Discoid lupus erythematosus skin lesion distribution and characteristics in Black patients: a retrospective cohort study

OBJECTIVE: Epidemiological studies have shown that discoid lupus erythematosus (DLE) has a higher incidence and prevalence in racial/ethnic minority groups, particularly Black individuals. The objective of this retrospective cohort study was to identify the differences in DLE lesion distribution and characteristics in Black individuals compared with non-Black individuals. METHODS: 183 patients with DLE (112 Black patients and 71 non-Black patients) with a reported race/ethnicity and Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) scores were included in this retrospective cohort study. Univariate analysis was performed to determine significant differences in demographic data, clinical characteristics, DLE lesion distribution and DLE lesion characteristics in Black and non-Black patients with DLE. Multivariable logistic regression was preformed to determine significant predictors of DLE lesion location and characteristics. RESULTS: Black patients with DLE had worse baseline CLASI damage scores compared with non-Black patients with DLE (median (IQR): 10.0 (6.0–14.5) vs 6.0 (3.0–10.0), p<0.001) and had 48.9 greater odds of dyspigmentation in any anatomical location (p<0.001). Black patients had 2.54 greater odds of having scalp involvement (p=0.015) and 1.97 greater odds of having ear involvement (p=0.032) compared with non-Black patients. Black patients also had greater odds of scalp dyspigmentation (OR=5.85, p<0.001), ear dyspigmentation (OR=2.89, p=0.001) and scarring alopecia (OR=3.00, p=0.001) compared with non-Black patients. CONCLUSIONS: Signs of disease damage, particularly ear dyspigmentation, scalp dyspigmentation and scarring alopecia, can more frequently affect Black patients with DLE. Recognising differences in clinical presentation of DLE among Black patients can assist future efforts with understanding biological, cultural, psychosocial and systemic factors that influence DLE presentation and outcomes in Black patients and may guide clinicians when counselling Black patients.