Patients With Moderate to Severe Alopecia Areata Exhibit Higher Risk of Developing Atopic Dermatitis

Alopecia universalis | Image credit: DermNet

A recent retrospective analysis evaluated the real-world prevalence, incidence, and relative risk of comorbid moderate to severe atopic dermatitis (AD) among patients with alopecia areata (AA). Overall, patients with moderate to severe AA had an increased risk of developing atopic dermatitis compared to patients with mild AA. Mostaghimi et al’s late-breaking data was presented at the 2024 Revolutionizing Alopecia Areata, Vitiligo, and Eczema Conference in Chicago, Illinois, held June 8 –10.¹

In their review, Mostaghimi et al noted that previous studies^2,3 have also identified that patients with AA have an increased risk of developing AD compared to patients without AA, yet the “real-world prevalence and incidence of moderate to severe AD in patients with AA are not well characterized.”¹ As Ly et al noted, “In recent years, many studies have provided new evidence on comorbid diseases present in patients with AA. However, some studies have conflicting results, and analyses conducting a comprehensive approach are lacking.”³

Methods

Using US databases, Mostaghimi et al’s analysis included patients aged 12 years and older who received a diagnosis of AA between January 1, 2017, and July 31, 2023, and who had been continuously enrolled in a health insurance plan for 5 years or more before the date of their first diagnosis of AA. Additionally, patients were required to have 6 months or more of continuous health insurance coverage after the initial diagnosis date to evaluate the severity of their AA.

Mostaghimi et al evaluated the prevalence of AD among eligible patients 5 years before the initial AA diagnosis date, as well as over a longer period that included patients with one or more diagnoses of AD anytime from January 1, 2007, to the initial diagnosis date, regardless of health insurance. The incidence of AD was evaluated 7 months after the initial AA diagnosis date through the time of an AD diagnosis or the end of continuous health insurance coverage.

In the analysis, moderate to severe AA was defined as a diagnosis of alopecia universalis (AU) or alopecia totalis (AT), or “prescription claims for any systemic immunomodulators, oral corticosteroids, nonsteroidal systemic agents, or phototherapy within 6 months after index date.” Very severe AA was defined as a diagnosis of AU or AT. Any prevalence of AD was defined as one or more inpatient or 2 or more outpatient claims with a diagnosis code for AD or other AD-related skin conditions. Moderate to severe AD was defined as the previous AD criteria plus one of the following: at least one use of dupilumab; at least 2 uses of high-potency topical corticosteroids (TCS) or systemic immunosuppressants; or at least 3 uses of medium-potency TCS, topical tacrolimus, phototherapy, or oral/parenteral corticosteroids.

Results

Hand atopic dermatitis | Image credit: DermNet

Based on the database search, 429,903 patients with AA were identified. Of the total patients, 10,863 (2.5%) met the eligibility criteria with at least 5 years of continuous health insurance coverage, and 9507 (2.2%) completed at least 6 months of follow-up after initial diagnosis. The majority of eligible patients were women (63.0%) with a mean age of 40.4 years and a mean Charlson Comorbidity Index of 0.7.

In the prevalence cohort (n=9507), 7087 (74.5%) patients had mild AA, 2420 (25.5%) patients had moderate to severe AA, and 491 (5.2%) had very severe AA. In the incidence cohort (n=8137), 6160 (75.7%) patients had mild AA, 1977 (24.3%) had moderate to severe AA, and 416 (5.1%) had very severe AA.

Regarding all eligible patients with AA, the prevalence of AD within 5 years of diagnosis was 3.1% for any AD and 2.3% for moderate to severe AD. For patients with moderate to severe AA, the prevalence of AD within 5 years of diagnosis was 4.8% for any AD and 4.2% for moderate to severe AD. For patients with very severe AA, the prevalence of AD within 5 years of diagnosis was 3.5% for any AD and 3.3% for moderate to severe AD. The prevalence of any AD at any time before diagnosis among all eligible patients with AA and moderate to severe AA was 11.9% and 14.6%, respectively. Overall, patients with moderate to severe and very severe AA had a higher prevalence of moderate to severe atopic dermatitis than patients with mild AA.

The incidence rates of AD for patients with mild AA was 4/1000 patient years (PYs), 7/1000 PYs for patients with moderate to severe AA, and 5.9/1000 PYs for patients with very severe AA. Overall, the risk of developing AD was higher in patients with moderate to severe AA compared to patients with mild AA.

“It may be beneficial for health care professionals treating patients with moderate-to-severe alopecia areata to also consider the potential presence of atopic dermatitis in these patients and optimize treatment decisions accordingly,” concluded Mostaghimi et al.

References

1. Mostaghimi A, Armstrong A, Grada A, et al. Prevalence and incidence of atopic dermatitis in patients with alopecia areata in the United States: a population-based study. Poster presented at: 2024 Revolutionizing Alopecia Areata, Vitiligo, and Eczema Conference; June 8-10, 2024; Chicago, IL
2. Lee S, Lee H, Lee CH, Lee WS. Comorbidities in alopecia areata: a systematic review and meta-analysis. J Am Acad Dermatol. 2019;80(2):466-477.e16. doi:10.1016/j.jaad.2018.07.013
3. Ly S, Manjaly P, Kamal K, et al. Comorbid conditions associated with alopecia areata: a systematic review and meta-analysis. Am J Clin Dermatol. 2023;24(6):875-893. doi:10.1007/s40257-023-00805-4