What is the recommended approach to monitoring and managing urticaria using a urticaria activity score (UAS)?

Monitoring and Managing Urticaria Using Urticaria Activity Score (UAS)

The recommended approach for monitoring chronic urticaria is regular assessment using the Urticaria Activity Score over 7 days (UAS7), with patients reassessed within 1-2 weeks of initiating or changing therapy to evaluate treatment response. 1

Understanding the Urticaria Activity Score

The UAS is the gold standard for assessing disease activity in patients with chronic spontaneous urticaria (CSU). It consists of two components:

1. Intensity of pruritus (itch) - scored from 0-3
2. Number of wheals (hives) - scored from 0-3

Two versions of the UAS7 are currently used:

• UAS7: Once-daily documentation over 7 consecutive days
• UAS7TD: Twice-daily documentation over 7 consecutive days

Both versions show comparable clinical properties, but the UAS7 (once-daily) is recommended as it's less burdensome for patients while maintaining similar reliability 2, 3.

Interpreting UAS7 Scores

UAS7 scores correlate with disease severity as follows 2:

• Mild CSU: UAS7 scores of 11-20
• Moderate CSU: UAS7 scores of 16-30
• Severe CSU: UAS7 scores of 27-37

Treatment Algorithm Based on UAS7 Monitoring

1. Initial Assessment: Establish baseline UAS7 score before starting treatment
2. First-line Treatment: Start with second-generation H1-antihistamines 1
3. Reassessment: Evaluate UAS7 after 1-2 weeks 1
4. Treatment Escalation:
   • If inadequate response, increase antihistamine dose up to 4 times standard dose 1
   • Reassess UAS7 after 1-2 weeks
   • If still inadequate, consider adding leukotriene receptor antagonists or advancing to omalizumab or cyclosporine 1, 4

Therapeutic Targets

The recommended therapeutic target for CSU management is:

• Primary target: UAS7 ≤ 6 (well-controlled disease) 5
• Ultimate target: UAS7 = 0 (complete remission) 5

Clinical Response Assessment

When evaluating treatment effectiveness:

• Positive therapeutic response: Reduction to <25% of baseline weekly UAS 4
• Relapse: Return to >75% of baseline weekly UAS 4
• Minimal Important Difference (MID): A change of 9.5-10.5 points in UAS7 represents a clinically meaningful improvement 6, 3

Long-term Monitoring

• Periodically reassess the need for continued therapy using the "as much as needed and as little as possible" approach 1
• Consider step-down protocols in patients with complete disease control (UAS7 = 0) to assess for spontaneous remission 1
• Remember that >50% of patients with chronic urticaria will have resolution or improvement within one year, though patients with both wheals and angioedema tend to have poorer prognosis 1

Important Considerations

• UAS7 is a patient-reported outcome that empowers patients to participate in their care
• Regular monitoring with UAS7 helps identify treatment non-responders early
• The treat-to-target approach using UAS7 provides objective goals for therapy adjustment
• Document UAS7 scores at each visit to track disease progression and treatment response over time

Pitfalls to Avoid

• Don't rely solely on in-clinic assessment; the 7-day documentation provides a more accurate picture of disease fluctuation
• Avoid continuing ineffective treatments without proper UAS7 reassessment
• Ensure proper patient education on how to accurately score their symptoms to maintain reliability of the UAS7
• Don't delay treatment escalation when UAS7 scores indicate inadequate control