Zarqa Ali, MD, PhD

Credit: LinkedIn

Three major clusters of atopic dermatitis involvement—the legs and genital areas, the upper body, and the hands and feet areas—have been differentiated as 3 different subgroups of patients with distinctive characteristics, according to recent findings.¹

As a heterogeneous disease, atopic dermatitis can be categorized into several different phenotypes based on characteristics such as disease severity, age of disease onset, and clinical or morphological features.²

The investigators of this new study, led by Zarqa Ali, MD, PhD, from the Department of Dermato-Venereology and Wound Healing Centre at Copenhagen University Hospital Bispebjerg in Denmark, sought to identify clusters of bodily regions affected by eczema in adult patients.

Additionally, Ali and colleagues sought to “determine characteristics of these clusters based on age of onset and other atopic diseases, and to explore patterns of subjective and clinical changes, based on photographic assessments of AD lesions, in disease activity over time.”

Background and Findings

The investigators examined data from an 8-week decentralized feasibility study involving patients with atopic dermatitis. The study was conducted to determine if a siteless trial could recruit participants nationwide, maintain high adherence, and minimize dropouts.

Patients with atopic dermatitis were recruited by the research team online through the use of social media advertisements.

Those with the condition who had been recruited were included in the research if they met the UK Diagnostic Criteria for Atopic Dermatitis, were 18 years or older, and had at least 1 visible lesion from their condition confirmed by board-certified dermatologists based on a photograph taken by the patient on the patients’ own smartphones.

Throughout the study, the investigators had the participants finish a questionnaire about affected body areas and self-report the severity of their atopic dermatitis.

The Patient-Oriented Eczema Measure (POEM) and SCORing Atopic Dermatitis (SCORAD) were used to evaluate disease severity based on weekly compilations of POEM and photographs taken by participants.

The research team recruited 55 participants, with 53 of them completing the initial questionnaire. The average POEM score for those recruited for the research was found to be 14.5, with a standard deviation of 5.6.

Through principal component analysis, the study identified three distinct clusters. Cluster 1 exhibited AD primarily on the legs (shins, knees) and genitals, while Cluster 2 showed involvement of the upper body, and Cluster 3 displayed AD on the hands and feet.

Notably, the investigators found that Cluster 1 had a lower average POEM score (11.12, SD: 5.3) compared to Clusters 2 (12.64, SD: 4.5) and 3 (15.98, SD: 4.7), with a statistically significant difference (P = 0.007).

Additionally, the research team noted that Cluster 1 was shown to have the highest average age of disease onset (9.5 years compared to 2.5 and 4.7 years in Clusters 2 and 3, respectively. P = 0.02). It also was shown to have the lowest proportion of participants with asthma/allergy (47% compared to 82% and 90% in Clusters 2 and 3, respectively; P = 0.01).

“Understanding characteristics and longitudinal change in AD-specific patient clusters is important to provide the best counseling and treatment,” they wrote.

References

1. ^{Ali Z, Anderson K, Andersen AD, Dahiya P, Zibert JR, Thomsen SF. Assessing anatomical distribution of atopic dermatitis identifies a cluster of patients with late onset and low risk of asthma and allergy: An observational study. Health Sci Rep. 2023 May 4;6(5):e1219. doi: 10.1002/hsr2.1219. PMID: 37152231; PMCID: PMC10158772.}
2. ^{Pugliarello S, Cozzi A, Gisondi P, Girolomoni G. Phenotypes of atopic dermatitis. J Dtsch Dermatol Ges. 2011; 9(1): 12- 20.}