Objective: Having developed and validated a disease-specific health-related quality of life (HRQOL) measure for patients with systemic lupus erythematosus (SLE), the LupusQoL, we determined its relationship to demographic and clinical measurements in a group of patients with SLE.
Methods: A group of 322 outpatients completed the LupusQoL. Demographic (age, sex, marital status, ethnicity) and clinical variables (disease duration, disease activity, damage) were recorded. Associations between the 8 LupusQoL domains and age, disease duration, disease activity, and damage were explored using Spearman's correlation coefficients. Differences in LupusQoL scores were examined for sex and marital status using the Mann-Whitney U test. Ethnic groups were compared using ANOVA.
Results: All domains of LupusQoL were impaired, with fatigue (56.3) being the worst affected and body image (80.0) the least. The correlations between the LupusQoL domain scores and age (r = -0.01 to -0.22) and disease duration (r = 0 to 0.16) were absent or weak. Similarly, there were no significant differences in the LupusQoL scores regarding sex, marital status, or the 3 main ethnic groups (Black-Caribbean, Asian, White). Although there were statistically significant correlations between the scores of the LupusQoL domains and some scores of the British Isles Lupus Assessment Group index (r = -0.22 to 0.09) and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (r = -0.29 to 0.21), these were weak.
Conclusion: HRQOL was impaired in this cohort of outpatients with SLE as assessed by the validated lupus-specific LupusQoL. There were no clinically important associations between the 8 domains of the LupusQoL and clinical or demographic variables in this group of patients. Thus, the LupusQoL is a relatively independent outcome measure in patients with SLE.