Speaker: ‘Train your eyes’ to assess atopic dermatitis in patients of color

Atopic dermatitis is more prevalent among individuals of color and presents in this population with unique morphologies, according to a speaker at American College of Asthma, Allergy & Immunology Annual Scientific Meeting.

“Atopic dermatitis is a very common disease, but there are a number of variations in epidemiology, probable genetic factors, nuances in clinical presentation [and] approach to treatment and research ... in skin of color populations,” Ama Alexis, MD, clinical assistant professor in the department of pediatrics at NYU Grossman School of Medicine and attending physician in the pediatric allergy clinic at Bellevue Hospital, said during her presentation.

Prevalence, genetic factors

Data suggest that atopic dermatitis is more prevalent among people of color, according to Alexis. For instance, data from the National Survey of Children’s Health showed that African American children were 1.7 times more likely to have atopic dermatitis than their white counterparts, even after adjusting for confounders.

Alexis also presented data showing that atopic dermatitis is more persistent among children of color, whereas it is more transient in their white counterparts. Moreover, persistent disease is associated with poorer overall health status and risk for asthma.

Also, Black and Hispanic children are seen up to three times more frequently at primary care providers or the ED for atopic dermatitis.

In terms of genetic factors, researchers have focused on filaggrin loss-of-function mutations, which are thought to play a role in skin barrier dysfunctions. These mutations occur in about 50% of European Americans and 27% of Asian Americans but are six time less common among African Americans.

Researchers have also reported reduced ceremide levels in Black skin, which can contribute to dryness, as well as increased xerosis and pruritis.

Self-identification of race as African American was associated with twofold higher odds (OR = 2.06; 95% CI, 1.7-2.48) of atopic dermatitis in the GERA cohort, but analyses that looked at genetic ancestry did not replicate these results.

Clinical features

Atopic dermatitis is a heterogenous disease, which is reflected in the variety of clinical manifestations, Alexis said.

Clinicians “must be careful not to underestimate the severity” of atopic dermatitis in people of color when the presentation is not the typical bright red erythema plaques often found in white patients, but rather purple/gray/brown plaques, Alexis said, adding that clinicians may need to “train your eyes” on how to spot erythema in patients of color.

Additional common findings of atopic dermatitis in dark skin types include:

• perifollicular accentuation;
• scattered distinct papules;
• violaceous erythema;
• lichenified, scaly plaques;
• prurigo nodularis; and
• post-inflammatory hypopigmentation.

Treatment

A study by Bell and colleagues published last year in Journal of the National Medical Association showed that Black patients with atopic dermatitis were less likely to receive emerging therapies, such as dupilumab (Dupixent; Sanofi Genzyme, Regeneron) and crisaborole (Eucrisa, Pfizer), but more likely to receive hydrocortisone, according to Alexis.

“Despite the high prevalence of atopic dermatitis in skin of color, there is actually quite little data to support the safety and efficacy of some of our commonly used therapies,” she said.

However, a post-hoc analysis showed that crisaborole improved all the signs and symptoms of atopic dermatitis in all study populations, including induration/papulation and lichenification. Further, the agent had a similar adverse event profile across groups, without evidence of skin discoloration with treatment among Black or Hispanic patients.

Still, a post-hoc analysis of three phase 3 trials of dupilumab showed only some endpoints were met in the subgroup of 128 Black patients, despite meeting all the endpoints in the white and Asian subgroups.

“This is a small sample size which speaks to the need for larger and more diverse studies,” Alexis said, adding that a meta-analysis showed that only 59% of atopic dermatitis trials reported race and ethnicity and only 10.3% considered race or ethnicity when interpreting their results.

To close the gaps in knowledge of clinical outcomes, researchers need to better understand the interplay between genetic and nongenetic factors, Alexis said.

“What are the true drivers in each of these outcomes?” she said. “Is it truly genetic predisposition on one side, or is it due to an interplay of health disparities and social determinants of health — environmental, social and economic — on the other side?”