What is the best approach to manage increased confusion in a 110-year-old female with dementia, currently taking Mirtazapine (mirtazapine) 15mg at bedtime?

Management of Increased Confusion in a 110-Year-Old Female with Dementia on Mirtazapine

Mirtazapine should be discontinued in this 110-year-old female with dementia experiencing increased confusion, as it may be contributing to her symptoms and is not recommended for agitation in dementia.

Assessment of Current Situation

The patient's presentation suggests possible delirium superimposed on dementia, which requires prompt evaluation and intervention. Mirtazapine, while sometimes used in dementia patients for sleep, appetite stimulation, and depression, may be contributing to her confusion through several mechanisms:

• Mirtazapine can cause sedation and cognitive impairment, especially in very elderly patients 1
• Recent high-quality evidence shows mirtazapine is not effective for agitation in dementia and may be associated with increased mortality 2, 3
• Drugs that stimulate appetite (orexigenic drugs) like mirtazapine should not be used in persons with dementia according to current guidelines 1
• Mirtazapine can rarely cause hyponatremia in elderly patients, which can present as confusion 4

Immediate Management Steps

1. Discontinue mirtazapine: The medication should be tapered rather than abruptly stopped

   • Gradual withdrawal over 10-14 days limits withdrawal symptoms 1

2. Rule out delirium: Assess for acute onset, fluctuating course, inattention, and disorganized thinking

   • Delirium is a medical emergency in dementia patients and may be fatal if untreated 1
   • Use a validated tool like the Confusion Assessment Method (CAM) 1

3. Investigate reversible causes of increased confusion:

   • Infection (particularly UTI, pneumonia)
   • Metabolic disturbances (electrolyte abnormalities, dehydration)
   • Medication side effects (review all medications)
   • Pain or discomfort
   • Constipation or urinary retention
   • Sensory deficits 5

Non-Pharmacological Management

Implement these strategies before considering any new medications:

• Establish a predictable daily routine with regular timing for activities, meals, and sleep 1
• Allow the patient to dress in her own clothing and keep familiar possessions 1
• Explain all procedures and activities in simple language 1
• Break complex tasks into simple steps 1
• Use distraction and redirection techniques for problematic behaviors 1
• Ensure proper lighting to reduce confusion and restlessness at night 1
• Reduce environmental stimulation and clutter 1
• Use calendars, clocks, and labels for orientation 1

Alternative Pharmacological Options (If Non-Pharmacological Approaches Fail)

If severe agitation persists after discontinuing mirtazapine and implementing non-pharmacological strategies:

1. For sleep disturbance: Consider trazodone starting at 25 mg at bedtime 5

2. For severe agitation with psychotic features:

   • Low-dose atypical antipsychotic at the lowest effective dose for the shortest duration
   • Quetiapine may be appropriate, especially if Lewy body dementia is suspected 5
   • Monitor closely for side effects and attempt tapering after 4-6 months 1

3. For depression in dementia:

   • SSRIs such as sertraline (25-50 mg/day) or citalopram (10 mg/day) have fewer anticholinergic effects 1
   • Evidence suggests sertraline is better tolerated than mirtazapine in elderly patients 6

Monitoring and Follow-up

• Reassess cognitive status and behavior daily during medication changes
• Document triggers and patterns using ABC (antecedent-behavior-consequences) charting 5
• Involve caregivers in monitoring and implementing non-pharmacological strategies
• Consider referral to geriatric psychiatry for complex management

Caregiver Support and Education

• Educate caregivers on the "three R's" approach: repeat, reassure, and redirect 1
• Provide resources for caregiver support and respite care
• Consider referral to dementia day programs if available

Remember that in very elderly patients with dementia, medications often cause more harm than benefit, and non-pharmacological approaches should be maximized before considering any new medications.