Anticholinergic medications are used to block the neurotransmitter acetylcholine. Anticholinergics have systemic effects on smooth muscle function including the lungs, gastrointestinal system and urinary tract. Anticholinergic drugs are therefore prescribed to treat a variety of medical conditions including Parkinson’s disease, allergies, chronic obstructive pulmonary disease, depression and urinary incontinence.
Medications with anticholinergic properties can be associated Adverse Drug Reactions (ADRs). Examples of such ADRs include dry eyes, urinary retention, dizziness, cognitive impairment and falls. The anticholinergic effect increases if a stronger anticholinergic is used, or if different anticholinergics are used in combination. Older patients are more likely to have multiple co- morbidities, and therefore to be on multiple medications. As the body ages, its ability to metabolise medications declines, the permeability of their blood-brain barrier increases and therefore older patients are more susceptible to the anticholinergic effects of their medications1-3.
Anticholinergic burden scales were created in an attempt to quantify the effects of these medications, and provide a practical tool for optimising prescribing for older patients4. Longitudinal studies have shown an association between the use of Anticholinergics and the risk of developing cognitive impairment and of death5. Research also indicates that there is a dose- dependent association between long term use of Anticholinergics and the risk of developing Dementia6.
There is a plethora of literature on anticholinergic burden, including 22 different published scales. These scales are generally formulated by an expert team combining results of research into anticholinergic properties of medications along with their own clinical expertise. We are keen to provide reliable information and therefore have chosen to combine the scores of 2 different scales which we believe to be of the highest quality. These include the anticholinergic cognitive burden scale (ACB)4 and the German anticholinergic burden scale (GABS)7
Many medications that have anticholinergic properties are prescribed on the basis of robust clinical evidence. It is therefore appropriate that these be continued. The purpose of the Anticholinergic Burden Calculator is to aid the clinician in their decision-making during a medication review, and to offer alternatives with a lower Anticholinergic burden, which may or may not be appropriate for that patient.
1 Polypharmacy and Medicines Optimisation in Older People. East Cheshire NHS Prescribing Commissioning Policy August 2016
2 Flacker J, Cummings V, Mach J, BEttin K, Kiely D, Wei J The Association of Serum Anticholinergic Activity with Delirium in Elderly Patients. The American Journey of Geriatric Psychiatry (6:31-41, 1998)
3 Roe C, Anderson M, Spivack B. Use of Anticholinergic Medication by Older Adults with Dementia. Journal of the American Geriatric Society (50:836-842, 2002)
4 Boustani M, Campbell N, Munger S, Maidment I, Fox C. Impact of Anticholinergics on the Ageing Brain; a review and practical application. Ageing Health (4(3) 311-320, 2008)
5 Fox C, Richardson K, Maidment I, Savva G, Matthews F, Smithard D, Coulton S, Katona C, Boustani M, Brayne C. Anticholinergic Medication Use and Cognitive Impairment in the Older Population; The Medical Research Council Cognitive Function and Ageing Study. Journal of the American Geriatric Society. (59;1477-1483, 2011)
6 Gray S, Anderson M, Dublin S. Cumulative Use of Strong Anticholinergic Medications and Incident Dementia. Journal of the American Medical Association. (175(3): 401-407, 2015)
7 Kiesel, E. K., Hopf, Y. M., & Drey, M. (2018). An anticholinergic burden score for german prescribers: Score development. BMC Geriatrics, 18. doi: https://doi.org/10.1186/s12877-018-0929-6
8 Lisibach, A., Benelli, V., Ceppi, M.G. et al. Quality of anticholinergic burden scales and their impact on clinical outcomes: a systematic review. Eur J Clin Pharmacol 77, 147–162 (2021). doi: https://doi.org/10.1007/s00228-020-02994-x