in the same studies, according to new data presented at the virtual Skin of Color Update 2020.
“Our findings demonstrate that, though White psoriasis patients may have higher severity in certain body regions such as the trunk, axilla, and groin areas, Latino psoriasis patients have a greater distribution of involvement, particularly in their upper limbs,” reported Alyssa G. Ashbaugh, a third-year medical student at the University of California, Irvine.
The study also found that psoriasis had a greater adverse impact on well-being, as measured with the Dermatology Life Quality Index (DLQI). At entry into the trials from which these patients were drawn, the higher DLQI score, significantly lower quality of life, was nearly two times higher (13.78 vs. 7.31; P = .01) among the Latino patients, compared with White patients.
This is not the first study to show a greater negative impact from psoriasis on Latinos than Whites, according to Ms. Ashbaugh. For example, Latinos had the worse quality of life at baseline by DLQI score than White, Asians, or Black participants in a trial of etanercept that enrolled more than 2000 patients.
In this retrospective chart review, patient characteristics were evaluated in all 21 Latino patients enrolled in psoriasis clinical trials at the University of California, Irvine, in a recent period. They were matched by age and gender to an equal number of White patients participating in the same trials.
The mean age at diagnosis of psoriasis was older in the Latino group than in the White population (42.4 vs. 35.6 years; P = .20), but the difference did not reach statistical significance. The proportion of patients with severe disease on investigator global assessment was also greater but not significantly different in the Latino group, compared with the White group, respectively (42.9% vs. 28.6%; P = .10).
However, differences in the patterns of disease did reach significance. This included a lower mean Psoriasis Assessment Severity Index score of the trunk, axilla, and groin in Latinos (4.74 vs. 9.73; P = .02). But compared with White participants, Latinos had a higher mean percentage of body surface area involvement in the upper limbs (4.78 vs. 1.85; P = .004) and a higher percentage of total body surface area involvement (20.50 vs. 10.03; P = .02).
“While White patients were found to have lived many more years with psoriasis, it is important for future studies to examine whether this is due to earlier onset or delayed diagnosis, given the fact that minorities are less likely to have access to a dermatologist,” reported Ms. Ashbaugh, who performed this work under the guidance of the senior author, Natasha Mesinkovska, MD, PhD, with the department of dermatology, University of California, Irvine.
Overall, the study suggested that body surface coverage and severity is not similarly distributed in Latinos relative to Whites. Although Ms. Ashbaugh conceded that the small sample size and retrospective design of this study are important limitations, she believes that her study, along with previously published studies that suggest psoriasis characteristics may differ meaningfully by race or ethnicity, raises issues that should be explored in future studies designed to confirm differences and whether those differences should affect management.
Other studies have suggested “there are notable differences in the presentation of psoriasis between racial and ethnic groups with the Latino population often presenting to physicians with more severe psoriasis and increased body surface area involvement,” Ms. Ashbaugh noted. Although this appears to be one of the first studies to examine psoriasis characteristics in Latinos relative to Whites, she believes this is an area ripe for further analysis.
Psoriasis “is not a rare occurrence” in non-White populations even if U.S. data suggest that the prevalence in “people of color is lower than that of psoriasis in the U.S. white population,” Amy McMichael, MD, chair of the department of dermatology, Wake Forest Baptist Medical Center, Winston-Salem, N.C., commented in an interview after the meeting. She agreed that it cannot be assumed that psoriasis in skin of color has the same manifestations or responds to treatment in the same way as in White patients.
“Studies have suggested that lesion thickness and, often, extent of disease can be worse in patients of color. Few studies to date have examined the efficacy of treatments and impact of disease in these populations,” she said.
One exception was a study Dr. McMichael and colleagues published last year on the efficacy and safety of the interleukin-17 receptor A antagonist brodalumab for psoriasis in patients of color. The study showed that Black, Latino, and Asian patients participating in the AMAGINE-2 and AMAGINE-3 trials achieved similar outcomes as White participants.
“We published this study because this is one of the first, if not the first, to have enough patients of color to actually draw conclusions about the efficacy of the biologic as well as the patient-reported outcomes,” she explained.
Like the author of the evaluation of Latino patients undertaken at the University of California, Irvine, Dr. McMichael said studies of psoriasis specific to patients of color are needed.
“We cannot assume all patients of color will have the same outcomes as their Caucasian counterparts. It is imperative to include those of color in future psoriasis treatment trials in order to determine the efficacy of new medications,” she added, specifically calling for collection of data on patient-reported outcomes.
Ms. Ashbaugh has no relevant financial relationships to disclose. Dr. McMichael’s disclosures included serving as an investigator and/or consultant for companies that included Allergan, Procter & Gamble, Johnson & Johnson, and Aclaris.