T-VASI, F-VASI are Reliable Tools to Measure Nonsegmental Vitiligo Progress

A new study found Total Vitiligo Area Scoring Index (T-VASI) and Facial Vitiligo Area Scoring Index (F-VASI) are reliable, valid, and responsive in patients with nonsegmental vitiligo.¹

“These findings agree with those of another study showing that the T-VASI has high inter- and intraobserver reliability, strong test-retest reliability, known-groups validity, and good responsiveness to change in patients with vitiligo,” wrote investigators, led by Khaled Ezzedine, MD, PhD, from the department of dermatology at Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris in France.

Recent 2b data presented at the American Academy of Dermatology (AAD) 2024 Annual Meeting in March showed oral upadacitinib significantly reduced facial and total nonsegmental vitiligo through 52 weeks, as determined through T-VASI and F-VASI.² However, although T-VASI and F-VASI are helpful tools for assessing changes in the vitiligo area, more agreed-upon benchmarks must be needed to interpret how significant improvement is.¹

Clinically meaningful thresholds for these scores have yet to be established. Investigators sought to evaluate the validity and measurement performance of the T-VASI and F-VASI in patients with nonsegmental vitiligo and to identify meaningful change thresholds.

Investigators conducted a secondary analysis of a phase 2 multicenter, double-blind, dose-ranging, randomized clinical trial and embedded qualitative interviews at 35 sites across Canada, France, Japan, and the US from June 16, 2021, to August 29, 2023. Participants had non-segmental vitiligo, with scores of T-VASI ≥ 5 and F-VASI ≥ 0.5 at baseline.

The team used clinician- and patient-reported information to evaluate the psychometric performance of the T-VASI and F-VASI and thresholds for meaningful change. Other than T-VASI and F-VASI scores, they collected data on Vitiligo Noticeability Scale, Total-Patient Global Vitiligo Assessment, Face-Patient Global Vitiligo Assessment, Total-Physician Global Vitiligo Assessment (PhGVA-T), Face-Physician Global Vitiligo Assessment (PhGVA-F), Patient’s Global Impression of Change-Vitiligo, Physician’s Global Impression of Change-Vitiligo, Vitiligo Quality-of-Life Instrument, Dermatology Life Quality Index, and the Hospital Anxiety and Depression Scale. Additionally, qualitative interviews were used to assess content validity and patient perceptions of meaningful re-pigmentation.

The psychometric analysis included 164 participants (mean age: 46 years; 63% female), with more than half of the sample White (69%), followed by Asian (14%), Hispanic (10%), Black (6.7%), multiple races (2.4%), and American Indian/Alaskan Native (0.6%). Moreover, the qualitative analysis included 14 participants (mean age: 48.8 years; 64% female), with most White (86%), followed by 7% Black and 7% Hispanic/Latina.

Participants were randomized to receive either 6, 11, or 22 mg/day of upadacitinib or placebo for 24 weeks. Investigators analyzed the data from March to July 2023.

In patients with clinically stable vitiligo, the intraclass correlation coefficients were 0.98 for T-VASI and 0.99 for F-VASI between baseline and week 4. At baseline and week 24, the correlations were moderate to strong between T-VASI and PhGVA-T, as well as between F-VASI and PhGVA.

The average baseline and week 24 VASI scores reduced with re-pigmentation, and thus increased PhGVA scores. Additionally, the least-square mean VASI scores increased with greater re-pigmentation. The least-square mean VASI scores also differed between patients with improved PhGIC-V scores and no change or worsened V-PhGIC scores.

Furthermore, a multiple anchor approach showed improvements of 30% in T-VASI and 50% in F-VASI scores bringing meaningful re-pigmentation between baseline and week 24. These findings suggest the thresholds of 30% improvement in T-VASI and 50% improvement in F-VASI can bring meaningful change.

“The current study also confirmed that depigmentation, especially in the face and hands, is the primary concern for patients with vitiligo and that the VASI measures concepts and repigmentation that are clinically meaningful to patients,” investigators wrote.

References

1. ^{Ezzedine K, Soliman AM, Camp HS, et al. Psychometric Properties and Meaningful Change Thresholds of the Vitiligo Area Scoring Index. JAMA Dermatol. Published online October 30, 2024. doi:10.1001/jamadermatol.2024.4534}
2. ^{Kunzmann, K. Oral Upadacitinib Significantly Reduces Facial, Total Nonsegmental Vitiligo Through 52 Weeks. HCPLive. March 10, 2024. https://www.hcplive.com/view/oral-upadacitinib-facial-total-nonsegmental-vitiligo-52-weeks. Accessed October 31, 2024.}