Prolonged clinical remission and low disease activity statuses are associated with better quality of life in systemic lupus erythematosus

Abstract

Objective The objective of this study was to determine the association between disease activity status and health-related quality of life (HRQoL) in systemic lupus erythematosus (SLE) patients. Methods SLE patients in an out-patient clinic during the previous 12 months were included in the study. The Systemic Lupus Erythematosus-specific Quality-of-Life questionnaire (SLEQoL) was administered at the last visit. Disease activity status was determined retrospectively during the previous year. The categories of disease activity status were defined as: clinical remission (CR): clinical quiescent disease according to Systemic Lupus Erythematosus Disease Activity Index 2000, prednisolone ≤ 5 mg/day; low disease activity (LDA): SLEDAI-2K (without serological domain) ≤ 2, prednisolone ≤ 7.5 mg/day; and non-optimally controlled status: for those who were not in CR/LDA. Immunosuppressive drugs (maintenance dose) and antimalarials were allowed. Prolonged CR or LDA was defined as those with sustained CR or LDA for at least one year. The association between disease activity status and HRQoL was assessed by using regression analysis adjusting for other covariates. Results Of 237 SLE patients, 100 patients (42.2%) achieved prolonged CR, 46 patients (19.4%) achieved prolonged LDA and 91 patients (38.4%) were not in CR/LDA. Non-CR/LDA patients had significantly higher total SLEQoL score and in all domains compared to CR/LDA patients. No significant difference in SLEQoL domain scores was found between CR and LDA groups. Multivariable analysis revealed that non-CR/LDA was positively associated with SLEQoL score compared with CR/LDA (β 20.02, 95% confidence interval (CI) 6.81–33.23, p < 0.003). Moreover, non-CR/LDA was at a higher risk of impaired QoL (SLEQoL score > 80) compared with CR (hazard ratio 3.8; 95% CI 1.82–7.95; p < 0.001). However, there was no significant difference between CR and LDA in terms of SLEQoL score or impaired QoL. Other factors associated with higher SLEQoL score were damage index (β 9.51, 95% CI 3.52–15.49, p = 0.002) and anemia (β 24.99, 95% CI 5.71–44.27, p = 0.01). Conclusion Prolonged CR and LDA are associated with better HRQoL in SLE patients and have a comparable effect. Prolonged CR or optional LDA may be used as the treatment goal of a treat to target approach in SLE.