Should Cholinesterase Inhibitors (ChEI) +/- memantine be recommended for very old patients in a long-term care (LTC) facility with moderate vascular dementia and behavioral disturbances?

Cholinesterase Inhibitors and Memantine for Very Elderly Patients with Moderate Vascular Dementia and Behavioral Disturbances in LTC

Cholinesterase inhibitors (ChEIs) and memantine are not recommended for very elderly patients in long-term care facilities with moderate vascular dementia and behavioral disturbances due to limited efficacy and potential adverse effects in this vulnerable population. 1

Efficacy Considerations in Vascular Dementia

• Evidence for ChEIs in vascular dementia shows only small clinical benefits that may not be clinically meaningful:

  • Memantine demonstrates modest cognitive improvement of 2.15 ADAS-Cog points in vascular dementia 2
  • However, there is probably no difference in global clinical rating (0.03 CIBIC+ points) and likely no difference in activities of daily living 2

• For behavioral symptoms specifically:

  • Memantine shows only a small clinical benefit for behavioral measures in vascular dementia (0.47 NOSGER points) 2
  • While memantine may reduce agitation as an adverse event, it has not demonstrated significant benefit as a treatment for existing agitation 2

Safety Concerns in Very Elderly LTC Patients

• Cholinesterase inhibitors carry significant risks in frail elderly populations:

  • Two to fivefold increased risk for gastrointestinal, neurological, and cardiovascular side effects 1
  • Most serious adverse effects include weight loss, debility, and syncope 1
  • Patients over 85 years have double the risk of adverse events compared to younger patients 1

• Memantine's common adverse events include:

  • Dizziness (6.1% vs 3.9% for placebo) 2
  • Headache (5.5% vs 4.3% for placebo) 2
  • Confusion and constipation 3

Specific Considerations for LTC Setting

• The institutional nature of LTC facilities and the COVID-19 pandemic add complexity to dementia care 4
• Social distancing regulations and visiting restrictions may already compromise social contacts and meaningful activities for residents with dementia 4
• Non-pharmacological approaches for behavioral symptoms (such as distraction, engagement in activities) may be more difficult to implement in LTC settings due to staffing and resource constraints 4

Duration of Treatment Concerns

• The efficacy of ChEI treatment appears to wane over time, with minimal benefit seen after 1 year 1
• Long-term studies of memantine are limited, with most trials reporting outcomes only up to 6 months 2
• For very elderly patients with moderate vascular dementia, the limited duration of benefit must be weighed against ongoing risk of adverse effects

Alternative Approaches for Behavioral Symptoms

• Non-pharmacological interventions should be prioritized:
  • Educational components designed to increase caregiver skills show consistent small benefits on caregiver burden and depression outcomes 4
  • Cognitive stimulation with or without cognitive training may be reasonable for patients with cognitive impairment 4

Deprescribing Considerations

• The Canadian Consensus Conference on Diagnosis and Treatment of Dementia recommends:
  • ChEIs and memantine should be deprescribed when no clinically meaningful benefit was observed at any time during treatment 4
  • Deprescribing is particularly indicated when the individual has severe dementia or develops intolerable side effects 4
  • Gradual dose reduction is recommended, with reduction by 50% every 4 weeks 4

In conclusion, while memantine and ChEIs show some modest benefits in certain dementia populations, the risk-benefit ratio for very elderly patients with moderate vascular dementia in LTC settings favors avoiding these medications. Focus should instead be placed on non-pharmacological approaches to manage behavioral disturbances, with careful consideration of the individual's quality of life and overall burden of medication.