From the Guidelines
Anticholinergic agents should be avoided in patients with Lewy body dementia (LBD) due to their potential to significantly worsen cognitive function and exacerbate neuropsychiatric symptoms. According to the recommendations of the 5th Canadian Consensus Conference on the Diagnosis and Treatment of Dementia 1, medications with anticholinergic properties, such as trihexyphenidyl, benztropine, oxybutynin, diphenhydramine, tricyclic antidepressants, and certain antipsychotics, should be used with caution in patients with dementia.
Key Considerations
- LBD patients are particularly sensitive to the effects of anticholinergic agents due to their underlying cholinergic deficit and disrupted neurotransmitter systems.
- Cholinesterase inhibitors, such as rivastigmine, donepezil, or galantamine, are recommended as they increase acetylcholine levels and can improve cognition and behavioral symptoms in LBD patients.
- When treating psychosis in LBD, low-dose quetiapine or clozapine may be used cautiously, as they have lower anticholinergic properties than other antipsychotics.
- It is essential to review a patient's complete medication list to identify and discontinue hidden anticholinergic agents that might be contributing to cognitive decline or behavioral disturbances.
Deprescription Guidelines
The guidelines suggest that cholinesterase inhibitors should not be discontinued in individuals who currently have clinically meaningful psychotic symptoms, agitation, or aggression until these symptoms have stabilized, unless these symptoms appear to have been worsened by the initiation of a ChEI or an increase in ChEI dose 1. Additionally, individuals who have had a clinically meaningful reduction in neuropsychiatric symptoms with cognitive enhancers should continue to be treated with the cognitive enhancer even if there is evidence of cognitive and functional decline 1.
Treatment Approach
In summary, the use of anticholinergic agents in LBD should be avoided, and cholinesterase inhibitors should be considered as a treatment option. A thorough review of the patient's medication list and careful consideration of the potential benefits and risks of each medication are essential to optimize treatment outcomes and minimize adverse effects in patients with LBD.
From the Research
Anticholinergic Agents in Lewy Body Dementia
- Anticholinergic drugs often induce delirium in demented patients and therefore should be avoided 2
- The use of anticholinergic agents is associated with physical and cognitive decline and increased mortality in patients with dementia with Lewy bodies (DLB) 3
- There is no evidence to suggest that anticholinergic agents are effective in managing the cognitive and behavioral symptoms of DLB
Alternative Treatments for DLB
- Cholinesterase inhibitors, such as rivastigmine, galantamine, and donepezil, have been shown to be effective in managing the cognitive and behavioral symptoms of DLB 4, 5, 6
- Memantine may also be effective in improving clinical global impression of change in patients with mild to moderate DLB 4
- Levodopa can be used to treat parkinsonism in DLB patients, but the dose is often limited due to the risk of agitation or worsening of visual hallucinations 4, 2
Safety and Tolerability of Cholinesterase Inhibitors
- Cholinesterase inhibitors are generally well-tolerated, but may cause adverse events such as tremor and parkinsonian symptoms 5
- Rivastigmine may be associated with a higher risk of adverse events compared to donepezil 5
- The use of cholinesterase inhibitors may be associated with a lower risk of mortality compared to placebo 5