Anticholinergic Burden

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, and therefore older patients are more susceptible to the Anticholinergic effects of their medications1-3.

Anticholinergic Burden tables were created in 2008 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. More recent research also indicates that there is a dose-dependent association between long term use of Anticholinergics and the risk of developing Dementia6.

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.


References

1 Polypharmacy and Medicines Optimisation in Older People. East Cheshire NHS Prescribing Commissioning Policy August 2016

2 Flacker et al. The Association of Serum Anticholinergic Activity with Delirium in Elderly Patients. The American Journey of Geriatric Psychiatry (6:31-41, 1998)

3 Roe et al. Use of Anticholinergic Medication by Older Adults with Dementia. Journal of the American Geriatric Society (50:836-842, 2002)

4 Boustani at al. Impact of Anticholinergics on the Ageing Brain; a review and practical application. Ageing Health (4(3) 311-320, 2008)

5 Fox et al. 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 et al. Cumulative Use of Strong Anticholinergic Medications and Incident Dementia. Journal of the American Medical Association. (175(3): 401-407, 2015)