This new data suggests that while the Skindex-16 can help physicians to better assess severity of disease, greater levels of qualitative as well as quantitative research may be needed.
Skin-related quality of life (SRQL) is linked to disease type and flare state among those with autoimmune bullous diseases (AIBDs), according to new research, and SRQL can inform severity of flares as well as changes in patients’ disease state.1
These findings resulted from a study assessing patients’ Skindex-16 scores as a measure of SRQL in subtypes of AIBDs when patients are in both flare and non-flare states, with the investigators also seeking to assess the Skindex-16’s construct validity.
The research was led by Zachary H. Hopkins, MD, from the University of Utah’s Department of Dermatology in Salt Lake City. Hopkins and colleagues noted that the scarcity of health-related quality of life (HRQL) research in AIBD management, due to the rarity of the disease, unique site involvement, and instrument limitations, necessitates the use of the broadly applicable Skindex-16, despite its validation gaps.2
“Our objective was to describe overall and disease-specific distributions of Skindex-16 scores across AIBDs, stratify these scores across patient-reported flare states, and evaluate available aspects of the construct validity of Skindex-16 in a population of patients with AIBD,” Hopkins and colleagues wrote.
The study’s investigators used a retrospective, cross-sectional design, and their research took place at the University of Utah Health autoimmune dermatology clinic in the period between September 2016 and February 2020.
The work involved 192 total participants with diagnoses of dermatitis herpetiformis, pemphigus, pemphigoid, and linear immunoglobulin A disease.
Each participant had Skindex-16 scores, encounter-linked diagnoses, and self-reported flare status; the statistical analysis phase took place from March 2022 to June 2023.
The research team set their sights on an assessment of Skindex-16 domain scores, with the scores having a range from 0 - 100 (0 suggesting zero impact upon SRQL and 100 suggesting the maximum effect), and individual item scores separated by both disease and flare status.
The team also assessed convergent validity through their examination of Spearman correlations among the participants’ Skindex-16 scores, serologic titers, and other participant-reported outcome measures. Additionally, they looked into floor or ceiling domain scores for Skindex-16, and the team examined structural validity by using confirmatory factor analysis.
Overall, the study ended up using 192 participants in total with 212 visits, where those in a flare state (n=64) reported much higher Skindex-16 domain scores over all categories of disease—including pemphigus, pemphigoid, and dermatitis herpetiformis—versus those in a nonflare state (n=148).
The team added that the Cronbach α was shown to be > 0.80 for all domains as well as AIBDs. They explained that there were moderate or low correlations with desmoglein 1 and bullous pemphigoid 180 titers.
Furthermore, the investigators noted that there were moderate correlations with Patient-Reported Outcomes Measurement Information System Depression scores, and they identified strong correlations with participant-reported severity of disease.
The team also noted that floor domain scores exceeded 20% for nonflare participants, and ceiling domain scores were found to be rare with <10% for all domains. They added that the CFA model fit was poor.
“Routine clinical use of PROMs such as the Skindex-16 can help clinicians better understand disease severity, improving clinician-patient communication and management, but further qualitative and quantitative research is needed,” they wrote.