To identify discrete clusters of systemic lupus erythematosus (SLE) patients based on symptoms and investigate differences across clusters.
Data were collected in the United States of America and five European countries via the Adelphi Real World Lupus Disease Specific Programme™, a cross-sectional survey. Rheumatologists provided data for five consecutively consulting adult patients with SLE, who were invited to participate. Identified SLE symptoms were reduced to factors based on commonly concurrent symptoms, using principal-component factor analysis. Factors were used as covariates in a latent class cluster analysis to identify discrete patient clusters. Patient-reported outcomes and physician-reported data were compared across clusters.
Among 1,376 patients, 87% of patients were female and 74% of patients were white. We identified four patient clusters ("very mild", "mild", "moderate", "severe") based on 39 signs/symptoms. Physician-reported symptom burden, organ involvement, disease activity and number of flares increased with increasing cluster severity (p<0.0001). Patient-reported impact (health status, fatigue, work productivity impairment, anxiety/depression, emotional impact) increased with increasing cluster severity (p<0.0001). Glucocorticoid and immunosuppressant use increased, and anti-malarial use decreased, with increasing cluster severity. In all clusters, <20% of patients received biologics; >15% of patients not receiving biologics were considered eligible for treatment by their physician. The proportion of physicians and patients satisfied with treatment decreased with increasing cluster severity (p<0.0001).
Our large, international real-world survey of SLE patients and physicians demonstrated strong associations between increased impairment, organ involvement and humanistic burden in SLE, highlighting unmet need for effective treatment options in high disease activity patients.