Clinical Uncertainty More Likely in Black Patients Seeing Dermatologists for Psoriasis

Junko Takeshita, MD, PhD, MSCE
Credit: Penn Medicine

Data from a new study is calling attention to disparities in the management of psoriasis for patients of color.

An analysis of data from more than 10,000 patients with psoriasis, results suggest non-Hispanic Black patients were more than twice as likely to undergo a skin biopsy for psoriasis relative to their non-Hispanic White counterparts.¹

“In this cross-sectional study of patients with psoriasis, we found racial differences in the frequency of skin biopsies for psoriasis that suggest diagnostic uncertainty in making a clinical diagnosis of psoriasis that disproportionately affects Black individuals,” wrote investigators.¹ “This diagnostic uncertainty may, in turn, contribute to diagnostic and treatment delays that could be important drivers of the greater objective and subjective disease burden that has been observed among Black adults with psoriasis compared with White adults with psoriasis.”

A lack of representation remains the elephant in the room for many conversations in dermatology, with historic disparities plaguing trial representation, not unlike other fields in medicine, and trickling down into clinical care and guidelines. Citing a lack of definitive research on how uncertainty in diagnosis of psoriasis among individuals with skin of color, a team of investigators led by Junko Takeshita, MD, PhD, MSCE, of the Perelman School of Medicine at the University of Pennsylvania, sought to describe how this translates to clinical practice.^1,2

With this in mind, investigators designed their study to determine the frequency of skin biopsy, as a marker of diagnostic uncertainty, among patients with psoriasis seen at outpatient dermatology clinicians within the University of Pennsylvania Health System. For inclusion in the study, patients were required to be at least 18 years of age and have at least 1 outpatient dermatology encounter with an ICD-9 or ICD-10 code for psoriasis between January 1, 20201 and December 31, 2019.¹

The primary outcome of interest for the study was the performance of a skin biopsy for psoriasis. Investigators used a combined race and ethnicity variable based on electronic medical record documentation as the primary independent variable for their analyses. For the purpose of analysis, the likelihood of a skin biopsy for psoriasis was estimated using multivariable logistic regression and expressed as odds ratios (ORs).¹

Investigators identified 10,008 patients meeting the inclusion criteria for the study. The overall study cohort had a mean age of 55.71 (SD, 16.8) years, 56.0% were female, 70.6% were non-Hispanic White, 13.1% were non-Hispanic Black, 4.9% were Asian or Other Pacific Islander, 3.2% were Hispanic, 3.7% were classified as Other, and 4.5% were of unknown race or ethnicity.¹

Overall, 4.8% of patients received a skin biopsy for psoriasis. Initial analysis indicated biopsies were most common for non-Hispanic Black patients (9.8%) followed by Asian or Other Pacific Islander patients (4.7%), non-Hispanic White patients (4.1%), patients of unknown race (4.0%), Hispanic patients (3.7%), and patients of other races.¹

Further analyses adjusted for sociodemographic and health care utilization factors suggested non-Hispanic Black patients were more likely to receive a skin biopsy for psoriasis than their non-Hispanic White counterparts (OR, 2.03; 95% CI, 1.54 to 2.65; P <.001). Investigators pointed out these results were consistent in sensitivity analyses using both narrower and broader definitions of a skin biopsy for psoriasis. Of note, an increased likelihood of skin biopsy, relative to non-Hispanic White counterparts, was increased for Asian patients, but this failed to reach statistical significance (OR, 1.42; 95% CI, 0.88 to 2.18; P = .12).¹

Investigators called attention to multiple limitations within their study. These limitations included the potential that the urban academic practice’s patient population may not be representative of other practices or settings and the uncertainty in the validity of algorithms used to identify skin biopsies.¹

“These findings add to the limited literature on diagnostic uncertainty by patient race and ethnicity in the clinical setting; they confirm similar findings from a small prior study and provide important granularity on the association between specific racial and ethnic groups and the likelihood of skin biopsy for psoriasis,” investigators added.¹

References:

1. Ahmed F, Fitzsimmons R, Chu EY, Shin DB, Takeshita J. Frequency of Skin Biopsies for Psoriasis by Race and Ethnicity. JAMA Dermatol. Published online August 07, 2024. doi:10.1001/jamadermatol.2024.2554
2. Smith T. Crisis point: Improving diversity in dermatology. HCP Live. July 29, 2024. Accessed August 7, 2024. https://www.hcplive.com/view/crisis-point-improving-diversity-in-dermatology.