Progress needed in treating patients with skin of color and psoriasis

Welcome to this special edition of Healio Psoriatic Disease, which focusses on the management of psoriasis in patients with skin of color, coinciding with Black History Month.

In 1966, Dr. Martin Luther King Jr. famously stated, “Of all the forms of inequality, injustice in health care is the most shocking and inhumane.” The Institute of Medicine has defined a health care disparity as a “difference in treatment or access not justified by the differences in health status or preferences of the groups.” We hope this issue calls attention to aspects of psoriatic disease that disproportionately affect patients with skin of color so that we may achieve better outcomes for all our patients.

The work of understanding how psoriatic disease affects patients with skin of color is just beginning. Early in my career, I was frustrated that psoriasis was described as rare in African Americans when this did not match my clinical experience. In 2005, I published the first United States population-based estimate of the prevalence of psoriasis in African Americans, debunking this dogma. We found that although psoriasis is less common in African Americans (affecting about 1.3%) than in Caucasians (affecting about 2.5%), it is not rare in either demographic, and it carries a substantial burden in both groups. We also observed that African Americans reported more extensive skin involvement compared with Caucasians. Follow-up, larger and more detailed studies have since demonstrated that African Americans and Asians experience worse impairment in quality of life from psoriasis even when controlling for objective measures of severity.

The reasons why patients with skin of color have worse impacts on quality of life from psoriasis are not well understood. As clinicians, we know that post-inflammatory hyperpigmentation and hypopigmentation are substantial problems for our patients with skin of color (Figure). We can clear psoriasis within weeks or months, but the dyspigmentation often lasts for years. Dr. Amy McMichael offers a number of clinical pearls, noting that phototherapy can be helpful for post-inflammatory hypopigmentation and a number of topical agents are reported to help with post-inflammatory hyperpigmentation. None of these modalities have been rigorously tested in clinical trials to prove that they result in clinically meaningful benefit in post-inflammatory dyspigmentation, so we are left with a major gap in clinical evidence and a large unmet clinical need.

The best approach we have to treating post-inflammatory hyperpigmentation is to prevent it in the first place by adequately treating psoriasis. Analyzing Medicare data, Dr. Junko Takeshita found that African Americans were 70% less likely to receive a biologic for psoriasis compared with Caucasians (I am a co-author on this paper). Dr. Takeshita’s follow-up work suggests some of the difference in use of biologics in African Americans with psoriasis may be multifactorial, stemming from clinicians having less confidence in diagnosing psoriasis in pigmented skin to patients of color being underrepresented in direct-to-consumer advertising.

I am a firm believer in the use of rigorous research to achieve better outcomes for our patients. Dr. Seemal Desai rightly emphasizes that we have a huge unmet need for including patients with skin of color in our studies. I am leading the LITE study, a pragmatic trial of 1,050 patients with psoriasis treated with home or office phototherapy. We specifically designed the study to ensure equal representation of patients with skin of color (for example, we will have 350 patients with Fitzpatrick skin type V or VI), so we can ensure the treatments are similarly effective regardless of skin type and reduce the gap in knowledge we have regarding how well psoriasis treatments work in patients with skin of color. The study is ongoing (www.thelitestudy.com), and we are especially interested in collaborating with colleagues who take care of psoriasis patients with skin of color. Come join us, so we can make progress together.

References:

Gelfand JM, et al. J Am Acad Dermatol. 2005;doi:10.1016/j.jaad.2004.07.045.

Kaufman BK, et al. Am J Clin Dermatol. 2018;doi:10.1007/s40257-017-0332-7.

Shah SK, et al. J Drugs Dermatol. 2011;10(8):866-872.

Smedley BD, et al. Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care. National Academy Press; 2003.

Takeshita J, et al. J Invest Dermatol. 2015;doi:10.1038/jid.2015.296.