Exploring anticholinergic burden in older adults in the acute hospital setting

Anticholinergic drugs are used to treat conditions such as Parkinson's disease, depression, nausea and vomiting, chronic obstructive pumonary disease (COPD), and pain. They work by blocking acetylcholine, a neurotransmitter found throughout the parasympathetic nervous system, which exerts its effects on the muscles via the motor neurons (Chancellor et al, 2012). In certain conditions, such as bladder instability or gastrointestinal disturbance, some drugs are prescribed specifically for their anticholinergic properties. Acetylcholine inhibits smooth muscle function in the gastrointestinal and urinary tracts, and in the lungs. An example of anticholinergic effects in the peripheral nervous system is reduced secretions, which can cause slowed gastrointestinal motility. This can lead to constipation, urinary retention, increased risk of infection, blurred vision, and increased heart rate. Anticholinergic effects on the central nervous system include sedation, confusion, poor concentration, agitation, hallucinations and cognitive decline (Tune, 2001). In the brain, acetylcholine is one of the chemicals that enable messages to be passed between neurons. Acetylcholine is thought to be one of the key neurotransmitters involved in memory and learning, and is much reduced in Alzheimer's disease. Older adults are more susceptible to anticholinergic effects as there is a reduction in the acetylcholine neurones and receptors in the brain with age (Pasina et al, 2013).