In a recent article in Arthritis Care & Research, Stamm et al identified limitations in the existing activity measures for systemic lupus erythematosus (SLE) (1). Specifically, coverage gaps in the activity measurement of body structure and function and the failure to assess environmental and personal factors were noted as deficiencies. With respect to coverage gaps, the authors lamented the lack of a cutaneous outcome measure for SLE. We are pleased to inform the authors that such an outcome measure already exists. The Cutaneous Lupus Disease Activity and Severity Index (CLASI) is a validated cutaneous outcome measure for SLE that assesses both the activity and damage of cutaneous SLE lesions. First validated for use by dermatologists (2), the CLASI validation extension to rheumatology has been recently published in this journal (3). It was also recently presented in poster form at the 71st Annual Scientific Meeting of the American College of Rheumatology, Boston, MA, November 2007. Furthermore, the CLASI has been demonstrated to be responsive to changes in disease activity and damage during pharmacologic treatment intervention (4).
As far as quality of life (QOL) measurements are concerned, we found that the Skindex 29 is a helpful instrument to assess skin-related QOL in cutaneous lupus patients (5). When we used the instrument for assessment of cutaneous lupus patients, we added 3 additional questions related to sun exposure, outdoor activities, and hair loss. However, although the Skindex 29 does address a majority of the issues identified in the manuscript by Stamm et al, we found that the correlation between improvement of the skin condition and change in the Skindex score is not as straightforward as we expected (6). Whether this puzzling lack of correlation between skin health and skin-related QOL will hold true in a larger sample is currently being investigated.