Predictors of low quality of life in patients with discoid lupus
Year: 2017
Type: article
Study design: Observational Study
Abstract: Dear Editor, Discoid lupus erythematosus (DLE) is unique from other cutaneous lupus erythematosus (CLE) subtypes because of dyspigmentation and scarring, which are associated with quality of life (QoL) impairment in other skin disorders.1,2 While previous QoL studies have included heterogeneous cohorts of patients with CLE, we focused on patients with DLE to identify clinical and demographic features that correlate with QoL impairment. We hypothesized that greater skin disease activity, skin disease damage, dark skin type, female sex, low socioeconomic status (defined by annual income) and current smoking status would be associated with poorer QoL in patients with DLE. A cross‐sectional pilot study was performed of 117 patients with DLE consecutively enrolled between April 2010 and April 2014 in outpatient dermatology clinics in the University of Texas Southwestern Medical Center and Parkland Health and Hospital System. Patients with a diagnosis of DLE based on clinical and/or histological evidence and over 18 years of age were included. This study was approved by the University of Texas Southwestern Institutional Review Board. We collected demographic information, medications, disease history and disease severity assessments (e.g. Cutaneous Lupus Activity and Severity Index – CLASI). Patients completed the QoL questionnaire SKINDEX‐29+3, which contained three additional lupus‐specific questions about concerns of sun exposure, hair loss and limitation of outdoor activities. These scores were primary outcomes, and high scores represented poor QoL.3 Patient characteristics were summarized as frequencies and percentages for categorical variables, and as medians and interquartile ranges for continuous variables. Relationships between SKINDEX‐29+3 domain scores and predictor variables were evaluated by univariable and multivariable regression analyses. In addition to independent variables with P‐values < 0·05 in the univariable analyses, we selected six variables (sex, smoking, annual income, CLASI activity, CLASI damage and skin type) based on prior literature4,5 and clinical experience to be included a priori in the multivariable analyses for each SKINDEX‐29+3 domain. Statistical analysis was performed with SAS 9.4 (SAS Institute Inc., Cary, NC, U.S.A.). The multivariable analyses (Table S1; see Supporting Information) revealed that female sex and current smoking status were significantly associated with poorer QoL in the SKINDEX‐29+3 emotions domain. In the SKINDEX‐29+3 functioning domain, we identified significant predictor variables including current smoking status and lower annual income. Higher CLASI activity scores, female sex and current smoking status significantly correlated with higher SKINDEX‐29+3 symptoms scores. Female sex was significantly associated with higher SKINDEX‐29+3 lupus‐specific scores. High SKINDEX‐29+3 scores in all four domains did not correlate with dark skin types or high CLASI damage scores. Figure 1 provides box and whisker plots of significant predictor variables and their SKINDEX‐29+3 scores. Female sex was associated with poorer QoL in DLE for the SKINDEX‐29+3 emotions, symptoms and lupus‐specific domains (Fig. 1a–d). Reporting annual income < $10 000 was associated with poorer QoL in the SKINDEX‐29+3 functioning and symptoms domains vs. income > $50 000, and in the SKINDEX‐29+3 lupus‐specific domain vs. those between $10 000 and $50 000 (Fig. 1e–h). Current smokers had higher SKINDEX‐29+3 scores than noncurrent smokers in the emotions, functioning and symptoms domains (Fig. 1i–l). SKINDEX‐29+3 scores in patients with discoid lupus erythematosus (DLE) subdivided by sex, income level and smoking status. SKINDEX‐29+3 scores in the emotions, functioning, symptoms and lupus‐specific domains were compared between patients with DLE who were male (n = 20) and female (n = 97) (a–d); had annual incomes < $10 000 (n = 41), $10 000–50 000 (n = 35) and > $50 000 (n = 26) (e–h); and were current smokers (n = 49) and not current smokers (n = 68) (i–l). The lower and upper limits of the box indicate the 25th and 75th percentiles (with values indicated), the line within the box depicts the median (with values indicated), and the whiskers (error bars) below and above the box indicate the minimum and maximum values. Social factors may play a role in the greater QoL impairment seen in female patients with DLE. Women are more negatively affected by their hair loss and dyspigmentation in other skin diseases that present with these features, such as cicatricial alopecias and vitiligo.6,7 The negative effect of smoking on QoL in patients with DLE may reflect poor responsiveness to therapy such as antimalarials, and a heightened inflammatory response. Patients with DLE with low socioeconomic status are at risk for poor QoL, likely due to limited access to medical care, difficulty with transportation, lack of insurance or inability to afford medications. The lack of significant correlation between CLASI damage scores and SKINDEX‐29 scores may be due to patients’ adjustment to their disease over time, as patients with DLE may be impacted by disease activity more than by the permanent sequelae of their disease.8 The nonsignificant association of dark skin type and high SKINDEX‐29 scores may reflect limitations in the SKINDEX‐29+3 questionnaire, which does not contain numerous questions specific to dyspigmentation. In focus‐group sessions with patients with DLE, in which several had dark skin types, many noted the negative impact of their dyspigmentation and scarring through negative social perceptions and daily lifestyle adjustments to mask them (M. E. Ogunsanya & B. F. Chong, unpublished observations). Thus, we are devising a disease‐specific questionnaire for CLE that probes more into these concerns and would help track disease improvement in future clinical trials. Our results highlight predictors of QoL impairment in patients with DLE, including female sex, being a current smoker and having lower socioeconomic status. Limitations include the study's cross‐sectional nature and location at two outpatient clinics, which restricted generalizability. Providers can ask those at risk for worse QoL additional questions probing emotions about their DLE, impact on daily life activities such as going outdoors and severity of skin symptoms such as itching. The authors would like to thank Rose Ann Cannon and Jack O'Brien for assisting in manuscript preparation and Dr Rebecca Vasquez, Dr Andrew Kim, Dr Daniel Grabell and Dr Tina Vinoya for help in recruitment of patients. Funding sources: the research reported in this publication was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under award number K23AR061441, and by the National Center for Advancing Translation Sciences of the National Institutes of Health under award number UL1TR001105. The content is solely the responsibility of the authors and does not necessarily represent the official views of The University of Texas Southwestern Medical Center at Dallas and its affiliated academic and healthcare centres, the National Center for Research Resources or the National Institutes of Health. Conflicts of interest: B.F.C. is an investigator for Daavlin Corporation and Biogen Incorporated. Table S1. SKINDEX‐29+3 scores in patients with discoid lupus erythematosus: multivariable analyses.
Source: British Journal of Dermatology
DOI: 10.1111/bjd.15490
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2602509671