Objective: To evaluate the relationship between renal activity and quality of life (QOL) in patients with systemic lupus erythematosus (SLE).
Methods: Three hundred eighty-six patients completed annual Medical Outcomes Study Short Form-36 questionnaires and physicians completed the SLE Disease Activity Index and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. Concurrent association between renal activity and QOL was evaluated through regression models that adjusted for demographics and nonrenal disease activity and nonrenal damage. To characterize the longitudinal relationship between change in renal activity and change in QOL, all renal activity and QOL data over the entire study were used to estimate a linear trend within each individual patient through hierarchical modeling.
Results: In the regression model that assessed the association between renal activity and QOL, on average, each additional renal activity item fulfilled was associated with a 2.04-unit (95% CI 0.88, 3.24) decrease in the physical function subscale, a 5.28-unit (95% CI 2.76, 7.76) decrease in the role-physical subscale, a 2.24-unit (95% CI 0.72, 3.80) decrease in the social function subscale, and a 1.16-unit (95% CI 0.60, 1.72) decrease in the physical component summary score. In the hierarchical model, no association was observed between changes in renal activity and QOL.
Conclusion: Patients with SLE and active renal disease concurrently experience a slightly poorer QOL than those without renal disease, especially in the physical domains. Because the confidence intervals were wide, we could not accurately estimate whether a longitudinal change in renal activity was associated with a change in QOL.