Over the past decade, scientific interest in the itch associated with atopic dermatitis has surged, driving a global expansion of research aimed at unraveling its mechanisms and improving treatment options. A comprehensive analysis involving 2,534 studies published between 2014 and 2023 could offer a detailed map of how this field has evolved.
The body of literature grew rapidly over the 10-year study period, with annual publications rising from 130 in 2014 to 402 by 2023. The increase reflected a widening effort by researchers to better understand the burdens of atopic dermatitis (AD)-related itch and develop targeted therapies.
The United States led global research output, contributing 924 publications with 29,248 citations and an h-index of 88. Germany, Japan, China, and South Korea followed in publication volume, with Germany producing the highest average citations per year at 48.6. Among academic institutions, seven of the top 10 most productive were based in the U.S. Northwestern University led with 148 publications, while the Feinberg School of Medicine recorded the highest total citations at 16,296.
At the study author level, Eric L. Simpson, MD, of Oregon Health & Science University, was the most prolific contributor, authoring 92 publications with 6,738 citations and an h-index of 37. The top 10 study authors accounted for 21.3% of the total research output.
Investigators also identified journals publishing the most research on AD-related itch. Acta Dermato-Venereologica had the highest number of publications, while The Journal of Allergy and Clinical Immunology recorded the most citations. The Journal of the American Academy of Dermatology led in h-index.
Highly cited articles reflected emerging breakthroughs. Studies on the classification of sensory neuron types and the clinical effects of dupilumab in treating moderate-to-severe AD ranked among the most cited. Co-citation analysis grouped the literature into clusters focused on AD pathogenesis, cytokine and sensory neuron pathways, dupilumab treatment, and veterinary diagnostic criteria for canine AD.
The review emphasized the growing role of targeted therapies. Studied treatments included dupilumab, which blocks interleukin (IL)-4 and IL-13; nemolizumab, which targets IL-31 receptor A; and upadacitinib, a selective Janus kinase 1 inhibitor effective among patients unresponsive to other therapies. Crisaborole, a topical phosphodiesterase-4 inhibitor, received attention earlier in the decade but saw a decline in research interest following its market release.
Keyword analysis highlighted evolving research directions. Terms such as "protein-coupled receptor," "JAK inhibitor," "sensory neuron," "quality of life," and "skin barrier" frequently appeared in recent publications, reflecting growing interest in the neuroimmune pathways driving pruritus in AD.
Mechanistic studies consistently identified histamine, type 2 cytokines (IL-4, IL-13, IL-31, TSLP), TRPV1/TRPA1 receptors, mast cells, and sensory neurons as central components of the itch response. Mas-related G-protein–coupled receptor X2 was also implicated in non-immunoglobulin E–mediated mast cell degranulation, expanding the understanding of AD pathophysiology.
The investigators noted limitations of their study, including language restrictions, reliance on a single database, and challenges in linking citation counts to clinical impact. Despite these limitations, the study offered a comprehensive overview of the AD-related itch research landscape over the past decade.
The authors reported no conflicts of interest.
Source: Frontiers in Medicine
