Antimuscarinic drugs to treat overactive bladderBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.e2130 (Published 27 March 2012) Cite this as: BMJ 2012;344:e2130
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In their recent article Robinson and Cardozo1 have given a good account of the usefulness of antimuscarinic drugs to treat overactive bladder. However we feel that the treatment of overactive bladder in elderly patients with dementia was overlooked. Overactive bladder is more common in the elderly where it causes a negative effect on the quality of life2.
The authors have quoted that 30.9 % of women over 65 years have this condition. Studies have shown that 40 % of patients with Alzheimer’s dementia suffer from overactive bladder 3. Many of these patients are taking Acetylcholinestrase (AChE) inhibitors like Donepezil, Galantamine and Rivastigmine. AChE fall under the parasympathomimetics group of medications whose effects are antagonised by antimuscarinic drugs4. This was not included by the authors in their article (Box 3)1.
Treatment of overactive bladder in patients with dementia on AChE remains difficult. One pilot study3 looked at using propiverine hydrochloride, a peripheral muscuranic receptor antagonist used in the treatment of overactive bladder, in patients taking Donepezil for cognitive impairment. This study found improvement in overactive bladder symptoms without changes in cognition. However more research is required in this field.
1. Robinson D, Cardozo L, Antimuscarinic drugs to treat overactive bladder. BMJ 2012 344: e2130 (14 April)
2. Kay GG, Granville LJ, Antimuscarinic agents: implications and concerns in management of overactive bladder in the elderly. Clinical Therapeutics 2005 ; 27 :127-138.
3. Sakakibara R, Ogata T, Uchiyama T, Kishi M, Ogawa E, Isaka S et al. How to manage overactive bladder in elderly individuals with Dementia ? Combined use of Donepezil, a central Acetylcholiestrase inhibitor and Propiverine, a peripheral muscarine receptor antagonist. Journal of American Geriatric Society 2009; 57: 1515-1517.
4. British National Formulary.61st edition. London: BMJ Group and Pharmaceutical Press; 2011
Competing interests: No competing interests
Robinson and Cardozo understate the effects of antimuscarinic drugs on cognition, especially in those with underlying dementia (1). The small randomised studies quoted, which showed low rates of cognitive disturbance, excluded patients with dementia. Yet older adults with dementia are more likely to be prescribed antimuscarinic drugs than those without (2).
Unfortunately, the authors’ list of drug interactions does not include the cholinesterase inhibitors used in Alzheimer’s disease. Basic pharmacology dictates that these two groups of drugs will diminish each other’s therapeutic actions, yet concomitant use is commonplace (2) and antimuscarinic therapy results clinically in a nullification of the effects of Alzheimer’s treatment (3). As cholinesterase inhibitors can worsen urinary incontinence, patients taking them are even more likely to be prescribed antimuscarinics than other patients with dementia (4).
The article does not differentiate between selective M3 receptor antagonists such as solifenacin and non-selective antimuscarinics such as oxybutynin. As M1 and M2 receptors predominate in the mediation of cognitive function (5), selective M3 antagonists may be preferable for overactive bladder in patients with dementia, but research on these agents is needed in this specific patient group.
I am, Madam, your obedient servant,
Dr Rich Braithwaite
Consultant Old Age Psychiatrist
Isle of Wight NHS Trust
St Mary’s Hospital, Newport, Isle of Wight, PO30 5TG, UK
1. Robinson D, Cardozo, L. Antimuscarinic drugs to treat overactive bladder. BMJ 2012;344:e2130.
2. Roe CM, Anderson MJ, Spivack B. Use of anticholinergic medications by older adults with dementia. J Am Geriatr Soc 2002;50:836-42.
3. Lu CJ, Tune LE. Chronic exposure to anticholinergic medications adversely affects the course of Alzheimer disease. Am J Geriatr Psychiatry 2003;11:458-61.
4. Gill SS, Mamdani M, Naglie G, Streiner DL, Bronskill SE, Kopp A, Shulman KI, Lee PE, Rochon PA. A prescribing cascade involving cholinesterase inhibitors and anticholinergic drugs. Arch Intern Med. 2005;165:808-13.
5. Kay GG, Abou-Donia MB, Messer WS, Murphy DG, Tsao JW, Ouslander JG. Antimuscarinic drugs for overactive bladder and their potential effects on cognitive function in older patients. J Am Geriatr Soc 2005;53:2195-201.
Competing interests: No competing interests