency incontinence, were improved in each treatment group and age group; the largest reductions were observed with combination in each age cohort. There were no notable differences in vital signs or the incidence of treatment-emergent adverse events between treatment and age groups, with the exception of dry mouth, which was highest with solifenacin 10mg.

CONCLUSIONS

Efficacy and safety in the overall population is maintained in older (≥65 yr) and elderly (≥75 yr) patients treated with a combination of solifenacin and mirabegron, or solifenacin monotherapy; irrespective of age, combination was associated with the greatest improvement in overactive bladder symptoms.

PATIENT SUMMARY

This study investigated the effectiveness and safety of a combination of two different treatments (mirabegron 50mg and solifenacin 5mg) or solifenacin (5mg or 10mg) alone in patients aged <65 yr or ≥65 yr, and <75 yr or ≥75 yr with overactive bladder. Symptoms of overactive bladder, such as the urgent need to visit the toilet, incontinence, and frequent urination, were improved with all treatments regardless of the patient's age, but combination treatment demonstrated the greatest benefit, and was well tolerated.

Safety and effectiveness of mirabegron in patients with overactive bladder aged ≥75 years: Analysis of a Japanese post-marketing study

OBJECTIVES

A 12-week post-marketing study was conducted to provide real-world data on Japanese patients with overactive bladder (OAB) initiating treatment with mirabegron. This post-hoc analysis focused on safety and effectiveness of mirabegron in patients aged ≥75 versus <75 years.

METHODS

Incidence of adverse drug reactions (ADR) was assessed following 12 weeks' mirabegron treatment. Overactive Bladder Symptom Score (OABSS) and International-Prostate Symptom Score Quality of Life (I-PSS QoL) were completed at baseline and at the end of treatment (EoT). A reduction of ≥3 points in total OABSS was defined as a minimal clinically important change (MCIC).

RESULTS

Of 9795 patients, a greater proportion aged ≥75 versus <75 years had a lower body mass index (BMI; BMI < 18.5: 4.2% vs 3.2%), longer OAB duration (≥3 years: 24.6% vs 20.3%) and more severe OAB symptoms (severe: 17.0% vs 11.2%). A significantly greater percentage of patients aged ≥75 versus <75 years had comorbidities (77.8% vs 66.0%) and used concomitant drugs (58.3% vs 48.7%; P < 0.001). Incidence of ADR was observed in 7.00% and 5.19% of patients aged ≥75 versus <75 years, respectively. At EoT, mirabegron treatment was reported 'effective' in 79.3% versus 82.1% of patients aged ≥75 versus <75 years, respectively. Mean total OABSS decreased significantly from baseline, and exceeded the MCIC in 61.0% and 65.9% of patients aged ≥75 and <75 years, respectively. Similar changes were observed for I-PSS QoL in both groups.

CONCLUSIONS

In a real-world clinical setting, mirabegron was well-tolerated and effective in patients aged ≥75 and <75 years.

Safety issues associated with using medication to treat overactive bladder

INTRODUCTION

The mainstay of overactive bladder treatment is the use of anticholinergic medication with its common side effects well known. This review focused on three less well-known safety issues when treating OAB. Areas covered: Patients with increased anticholinergic load are at risk of cognitive decline, dementia or even death. The elderly are particularly at risk due to polypharmacy. Botulinum toxin carries the risk of high urinary residuals, urinary tract infection and need to self catheterise. The use of vaginal oestrogens may improve OAB symptoms, but there is concern in those with a history of breast cancer. Studies have shown that the systemic absorption is negligible and does not increase the risk of recurrence. Expert Opinion: Improvement in assessing anticholinergic load is needed with the development of a universal drug scale. To avoid increasing load, Mirabegron or botulinum toxin can be used instead. There is no consensus of the use of prophylactic antibiotics when injecting botulinum toxin and at what residual to initiate self catheterisation. Despite evidence showing that the use of vaginal oestrogens is safe in those with a history of cancer, it is not fully supported by any health body. Further work is needed in those using aromatase inhibitors.

Anticholinergic prescription: are healthcare professionals the real burden?

INTRODUCTION AND HYPOTHESIS

Anticholinergic medication is the medical treatment for overactive bladder (OAB). These drugs can act on the central nervous system and can lead to cognitive decline, dementia, and potentially death. Patients taking drugs with anticholinergic effects increase their anticholinergic burden-defined as the cumulative effect of taking one or more drugs that can have adverse effects. When prescribing anticholinergic medication for the elderly, we must choose the right drug. We aimed to discover the level of understanding on this subject and its application to real clinical practice amongst our healthcare professionals (HCPs).

METHODS

An 18-point questionnaire was distributed to urogynaecologists, general gynaecologists, urologists, geriatricians, general practitioners (GPs), and nurse specialists to assess knowledge on the subject.

RESULTS

A total of 96 HCPs completed the questionnaire. The nurse specialists had the highest score in identifying that oxybutynin was the drug most likely to cross the blood-brain barrier (BBB). The urogynaecologists had the highest score in identifying that trospium chloride was least likely to cross the BBB, whereas the GPs had the lowest score. Solifenacin was the most popular anticholinergic drug prescribed in the elderly without dementia. Trospium chloride was the most popular drug prescribed in the elderly with dementia.

CONCLUSIONS

We have found that knowledge is lacking amongst all our HCPs, but especially amongst our first-line doctors, our GPs. Education is key in developing knowledge and safe prescribing, to improve the care we give to our patients.

Oral pharmacotherapy for overactive bladder in older patients: mirabegron as a potential alternative to antimuscarinics

OBJECTIVE

Overactive bladder (OAB) is a particular challenge to treat in older adults with co-morbid conditions taking multiple medications. Antimuscarinics (e.g., solifenacin, fesoterodine) and β3-adrenergic receptor agonists (mirabegron) are similarly efficacious; however, antimuscarinics may be associated with side effects that result in poor persistence and contribute to anticholinergic burden, particularly in those taking other medications with anticholinergic properties. With a mechanism of action distinct from antimuscarinics, mirabegron has a different tolerability profile and does not contribute to anticholinergic burden. The objective of this review was to compare and contrast the tolerability profiles of antimuscarinics and mirabegron in older patients to inform practice.

METHODS

Prospective trials or retrospective subgroup analyses of antimuscarinics for the treatment of OAB in older patients were identified through a search of PubMed. Tolerability data and results of subgroup analyses of mirabegron in patients aged ≥65 and ≥75 years from a pooled analysis of three trials each of 12 weeks and a 1 year trial are described.

RESULTS

Anticholinergic adverse events (AEs) including dry mouth and constipation were more frequent with antimuscarinics versus mirabegron. In patients aged ≥65 years, dry mouth occurred with a six-fold higher incidence with tolterodine extended-release (ER) 4 mg than with mirabegron 25 mg or 50 mg over 12 weeks, and a three-fold higher incidence with tolterodine ER than mirabegron 50 mg over 1 year. Mirabegron had a low incidence of central nervous system effects. A systematic review of the cardiovascular safety profile of mirabegron has not identified any clinically significant effects on blood pressure or pulse rate at therapeutic doses amongst patients aged ≥65 years.

CONCLUSIONS

Mirabegron has a more favorable tolerability profile than antimuscarinics amongst older patients and may provide an improved benefit-to-risk ratio and therefore be considered as an alternative to antimuscarinics for older patients.

Influence of antimuscarinic therapy on cognitive functions and quality of life in geriatric patients treated for overactive bladder

OBJECTIVES

Incidences of overactive bladder (OAB) and cognitive dysfunction increase with aging. Treatment of OAB with antimuscarinic agents may result in cognitive decline, especially in patients with Alzheimer's disease (AD). The aim of this study is to evaluate the effect of antimuscarinic treatment on cognitive functions, depression, and quality of life (QOL) of patients with OAB.

METHODS

This non-interventional prospective observational study was conducted in a geriatric medicine outpatient clinic. Overall, 168 OAB patients were enrolled. Patients were followed up in five groups: oxybutynin, darifenacin, tolterodine, trospium, and control groups. Follow-up visits were done at second, third, and sixth months. Comprehensive geriatric assessment, cognitive and mood assessment, QOL scales (IIQ-7, UDI-6) were performed.

RESULTS

Mean age of the patients was 73.5 ± 6.1. Of the 168 patients, 92.3% were female, 83.3% benefited from the treatment, and 37.1% discontinued the medication. Discontinuation rate and frequency of side effects were more frequent in the oxybutynin group. Mini Mental State Examination scores did not decline after treatment, even in AD patients. Geriatric Depression Scale scores, Activities of Daily Living scores, and QOL scores significantly improved after treatment.

CONCLUSION

Antimuscarinic agents are effective in OAB treatment. They have a positive impact on daily life activities, depression, and QOL indices. Furthermore, they do not have a negative effect on cognitive function in older adults with or without AD.

Morphological changes in the salivary acini after in vivo cholinergic stimulation

AIMS

Overactive bladder syndrome treated by muscarinic receptor antagonists may be complicated by reduced salivation. Cholinergic agonists may reverse this effect. The aim of the present study was to determine the antagonizing effect of a cholinergic agonist (carbachol) on a muscarinic receptor antagonist (oxybutynin) in the submandibular acini in a rat model.

METHODS

Forty male Sprague Dawley rats were divided into three groups: Group I (control), Group II (vehicle), and Group III (treatment). Group III was subdivided so Group IIIa was treated with a muscarinic receptor antagonist (oxybutynin) for 1 week, Group IIIb was treated with oxybutynin for 3 weeks, and Group IIIc was treated with oxybutynin for 1 week and oxybutynin and a cholinergic agonist (carbachol) for 2 weeks. Histological and ultrastructural studies were performed on submandibular glands.

RESULTS

Group IIIa showed moderate atrophic changes in the serous acini and ducts. Group IIIb showed serous acini with distorted wall, widening of the inter-lobar space, and deposition of mononuclear cells in the connective tissue. Group IIIc had serous acini similar to Group I, with mildly dilated inter-lobar ducts, but some serous acini revealed double nuclei and the inter-lobar duct showed luminal vacuolations. Ultrastructural studies confirmed histological results.

CONCLUSIONS

Muscarinic receptor antagonist administration led to changes in the submandibular gland of rats, while concomitant administration of cholinergic agonists seemed to counteract these atrophic changes. Additional studies should assess carbachol as a cholinergic agonist in treating dry mouth in patients with overactive bladder syndrome who are taking the muscarinic receptor. Neurourol. Urodynam. 35:574-581, 2016. © 2015 Wiley Periodicals, Inc.

[Integration of pharmacokinetics and pharmacodynamics based on the in vivo analysis of drug-receptor binding]

  As I was deeply interested in the effects of drugs on the human body, I chose pharmacology as the subject of special study when I became a 4th year student at Shizuoka College of Pharmacy. I studied abroad as a postdoctoral fellow for two years, from 1978, under the tutelage of Professor Henry I. Yamamura (pharmacology) in the College of Medicine at the University of Arizona, USA. He taught me a variety of valuable skills such as the radioreceptor binding assay, which represented the most advanced technology developed in the US at that time. After returning home, I engaged in clarifying receptor abnormalities in pathological conditions, as well as in drug action mechanisms, by making the best use of this radioreceptor binding assay. In 1989, following the founding of the University of Shizuoka, I was invited by Professor Ryohei Kimura to join the Department of Pharmacokinetics. This switch in discipline provided a good opportunity for me to broaden my perspectives in pharmaceutical sciences. I worked on evaluating drug-receptor binding in vivo as a combined index for pharmacokinetics and pharmacological effect manifestation, with the aim of bridging pharmacology and pharmacokinetics. In fact, by focusing on data from in vivo receptor binding, it became possible to clearly rationalize the important consideration of drug dose-concentration-action relationships, and to study quantitative and kinetic analyses of relationships among pharmacokinetics, receptor binding and pharmacological effects. Based on this concept, I was able to demonstrate the utility of dynamic analyses of drug-receptor binding in drug discovery, drug fostering, and the proper use of pharmacokinetics with regard to many drugs.

Safe prescribing of physical health medication in patients with dementia

OBJECTIVE

The prescription of multiple medications for older people is common, despite concerns over the dangers associated with this. Older adults are particularly vulnerable to adverse effects of medication, and this is an even greater risk in patients with dementia. Many drugs used for physical health conditions can negatively affect cognition. Our aim was to identify areas of concern and which drugs to avoid in patients with dementia.

DESIGN

A review of the literature was carried out using Pubmed, Medline and Embase.

RESULTS

Many drugs used for physical health conditions may worsen the symptoms of dementia. They do this either by negating the effects of cognitive enhancers or through direct adverse effects on cognition

CONCLUSIONS

Where evidence exists, we provide guidance as to the safest drugs to prescribe in particular clinical situations. Anticholinergic drugs should be avoided in dementia wherever possible. Effective pain management is important in older patients, but caution should be used when selecting an opioid analgesic because of their adverse central effects. Cardiac drugs have overall negligible effects on cognition, although some have been reported to cause delirium.

The efficacy and tolerability of the β3-adrenoceptor agonist mirabegron for the treatment of symptoms of overactive bladder in older patients

INTRODUCTION

mirabegron is a β3-adrenoceptor agonist developed for the treatment of symptoms of overactive bladder (OAB). As the prevalence of OAB increases with age, a prospective subanalysis of individual and pooled efficacy and tolerability data from three 12-week, randomised, Phase III trials, and of tolerability data from a 1-year safety trial were conducted in order to evaluate the efficacy and tolerability of mirabegron in subgroups of patients aged ≥65 and ≥75 years.

METHODS

primary efficacy outcomes were change from baseline to final visit in the mean number of incontinence episodes/24 h and the mean number of micturitions/24 h. Tolerability was assessed by the incidence of treatment-emergent adverse events (TEAEs).

RESULTS

over 12 weeks mirabegron 25 mg and 50 mg once-daily reduced the mean numbers of incontinence episodes and micturitions/24 h from baseline to final visit in patients aged ≥65 and ≥75 years. Mirabegron was well tolerated: in both age groups, hypertension and urinary tract infection were among the most common TEAEs over 12 weeks and 1 year. The incidence of dry mouth, a typical anticholinergic TEAE, was up to sixfold higher among the older patients randomised to tolterodine than any dose of mirabegron.

CONCLUSIONS

these analyses have demonstrated the efficacy of mirabegron over 12 weeks and the tolerability of mirabegron over 12 weeks and 1 year in OAB patients aged ≥65 and ≥75 years, supporting mirabegron as a therapeutic option in older patients with OAB.

Safety and tolerability of the β3 -adrenoceptor agonist mirabegron, for the treatment of overactive bladder: results of a prospective pooled analysis of three 12-week randomised Phase III trials and of a 1-year randomised Phase III trial

AIMS

To evaluate the safety and tolerability of the β3 -adrenoceptor agonist, mirabegron, in patients with overactive bladder (OAB).

METHODS

Tolerability and safety data from three 12-week, randomised, placebo-controlled, double-blind, Phase III trials (Studies 046, 047 and 074) were pooled by treatment group. The three studies were of a similar design, although the assessed doses of mirabegron [25, 50 or 100 mg once daily (qd)] varied, and tolterodine extended release (ER) 4 mg was included as an active-control arm in Study 046 only. Tolerability and safety data from a 1-year, randomised, double-blind, Phase III trial (Study 049) are also presented. Safety variables included the incidence and severity of treatment-emergent adverse events (TEAEs), vital signs and electrocardiogram data.

RESULTS

Mirabegron (25, 50 or 100 mg qd) was safe and well-tolerated in patients with OAB over 12-week (n = 2736) and 1-year (n = 1632) periods. The incidence of TEAEs and treatment discontinuations as a result of TEAEs was low; the majority were mild in severity and few were serious. Hypertension, nasopharyngitis and urinary tract infection were the most common TEAEs with mirabegron. The mirabegron tolerability profile was similar to that seen with placebo and tolterodine ER 4 mg, except for dry mouth, which occurred, on average, five times less frequently with mirabegron than tolterodine ER 4 mg. In the pooled 12-week analysis, mirabegron 50 mg was associated with placebo-adjusted mean increases of 0.4-0.6 mmHg in blood pressure and approximately one beat per minute in pulse rate, both reversible upon treatment discontinuation. The incidence of Major Adverse Cardiovascular Events as adjudicated by an independent cardiovascular committee was low and similar across treatment groups.

CONCLUSION

The favourable tolerability profile of mirabegron in patients with OAB may allow improved treatment compliance compared with antimuscarinics, with important implications for patient outcomes.

Health-related quality of life and economic impact of urinary incontinence due to detrusor overactivity associated with a neurologic condition: a systematic review

BACKGROUND

Patients with neurologic diseases often have neurogenic detrusor overactivity (NDO), which can result in a loss of voluntary bladder control and uncontrollable urinary incontinence (UI).The impact of UI due to NDO on patients' lives has not been well studied. The objective of this review was to assess the health-related quality of life (HRQoL) and economic burden in patients with urgency UI due to NDO in select countries in North America, the European Union, Asia, and Australia.

METHODS

Systematic literature searches and reviews of articles published in English (January 2000 to February 2011) were conducted using MEDLINE®, EMBASE®, and the Cochrane Library. Studies assessing the impact of UI on HRQoL of patients with an underlying neurologic condition of interest (i.e., multiple sclerosis, spinal cord injury, Parkinson's disease, stroke, or spina bifida) were included. Economic studies in urgency UI also were included.

RESULTS

Of 876 citations generated in the initial search, a total of 27 articles were deemed relevant: 16 articles presented HRQoL data and 11 articles presented information on the economic burden of UI. Humanistic studies used a range of HRQoL instruments to measure HRQoL burden, and the economic studies included different cost components to quantify the economic burden, making meaningful comparisons challenging. Despite this heterogeneity, the literature suggests that HRQoL in patients with UI due to NDO is worse than patients with UI in general or those with the same underlying neurologic condition without UI. In addition, urgency UI also results in substantial economic costs.

CONCLUSIONS

Incontinent patients with underlying neurologic conditions have impaired HRQoL as well as substantial economic burden attributable to UI due to NDO. There is a need for urgency UI treatments that improve HRQoL of these patients and alleviate the economic burden of this condition.

Characterization of bladder selectivity of antimuscarinic agents on the basis of in vivo drug-receptor binding

The in vivo muscarinic receptor binding of antimuscarinic agents (oxybutynin, solifenacin, tolterodine, and imidafenacin) used to treat urinary dysfunction in patients with overactive bladder is reviewed. Transdermal administration of oxybutynin in rats leads to significant binding of muscarinic receptors in the bladder without long-term binding in the submaxillary gland and the abolishment of salivation evoked by oral oxybutynin. Oral solifenacin shows significant and long-lasting binding to muscarinic receptors in mouse tissues expressing the M₃ subtype. Oral tolterodine binds more selectively to muscarinic receptors in the bladder than in the submaxillary gland in mice. The muscarinic receptor binding of oral imidafenacin in rats is more selective and longer-lasting in the bladder than in other tissues such as the submaxillary gland, heart, colon, lung, and brain, suggesting preferential muscarinic receptor binding in the bladder. In vivo quantitative autoradiography with (+)N-[¹¹C]methyl-3-piperidyl benzilate in rats shows significant occupancy of brain muscarinic receptors with the intravenous injection of oxybutynin, solifenacin, and tolterodine. The estimated in vivo selectivity in brain is significantly greater for solifenacin and tolterodine than for oxybutynin. Imidafenacin occupies few brain muscarinic receptors. Similar findings for oral oxybutynin were observed with positron emission tomography in conscious rhesus monkeys with a significant disturbance of short-term memory. The newer generation of antimuscarinic agents may be advantageous in terms of bladder selectivity after systemic administration.

Botulinum toxin in neurogenic detrusor overactivity

Purpose

To evaluate the effects of botulinum toxin on urodynamic parameters and quality of life in patients with neurogenic detrusor overactivity.

Methods

Thirty four adult patients with spinal cord injury and detrusor overactivity were selected. The patients received 300 units of botulinum toxin type A. The endpoints evaluated with the episodes of urinary incontinence and measured the maximum cystometric capacity, maximum amplitude of detrusor pressure and bladder compliance at the beginning and end of the study (24 weeks) and evaluated the quality of life by applying the Qualiveen questionnaire.

Results

A significant decrease in the episodes of urinary incontinence was observed. All urodynamic parameters presented a significant improvement. The same was observed in the quality of life index and the specific impact of urinary problems scores from the Qualiveen questionnaire. Six patients did not complete the study, two due to incomplete follow-up, and four violated protocol and were excluded from the analyses. No systemic adverse events of botulinum toxin type A were reported.

Conclusions

A botulinum toxin type A showed a significantly improved response in urodynamics parameters and specific and general quality of life.

Evaluation of cognitive function in healthy older subjects treated with fesoterodine

OBJECTIVE

To evaluate the cognitive effects of fesoterodine 4 and 8 mg versus placebo in healthy older adults.

METHODS

This was an active- and placebo-controlled, double-blind, double-dummy crossover study conducted using healthy volunteers (aged 65-85 years) with baseline Mini-Mental State Examination score ≥ 26. The study comprised 4 treatment periods: fesoterodine 4 mg for 6 days; fesoterodine 4 mg for 3 days followed by fesoterodine 8 mg for 3 days; placebo for 6 days; and placebo for 6 days with alprazolam 1 mg on day 6. The treatment sequence was randomized, with a 3- to 6-day washout between periods. Subjects completed computer-based cognitive assessments and the Rey Auditory Verbal Learning Test on day 1 (before dosing) and day 6 (after dosing) of each period. The primary endpoint was the Detection task; secondary endpoints were the Identification task, 1-card learning task, Continuous Paired Associate Learning task, Groton Maze Learning Task, and the Rey Auditory Verbal Learning Test.

RESULTS

Among 18 subjects in the per protocol set, changes from baseline to day 6 with fesoterodine 4 and 8 mg were not significantly different from placebo for any endpoint (P > 0.05); alprazolam produced significant impairment in all endpoints versus placebo (P < 0.05). No serious adverse events were reported; the most common adverse events were dry mouth for fesoterodine and sedation for alprazolam. No sedation was reported with fesoterodine.

CONCLUSION

In healthy older adults, fesoterodine 4 and 8 mg once daily had no statistically significant effects versus placebo on any cognitive function assessed, including memory; alprazolam 1 mg produced statistically significant deterioration.

An overview on mixed action drugs for the treatment of overactive bladder and detrusor overactivity

OBJECTIVES

To provide an overview on the efficacy, tolerability, safety and health-related quality of life (HRQoL) of drugs with a mixed action used in the treatment of overactive bladder (OAB).

EVIDENCE ACQUISITION

MEDLINE database and abstract books of the major conferences were searched for relevant publications from 1966 to 2011 and using the key words 'overactive bladder', 'detrusor overactivity', 'oxybutynin', 'propiverine', and 'flavoxate'. Two independent reviewers considered publications for inclusion and extracted relevant data, without performing a meta-analysis.

EVIDENCE SYNTHESIS

Old and conflicting data do not support the use of flavoxate, while both propiverine and oxybutynin were found to be more effective than placebo in the treatment of OAB. Propiverine was at least as effective as oxybutynin but with a better tolerability profile even in the pediatric setting. Overall, no serious adverse event for any product was statistically significant compared to placebo. Improvements were seen in HRQoL with treatment by the oxybutynin transdermal delivery system and propiverine extended release.

CONCLUSIONS

While there is no evidence to suggest the use of flavoxate in the treatment of OAB, both oxybutynin and propiverine appear efficacious and safe. Propiverine shows a better tolerability profile than oxybutynin. Both drugs improve HRQoL of patients affected by OAB. Profiles of each drug and dosage differ and should be considered in making treatment choices.

Antimuscarinic drugs: review of the cognitive impact when used to treat overactive bladder in elderly patients

The blockade of muscarinic receptors in the management of overactive bladder (OAB) symptoms provides beneficial as well as adverse effects. The cognitive changes observed are caused by the drugs' ability to cross the blood-brain barrier and bind to muscarinic receptors within the central nervous system (CNS). To date, while not specifically testing for CNS side effects, most of the controlled efficacy trials of multiple OAB medications have not shown significant adverse effects on cognitive function. However, elderly individuals, in whom OAB is more prevalent, often are excluded from these studies. The few trials that have performed cognitive testing in healthy elderly people taking antimuscarinics have clearly shown that oxybutynin can adversely affect cognition. Darifenacin, trospium, solifenacin, and tolterodine appear to have little to no risk of causing CNS side effects in this population. However, caution needs to be used in elderly patients with preexisting dementia.

A comprehensive non-clinical evaluation of the CNS penetration potential of antimuscarinic agents for the treatment of overactive bladder

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

This study provides antimuscarinic agents for overactive bladder (OAB) display variable association with side effects mediated by the central nervous system (CNS), which may be of particular concern in the elderly. Adverse effects on CNS functioning are related to muscarinic receptor subtype selectivity and the ability of the agent to cross the blood-brain barrier, where P-gp plays a role in limiting permeability.

WHAT THIS STUDY ADDS

This study provides a parallel investigation of CNS penetration of antimuscarinic OAB agents in vivo and assessment of physical properties and permeability in cell monolayers in vitro. It adds further understanding of the roles of passive transcellular permeability and P-gp in determining CNS penetration of antimuscarinic OAB agents. It also enables a comparison of CNS side-effect profiles of OAB agents with preclinical CNS penetration data.

AIMS

To assess and compare the mechanisms of central nervous system (CNS) penetration of antimuscarinic overactive bladder (OAB) agents.

METHODS

Physical properties were computed or compiled from the literature. Rats were administered 5-hydroxymethyl tolterodine (HMT), darifenacin, oxybutynin, solifenacin, tolterodine or trospium subcutaneously. At 1 h postdose, plasma, brain and cerebrospinal fluid (CSF) concentrations were determined using LC-MS/MS assays. Brain and plasma protein binding were determined in vitro. Permeability in the presence and absence of the efflux transporter P-glycoprotein (P-gp) was assessed in RRCK and MDCK-MDR1 transwell assays.

RESULTS

Oxybutynin displayed extensive CNS penetration, with brain:plasma ratios (B:P), unbound brain:unbound plasma ratios (Kp,free) and CSF:free plasma ratios each >1. Tolterodine (B:P = 2.95, Kp,free = 0.23 and CSF:free plasma = 0.16) and solifenacin (B:P = 3.04, Kp,free = 0.28 and CSF:free plasma = 1.41) showed significant CNS penetration but with some restriction from CNS as indicated by Kp,free values significantly <1. 5-HMT, darifenacin and trospium displayed much lower B:P (0.03-0.16), Kp,free (0.01-0.04) and CSF:free plasma (0.004-0.06), consistent with poor CNS penetration. Permeability in RRCK cells was low for trospium (0.63 × 10(-6) cm s(-1) ), moderate for 5-HMT (11.7 × 10(-6) cm s(-1) ) and high for darifenacin, solifenacin, tolterodine and oxybutynin (21.5-38.2 × 10(-6) cm s(-1) ). In MDCK-MDR1 cells 5-HMT, darifenacin and trospium, were P-gp substrates, whereas oxybutynin, solifenacin and tolterodine were not P-gp substrates.

CONCLUSIONS

Brain penetration was low for antimuscarinics that are P-gp substrates (5-HMT, darifenacin and trospium), and significant for those that are not P-gp substrates (oxybutynin, solifenacin and tolterodine). CNS adverse events reported in randomized controlled clinical trials show general alignment with the preclinical data described in this study.

In vitro safety pharmacology profiling: what else beyond hERG?

One of the main reasons for drug failures in clinical development, or postmarket launch, is lacking or compromised safety margins at therapeutic doses. Organ toxicity with poorly defined mechanisms and adverse drug reactions associated with on- and off-target effects are the major contributors to safety-related shortfalls of many clinical drug candidates. Therefore, to avoid high attrition rates in clinical trials, it is imperative to test compounds for potential adverse reactions during early drug discovery. Beyond a small number of targets associated with clinically acknowledged adverse drug reactions, there is little consensus on other targets that are important to consider at an early stage for in vitro safety pharmacology assessment. We consider here a limited number of safety-related targets, from different target families, which were selected as part of in vitro safety pharmacology profiling panels integrated in the drug-development process at Novartis. The best way to assess these targets, using a biochemical or a functional readout, is discussed. In particular, the importance of using cell-based profiling assays for the characterization of an agonist action at some GPCRs is highlighted. A careful design of in vitro safety pharmacology profiling panels allows better prediction of potential adverse effects of new chemical entities early in the drug-discovery process. This contributes to the selection of the best candidate for clinical development and, ultimately, should contribute to a decreased attrition rate.

Antimuscarinics for the treatment of overactive bladder: understanding the role of muscarinic subtype selectivity

INTRODUCTION AND HYPOTHESIS

Antimuscarinic agents appear to exert their therapeutic activity in overactive bladder (OAB) via blockade of the M(3) muscarinic receptor subtype. Antimuscarinics are broadly similar in efficacy, but their safety and tolerability profiles vary, which may reflect differences in muscarinic receptor selectivity profiles.

METHODS

This review of available literature aims to determine whether antimuscarinic agents with greater M(3) selectivity have clinical advantages over less selective drugs.

RESULTS

Antimuscarinic agents differ widely in their propensity to cause cognitive and cardiovascular (CV) effects, which appear mainly to be related to differences in their relative selectivity for binding to non-M(3) receptors, including M(1) receptors in the brain and cardiac M(2) receptors.

CONCLUSIONS

Cognitive and CV effects are especially pertinent for the OAB patient who tends to be older with various comorbidities and is often taking multiple medications. Hence, it is important to consider the risk/benefit balance of antimuscarinic agents when selecting OAB treatment.

Anticholinergics for overactive bladder therapy: central nervous system effects

The mainstay of pharmacological treatment of overactive bladder (OAB) is anticholinergic therapy using muscarinic receptor antagonists (tertiary or quaternary amines). Muscarinic receptors in the brain play an important role in cognitive function, and there is growing awareness that antimuscarinic OAB drugs may have adverse central nervous system (CNS) effects, ranging from headache to cognitive impairment and episodes of psychosis. This review discusses the physicochemical and pharmacokinetic properties of OAB antimuscarinics that affect their propensity to cause adverse CNS effects, as observed in phase III clinical trials and in specific investigations on cognitive function and sleep architecture. PubMed/MEDLINE was searched for "OAB" plus "muscarinic antagonists" or "anticholinergic drug." Additional relevant literature was identified by examining the reference lists of papers identified through the search. Preclinical and clinical trials in adults were assessed, focusing on the OAB antimuscarinics approved in the United States. The blood-brain barrier (BBB) plays a key role in protecting the CNS, but it is penetrable. The lipophilic tertiary amines, particularly oxybutynin, are more likely to cross the BBB than the hydrophilic quaternary amine trospium chloride, for which there are very few reports of adverse CNS effects. In fact, in 2008 the US product labels for oral oxybutynin were modified to include the potential for anticholinergic CNS events and a warning to monitor patients for adverse CNS effects. Even modest cognitive impairment in the elderly may negatively affect independence; therefore, selection of an antimuscarinic OAB drug with reduced potential for CNS effects is advisable.

Tolerability of solifenacin and oxybutynin immediate release in older (> 65 years) and younger (≤ 65 years) patients with overactive bladder: sub-analysis from a Canadian, randomized, double-blind study

OBJECTIVE

Overactive bladder (OAB) is a common condition whose prevalence increases with age. Antimuscarinic agents are the pharmacologic treatment of choice, but adverse events such as dry mouth may lead to early discontinuation. The purpose of this analysis was to compare the incidence and severity of dry mouth and other adverse events with solifenacin 5 mg/day and oxybutynin immediate release (IR) 15 mg/day in patients ≤ 65 years and >65 years in the Canadian VECTOR study (VEsicare in Comparison To Oxybutynin for oveRactive bladder patients).

RESEARCH DESIGN AND METHODS

VECTOR was a randomized, multicentre, prospective, double-blind, double-dummy study in 132 subjects with ≥ 1 urgency episode per 24 h, with or without urgency incontinence, and ≥ 8 micturitions per 24 h for ≥ 3 months. After a 2-week washout, patients received solifenacin 5 mg once daily or oxybutynin IR 5 mg tid for 8 weeks. For the current post-hoc analysis, adverse events were evaluated in subgroups of patients ≤ 65 years and >65 years, using a full logistic regression model, multinomial logit regression model and reduced model.

CLINICAL TRIAL REGISTRATION

NCT00431041.

RESULTS

The incidence and severity of dry mouth and other adverse events with solifenacin were similar between younger and older patients. In both age subgroups, solifenacin 5 mg/day was associated with fewer episodes and lower severity of dry mouth, and a lower discontinuation rate, compared with oxybutynin IR 15 mg/day.

CONCLUSIONS

Solifenacin 5 mg/day was better tolerated than oxybutynin IR 15 mg/day in younger (≤ 65 years) and older (> 65 years) subgroups. Solifenacin was equally well tolerated in both age subgroups. Limitations of the analysis were that the study was not preplanned to perform post-hoc subgroup analysis, patients knew that dry mouth was a primary outcome, and the study used fixed doses of each drug.

Major urologic problems in geriatrics: assessment and management

Elderly urologic patients require the same cautions as used in development of treatment programs for them in other disciplines. Because of potential interference with poor renal function or crossover effects with central or peripheral nervous system, however, many urologic drugs must be titrated appropriately. In treating cancer, erectile dysfunction, incontinence or urinary infection, patient quality of life and life span become dominant factors in making therapeutic decisions, by behavioral change, medication, or surgical intervention.

Development of a unidimensional composite measure of neuropsychological functioning in older cardiac surgery patients with good measurement precision

The objective of this analysis was to develop a measure of neuropsychological performance for cardiac surgery and to assess its psychometric properties. Older patients (n = 210) underwent a neuropsychological battery using nine assessments. The number of factors was identified with variable reduction methods. Factor analysis methods based on item response theory were used to evaluate the measure. Modified parallel analysis supported a single factor, and the battery formed an internally consistent set (coefficient alpha = .82). The developed measure provided a reliable, continuous measure (reliability > .90) across a broad range of performance (-1.5 SDs to +1.0 SDs) with minimal ceiling and floor effects.

Pharmacologic therapy for the neurogenic bladder

This article is a review of the current and past literature on medical management of the neurogenic bladder, with a particular focus on spinal cord injury and multiple sclerosis. The use of antimuscarinics, αα-blocker, and tricyclic antidepressants and their combined use are discussed along with new therapies in human and animal trials.

Trospium chloride has no effect on memory testing and is assay undetectable in the central nervous system of older patients with overactive bladder

BACKGROUND

Muscarinic receptors in the brain play an important role in cognitive function, especially memory, and there is growing awareness that specific antimuscarinic drugs for overactive bladder (OAB) may have adverse central nervous system (CNS) effects. Selection of an antimuscarinic OAB drug with reduced potential for CNS effects could be especially beneficial in the elderly people, in whom even the modest cognitive impairment may negatively affect independence.

PURPOSE

The purpose of the study is to determine if trospium chloride is assay detectable in the CNS of older adults with OAB and to assess whether deterioration of memory occurs in these individuals.

METHODS

Twelve cognitively intact older adults (>or=65-75 years old) with OAB were given extended-release trospium chloride 60 mg once daily over a 10-day period to achieve plasma steady-state levels. Standardised memory testing (Hopkins Verbal Learning Test-Revised and Brief Visuospatial Memory Test-Revised) was performed predose and postdose. Cerebrospinal spinal fluid (CSF) and plasma samples were drawn on day 10 and assayed for trospium chloride. Predose (day 0) and postdose (day 10) results on the memory tests were compared using a reliable change index to assess a meaningful change in learning or memory.

RESULTS

Trospium chloride levels in all the CSF samples (n = 72) of all participants were assay undetectable (<40 pg/ml) on day 10 at steady-state peak plasma concentration concurrent with measureable peak plasma values (C(max) = 925 pg/ml). Repeat memory testing revealed no significant net drug effect on learning or recall.

CONCLUSIONS

This is the first study to investigate for the presence of an OAB antimuscarinic in the human brain, performed by assaying for concentrations of trospium chloride and correlating with simultaneous clinical cognitive safety measures. The results of both pharmacological and neuropsychological testing support the hypothesis of a lack of detectable CNS penetration for the quaternary amine trospium chloride.

The forefront for novel therapeutic agents based on the pathophysiology of lower urinary tract dysfunction: bladder selectivity based on in vivo drug-receptor binding characteristics of antimuscarinic agents for treatment of overactive bladder

We have reviewed the binding of antimuscarinic agents, used to treat urinary dysfunction in patients with overactive bladder, to muscarinic receptors in target and non-target tissues in vivo. Transdermal administration of oxybutynin in rats led to significant binding in the bladder without long-term binding in the submaxillary gland and the abolishment of salivation evoked by oral oxybutynin. Oral solifenacin showed significant and long-lasting binding to muscarinic receptors in mouse tissues expressing the M(3) subtype. Oral tolterodine bound more selectively to muscarinic receptors in the bladder than in the submaxillary gland in mice. The muscarinic receptor binding activity of oral darifenacin in mice was shown to be pronounced and long-lasting in the bladder, submaxillary gland, and lung. In vivo quantitative autoradiography using (+)N-[(11)C]methyl-3-piperidyl benzilate in rats showed significant occupancy of brain muscarinic receptors on intravenous injection of oxybutynin, propiverine, solifenacin, and tolterodine. The estimated in vivo bladder selectivity compared to brain was significantly greater for solifenacin and tolterodine than oxybutynin. Darifenacin occupied few brain muscarinic receptors. Similar findings were also observed with positron emission tomography in conscious rhesus monkeys. The newer generation of antimuscarinic agents may be advantageous in the bladder selectivity after systemic administration.

Synthesis of a quaternary bis derivative of imipramine as a novel compound with potential anti-enuretic effect

Objectives

Imipramine has been used for over four decades (early reports in 1960s) for the treatment of nocturnal enuresis, although the reason for its effect is not clear. Imipramine is a tertiary amine, which may act both in the periphery and/or pass through the blood-brain barrier (BBB) in unionized form and exhibit a central effect. Since imipramine has anti-cholinergic properties, some believe it may exert its anti-enuretic effect by affecting peripheral cholinergic receptors, i.e. its anti-enuretic effect may be due to peripheral anti-cholinergic properties, whereas others think it can pass through the BBB and interact with central nervous system (CNS) receptors. If the anti-enuretic effect of imipramine is due to its peripheral anti-cholinergic effects, its entrance into the CNS is unnecessary. Therefore, the synthesis of a form of imipramine that can exhibit peripheral anti-cholinergic effects but does not have CNS adverse effects would have a safer drug profile in this case. On the other hand, if the anti-enuretic effect of imipramine is primarily due to its action on the CNS, a form of imipramine that cannot pass through the BBB has no effect on nocturnal enuresis treatment and thus may help to clarify the mechanism of action of imipramine in nocturnal enuresis treatment.

Methods

This article describes the synthesis and evaluation of the anti-cholinergic effect of a new bis derivative of imipramine, which contains two imipramine units in its structure.

Key findings

The compound exhibited anti-cholinergic activity comparable with that of imipramine on isolated guinea pig ileum.

Conclusions

Being a quaternary ammonium, this compound is not expected to be able to cross the BBB and thus would cause fewer CNS side effects.

Perspectives on overactive bladder in the elderly population

INTRODUCTION

Overactive bladder (OAB) represents a disruption in the storage function of the lower urinary tract. This bothersome condition occurs more commonly in the elderly. Since population forecasts predict a worldwide increase in the proportion of people aged over 65 years, it is reasonable to expect that the healthcare burden associated with OAB will also increase. The pathophysiology of OAB in the elderly is thought to be multifactorial, with an abnormality occurring in the nervous supply and/or the structure/function of the urothelium or bladder smooth muscle, leading to bladder hypersensitivity, abnormalities in bladder sensation (urgency) and involuntary detrusor contraction.

METHODS

A review of some of the key aspects relating to management of this growing population was undertaken.

RESULTS

The potential for an elderly patient to present with a number of concomitant conditions means that careful characterization of their overall status is required before deciding on the most appropriate management option for their urinary tract pathology. Lifestyle interventions and pharmacological agents have shown success in treating OAB in the elderly, but as this patient group often has many concomitant conditions they are more likely to be seen by a non-urology specialist.

CONCLUSIONS

It is therefore important to raise awareness of the condition and an appreciation of its impact among healthcare professionals to ensure the most appropriate care.