Alopecia Areata Research Increases Over the Last 2 Decades

A bibliometric analysis reveals a significant increase in research on alopecia areata (AA) treatment over the past 2 decades, with a focus on identifying effective therapies and understanding underlying mechanisms of the condition. | Image Credit: tadamichi - stock.adobe.com

Research into alopecia areata (AA) treatment has grown substantially over the last 20 years, with a focus on emerging therapies like Janus kinase (JAK) inhibitors and platelet-rich plasma (PRP), according to a bibliometric analysis published in Dermatology.¹

Alopecia is typically classified among 3 subtypes: patchy, alopecia totalis, or alopecia universalis. Patients with patchy AA typically have 1 or more coin-sized, round or oval, patches on the scalp or other areas on the body.² Sometimes, patchy AA can convert to alopecia totalis, hair loss across the entire scalp, or universalis, hair loss across the entire body.

Patients with AA are impacted both physically and mentally but there is yet to be a single method that can safely, efficiently, and permanently cure the condition.

Dermoscopy is a noninvasive method that allows the in vivo evaluation of colors and microstructures of the epidermis, the dermoepidermal junction, and the papillary dermis not visible to the naked eye.³ Common dermascopic findings in patients with AA include yellow dots (84.1%), vellus hairs (62.6%), black dots (48.4%), exclamation mark hairs (30.9%), and broken hairs (9.5%).¹ 

“Conducting a bibliometric analysis of the literature on AA treatment over the past 20 years could provide valuable insights into the current state of research in this field,” the study authors stated.

Experts conducted a literature search on the Web of Science (WoS) database in May 2023 and searched for publications from 2003 through 2022.

Publication Phases

The database search yielded 1323 studies on AA treatment from the past 2 decades. The study period was divided into 3 phases: 2003 to 2008, 2009 to 2018, and 2019 to 2023.

The first phase included about 30 articles per year and research on AA treatment was very limited. By the third phase, researchers noticed a significant increase in published articles each year.

Geographic Analysis

Publications stemmed across 65 countries and 1603 institutions, with the top 10 countries distributed across North America, Asia, and Europe.

The largest number of publications were found in the US (n = 443), followed by China (n = 106). The majority of articles on AA treatment were published at the University of Miami (n = 42), Columbia University (n = 34), and Icahn School of Medicine at Mount Sinai (n = 31).

Citation Evaluation

Among the 358 journals that published research on AA treatment, Dermatologic Therapy was the most prolific with 68 studies, followed by the Journal of the American Academy of Dermatology with 61. In terms of impact, the Journal of the American Academy of Dermatology led with an impact factor of 15.49, followed by the British Journal of Dermatology at 11.11 among the top 10 journals.

The Journal of the American Academy of Dermatology was the most frequently cited journal with 5363 co-citations, followed by the British Journal of Dermatology at 3279.

Among co-cited journals, the New England Journal of Medicine had the highest impact factor of 176.08, followed by the Journal of the American Academy of Dermatology at 15.49.

Contributions

A total of 5169 authors contributed to the research on AA treatment. The top 10 most prolific authors collectively published 162 articles on the subject, accounting for more than 10% of all included studies.

Over the past 2 decades, research on AA treatment garnered 35,319 citations. A review of the top 10 most cited references revealed a predominance of review articles and guidelines rather than original research with experimental data.

Keywords

Citation bursts are often included in references that have been cited consistently and usually in a certain field over time. Tumor necrosis factor (7.75) was the strongest citation burst revealed in the analysis.

The newest research hotspots and research directions included tofacitinib, variant, PRP, epidemiology, and lichen planopilari.

Common keywords focused on JAK inhibitors, including specific medications like ruxolitinib and tofacitinib. Other terms centered on basic research aspects of AA treatment, such as double-blind studies and T cell involvement.

Keywords related to clinical diagnosis and classification encompass frontal fibrotic alopecia and scalp conditions. Treatment and management keywords included curative approaches, treatment regimens, and corticosteroids like triamcinolone. Finally, keywords for the 2020-2022 period emphasized patient quality of life, laser therapies, immune system components, and cytotoxic T cells.

Limitations

The study primarily relied on articles present in the WoS database which the authors reported as a limitation because this may not represent all relevant publications or provide a comprehensive overview. Additionally, the search period was limited from 2003 to 2022, excluding articles before 2003 or after 2022.

“Currently, JAK inhibitors, PRP, and variants are the frontiers of research in this field and are currently emerging,” the study authors concluded.

References

1. Luo W, Shen G, Yang L, Zhu X. A bibliometrics of the treatment of alopecia areata in the past twenty years. Dermatology. (2024) 240 (1): 42–58. doi:10.1159/000535043
2. Alopecia areata types. National Alopecia Areata Foundation. Accessed August 16, 2024. https://www.naaf.org/alopecia-areata/types-of-alopecia-areata/#:~:text=Alopecia%20areata%20(patchy)%20causes%20one
3. Dermoscopy: overview, technical procedures and equipment, color. eMedicine. March 10, 2023. Accessed August 16, 2024. https://emedicine.medscape.com/article/1130783-overview?form=fpf