Article Text
Abstract
Background Cutaneous lupus erythematosus (CLE) is a potentially disfiguring, chronic autoimmune disease with variable skin manifestations, negatively affecting the quality of life (QoL) of patients. Patient-reported outcome (PRO) measures used in assessing QoL in CLE patients have been either generic or developed without input from patients with CLE. The objective of this study was to demonstrate the reliability and validity of a disease-specific QoL measure for CLE the cutaneous lupus erythematosus quality of life (CLEQoL).
Methods A total of 101 patients with a diagnosis of CLE were recruited at outpatient dermatology clinics at the University of Texas Southwestern Medical Center and Parkland Health and Hospital System in Dallas, TX. Each patient was asked to complete the CLEQoL and Short Form 36 (SF-36). The CLEQoL contains 29 questions from the SKINDEX, a generic skin disease QoL measure, three questions relating to photosensitivity and alopecia (adapted from the SKINDEX-29 +3), and four questions from the vitiligo-specific quality of life (VitiQoL) (figure 1). These questions were validated via focus groups of patients with CLE. Internal consistency was used as a measure of reliability. Validity was measured in two ways structural validity via exploratory factor analysis and convergent validity via Spearman correlations between CLEQoL and SF-36. Patient demographic and disease characteristics were collected. Data was analyzed using SPSS and significance was set to p<0.05.
Results The average age of our CLE patients was 48±13 with discoid lupus (n=72, 71.3%) being the most predominant CLE subtype. Patients were mostly female (n=88, 87.1%) and African-American/Black (n=59, 58.4%). Internal consistency ranged from 0.67 to 0.95. A total of five domains, functioning, emotions, symptoms, body image/cosmetic effects and photosensitivity, were extracted with a total explained variance of 71.06%. CLEQoL-related domains correlated with SF-36 domains (r ranging from −0.39 to −0.65). The Cutaneous Lupus Activity and Severity Index (CLASI) activity scores correlated positively with the CLEQoL functioning (r=0.24, p<0.05), emotions (r=0.26, p<0.05), and symptoms (r=0.32, p<0.05) domains. CLASI damage scores correlated positively with the CLEQoL body image/cosmetic effects (r=0.41, p<0.001) and photosensitivity (r=0.25, p<0.05).
Conclusions The CLEQoL was found to be a valid and reliable PRO measure for assessing QoL in patients with CLE. Demonstrating that the CLEQoL has strong psychometric properties is an important step towards the development of a disease-specific PRO measure for future CLE clinical trials.
Funding Source(s): This study was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases under Award Number K23AR061441.