How do I assess a patient using the Abnormal Involuntary Movement Scale (AIMS)?

How to Assess a Patient Using the Abnormal Involuntary Movement Scale (AIMS)

The Abnormal Involuntary Movement Scale (AIMS) is a standardized assessment tool used to detect and monitor tardive dyskinesia in patients taking antipsychotic medications, consisting of 12 items with items 1-7 specifically assessing the severity of involuntary movements across different body regions.

AIMS Assessment Procedure

Step 1: Patient Preparation

• Seat the patient in a firm, armless chair
• Ask the patient to remove shoes and socks
• Explain that you will be observing their movements

Step 2: Observation of Movements at Rest

• Observe the patient unobtrusively while they are sitting at rest
• Note any abnormal movements in the following areas:
  • Facial and oral movements
  • Extremity movements
  • Trunk movements

Step 3: Specific Examination Tasks

Have the patient perform the following tasks while you observe for abnormal movements:

1. Facial/Oral Examination:

   • Ask patient to open mouth
   • Examine tongue at rest within mouth
   • Ask patient to protrude tongue
   • Ask patient to tap thumb against each finger rapidly for 10-15 seconds (separately with right and left hands)
   • Ask patient to extend both arms in front with palms down
   • Ask patient to open and close mouth

2. Extremity Examination:

   • Ask patient to extend both arms in front with palms down
   • Ask patient to pronate and supinate hands
   • Ask patient to flex and extend fingers
   • Have patient stand up
   • Ask patient to walk a few paces, turn, and walk back to chair

Step 4: Scoring the 7 Movement Items

Score each of the following 7 items on a scale of 0-4:

• 0 = None
• 1 = Minimal (may be normal)
• 2 = Mild
• 3 = Moderate
• 4 = Severe

1. Facial and Oral Movements:

   • Item 1: Muscles of facial expression (e.g., movements of forehead, eyebrows, periorbital area, cheeks)
   • Item 2: Lips and perioral area (e.g., puckering, pouting, smacking)
   • Item 3: Jaw (e.g., biting, clenching, chewing, mouth opening, lateral movement)
   • Item 4: Tongue (rate only increase in movement both in and out of mouth, NOT inability to sustain movement)

2. Extremity Movements:

   • Item 5: Upper limbs (arms, wrists, hands, fingers) - include choreic movements and athetoid movements
   • Item 6: Lower limbs (legs, knees, ankles, toes) - e.g., lateral knee movement, foot tapping, heel dropping, foot squirming, inversion and eversion of foot

3. Trunk Movements:

   • Item 7: Neck, shoulders, hips (e.g., rocking, twisting, squirming, pelvic gyrations)

Step 5: Global Judgment Items (Items 8-10)

Score these items on the same 0-4 scale:

• Item 8: Severity of abnormal movements overall
• Item 9: Incapacitation due to abnormal movements
• Item 10: Patient's awareness of abnormal movements (0=no awareness, 4=aware and severely distressed)

Step 6: Dental Status (Items 11-12)

Record the patient's dental status:

• Item 11: Current problems with teeth and/or dentures (Yes/No)
• Item 12: Are dentures usually worn? (Yes/No)

Interpretation and Documentation

The AIMS total dyskinesia score is calculated by summing items 1-7, with scores ranging from 0 to 28 1. A decrease in score indicates improvement.

Tardive dyskinesia is typically defined as at least mild symptoms (score ≥2) in two or more anatomical areas, or moderate or greater symptoms (score ≥3) in one or more areas 2.

Important Clinical Considerations

• Regular screening is essential: Perform AIMS assessments at baseline and periodically for all patients on antipsychotic medications 3
• Experience matters: Experienced raters generally have higher levels of agreement and more consistent scores over time 4
• Differentiate movement dimensions: Consider quality, frequency, and amplitude of movements, though these are not explicitly captured in the current AIMS 4
• Training improves accuracy: Implementation of formal AIMS training sessions significantly improves documentation compliance 5
• Documentation: Record AIMS scores in the patient's chart to track changes over time and guide treatment decisions

Common Pitfalls to Avoid

1. Inadequate observation time: Ensure sufficient time to observe the patient both at rest and during specific tasks
2. Failure to distinguish between different movement disorders: Tardive dyskinesia must be differentiated from other movement disorders like akathisia, dystonia, or Parkinson's disease
3. Inconsistent examination conditions: Try to assess patients under similar conditions each time (time of day, medication timing)
4. Not accounting for dental status: Poor-fitting dentures or dental problems can mimic oral dyskinesias
5. Missing subtle movements: Pay close attention to mild movements that may indicate early tardive dyskinesia

By following this structured approach to AIMS assessment, clinicians can effectively detect, monitor, and document tardive dyskinesia in patients taking antipsychotic medications, enabling early intervention and appropriate management.