Background/Purpose: The natural disease course of patients with cutaneous lupus erythematosus (CLE) on standard-of-care treatments is not fully characterized. We sought to characterize their disease course by obtaining Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) scores in these patients over time. We identified clinical and demographic features associated with different disease activity and damage trends.

Methods: This was a prospective cohort study of patients with CLE who had CLASI scores collected from ≥3 study visits within a 2-year time period. Patients were recruited from outpatient dermatology clinics at University of Texas Southwestern Medical Center and University of Pennsylvania from January 2007 to August 2016. Disease activity and damage trends were evaluated by net area under the curve (AUC) in CLASI scores/time and change in CLASI scores/time (slope). We defined “improving” and “worsening” trends by net AUC/time ≤-4 and ≥4, respectively. If net AUC/time was between -4 and 4, we used the best-fit slope to classify “improving” (m≤-1), “worsening” (m≥1) or “stable” (-1<m<1) trends. These metrics were compared between patient subgroups separated by demographics and clinical characteristics using Mann-Whitney and Kruskal-Wallis tests (continuous variables) and chi-squared tests (categorical variables). Linear regression models were used to compare CLASI score trends between groups.

Results: 83 patients with CLE were included, with mean follow-up time of 3.6 years. 81.8% patients with initial CLASI activity (CLASI-A) scores ≥10 (N=33) had improving disease activity, compared with 16.0% of those with initial CLASI-A ≤9 (N=50). Patients with baseline CLASI-A ≤9 had higher percentages of stable (56.0% vs. 9.1%) and worsening disease activity (28.0% vs. 9.1%) than those with initial CLASI-A≥10 (p<0.0001). Linear regression analyses showed significant improvement in CLASI-A scores over time in patients with baseline CLASI-A ≥10 (p<0.0001), baseline CLASI damage (CLASI-D) ≥10 (p=0.0001), African Americans (p=0.049), and CLE disease duration ≤1 year (p=0.01). 46.4% patients with baseline CLASI-D ≥10 (N=28) had improving disease damage trends, compared with 5.4% of those with initial CLASI-D ≤9 (N=55), respectively. Patients with baseline CLASI-D ≤9 had higher percentages of stable (67.3% vs. 35.7%) and worsening disease activity (27.3% vs. 17.9%) than those with initial CLASI-A ≥10 (p=0.0003). Patients with baseline CLASI-A or CLASI-D ≥10 showed negative net AUC/time and slopes (Table).

Conclusion: Most patients with high and low baseline CLASI-A and -D showed improving and stable trends, respectively. This natural disease course data may be used as historical controls for future clinical trials.

Table. Net AUC/time and slope in sub-groups of patients with baseline CLASI scores ≥10 or ≤9

ACR Meeting Abstracts - https://acrabstracts.org/abstract/natural-history-of-disease-activity-and-damage-in-patients-with-cutaneous-lupus-erythematosus-on-standard-of-care-treatments-using-longitudinal-registries-from-two-academic-dermatology-centers/