The cognitive safety of antimuscarinics in the treatment of overactive bladder

ABSTRACT

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.

KEYWORDS:

• Anticholinergic load
• antimuscarinic
• cognitive impairment
• dementia
• overactive bladder

Article highlights

• Overactive bladder (OAB) describes the symptom complex of urinary urgency, usually accompanied by frequency and nocturia, with or without urgency urinary incontinence.

• The prevalence increases with age, with significant socioeconomic impact.

• The main medical treatment of OAB is with the use of antimuscarinic medication.

• Antimuscarinics can cross the blood-brain barrier and block muscarinic receptors in the brain, exerting central nervous system side effects such as cognitive impairment.

• Anticholinergic load is defined as the side effects caused by a combination of drugs with antimuscarinic properties.

• There is evidence to suggest that antimuscarinics and a high anticholinergic load, increases the risk of dementia and mortality.

• Oxybutynin is a tertiary amine and is most likely to cross the blood-brain barrier and lead to these risks.

• Trospium chloride is a quaternary amine and less likely to cross the blood-brain barrier and theoretically less likely to lead to cognitive side effects,

• Alternatively mirabegron can be used, as it does not add to the anticholinergic load.

This box summarizes key points contained in the article.

Declaration of interest

D Robinson has received support from Astellas, Allergan, Femeda, Ferring, and Ixaltis. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership, or options, expert testimony, grants, or patents received or pending, or royalties.

Reviewer disclosures

An reviewer on this manuscript has disclosed that in the OAB field they are a consultant and lecturer to Apogepha, Astellas, and Velicept. They are also a shareholder of Velicept. All other peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.