What is a suitable delirium screen for an elderly patient during a primary care home visit?

Delirium Screening in Primary Care Home Visits

For primary care home visits, use the Confusion Assessment Method (CAM), which takes less than 5 minutes to complete and has excellent diagnostic accuracy (sensitivity 95-100%, specificity 90-95%) without requiring specialized training. 1, 2

Recommended Screening Tool: The Confusion Assessment Method (CAM)

The CAM is the most appropriate tool for home visits because it:

• Can be completed in under 5 minutes 2
• Requires no special training for administration 3
• Has been validated specifically for non-psychiatric clinicians 2
• Works well in non-ICU settings 1, 4
• Has high sensitivity (93-100%) and specificity (90-95%) across multiple validation studies 2, 3

The CAM Algorithm (4 Key Features)

A diagnosis of delirium requires BOTH features 1 AND 2, PLUS either feature 3 OR 4: 2

1. Acute onset and fluctuating course: Ask family/caregivers if there was a sudden change in mental status that varies throughout the day 4

2. Inattention: Patient has difficulty focusing attention, is easily distractible, or has trouble keeping track of conversation 2

3. Disorganized thinking: Conversation is rambling, irrelevant, unclear, or illogical flow of ideas 2

4. Altered level of consciousness: Any state other than alert (vigilant, lethargic, stuporous, or comatose) 2

Alternative Tool: The 4AT

If you need an even simpler option, consider the 4AT (4 'A's Test), which takes 2-3 minutes and has comparable accuracy (sensitivity 76%, specificity 94%): 5, 3

The 4AT assesses:

• Arousal: Level of alertness 5
• Attention: Ability to focus (e.g., reciting months backwards) 5
• Abbreviated Mental Test-4: Brief cognitive questions 5
• Acute change: Sudden change in mental status 5

A score >3 on the 4AT (scale 0-12) indicates positive screening for delirium. 5, 3

Critical Information to Obtain During Home Visit

Before applying the screening tool, gather collateral history from family/caregivers about: 4

• Baseline cognitive function and any pre-existing dementia 4
• Exact timeline of symptom onset (when was patient last at baseline) 6
• Recent medication changes, especially anticholinergics, sedatives, opioids, or antipsychotics 6, 4
• Recent falls, head trauma, or loss of consciousness 4
• Alcohol use and risk of withdrawal 4

Common Pitfalls to Avoid

Do not mistake hypoactive delirium for depression or fatigue - this is the most commonly missed presentation and represents the majority of delirium cases in elderly patients 4

Do not attribute acute confusion to pre-existing dementia without screening for delirium - delirium commonly occurs superimposed on dementia and represents a medical emergency requiring investigation 4

Do not rely on clinical judgment alone - without validated screening tools, clinicians fail to recognize delirium in the majority of cases 4

When CAM is Positive: Immediate Actions

If delirium is detected, this is a medical emergency requiring: 6, 4

• Check blood glucose immediately to rule out hypoglycemia 6
• Assess vital signs including oxygen saturation 6
• Review all medications, particularly recent additions 6, 4
• Consider urgent evaluation for infection (urinary tract infection and pneumonia are most common precipitants) 4
• Arrange for comprehensive medical evaluation including laboratory testing and possible neuroimaging if focal deficits present 6, 4

Special Considerations for Home Visits

The CAM performs well even in patients with pre-existing dementia (sensitivity 96%, specificity 86% in dementia patients), making it ideal for elderly home-bound patients 7

Mental status fluctuates substantially throughout the day in delirium, so if initial assessment is negative but suspicion remains high, consider reassessment at a different time 4