METHODS: We used data from a large multicenter, longitudinal SLE cohort in which patients received standard of care. The first visit with active disease (defined as SLE Disease Activity Index 2000 [SLEDAI-2K] score ≥6) was designated as baseline, and mSRI attainment (defined as a reduction in SLEDAI-2K ≥4 points with no worsening in physician global assessment ≥0.3 points) was determined at annual intervals from baseline up to 5 years. Associations between mSRI attainment and outcomes including disease activity, glucocorticoid dose, flare, damage accrual, Lupus Low Disease Activity State (LLDAS), and remission were studied.
RESULTS: We included 2,060 patients, with a median baseline SLEDAI-2K score of 8. An mSRI response was attained by 56% of patients at 1 year, with similar responder rates seen at subsequent annual time points. Compared to nonresponders, mSRI responders had significantly lower disease activity and prednisolone dose and higher proportions of LLDAS and remission attainment at each year, and less damage accrual at years 2 and 3. Furthermore, mSRI responder status at 1 year predicted clinical benefit at subsequent years across most outcomes, including damage accrual (odds ratio [OR] range 0.58-0.69, P
METHODS: We included patients from a multicentre longitudinal cohort (recruited between May 1, 2013, and Dec 31, 2019) with active SLE (SLEDAI-2K ≥6) coinciding with an abnormality in at least one of 13 routine laboratory tests, at a visit designated as baseline. At 12 months, we analysed associations between thresholds of improvement in individual laboratory test results, measured as continuous variables, and five clinical outcomes using logistic regression. Primary outcomes were damage accrual and lupus low disease activity state (LLDAS), and secondary outcomes were modified SLE responder index (mSRI), physician global assessment (PGA) improvement of at least 0·3, and flare.
FINDINGS: We included 1525 patients (1415 [93%] women and 110 [7%] men, 1328 [87%] Asian ethnicity) in separate subsets for each laboratory test. The strongest associations with LLDAS and damage protection were seen with improvements in proteinuria (complete response: adjusted odds ratio [OR] 62·48, 95% CI 18·79-208·31 for LLDAS, OR 0·22, 95% CI 0·10-0·49 for damage accrual), albumin (complete response: adjusted OR 6·46, 95% CI 2·20-18·98 for LLDAS, OR 0·42, 95% CI 0·20-1·22 for damage accrual), haemoglobin (complete response: adjusted OR 1·97, 95% CI 1·09-3·53 for LLDAS, OR 0·33, 95% CI 0·15-0·71 for damage accrual), erythrocyte sedimentation rate (complete response: adjusted OR 1·71, 95% CI 1·10-2·67 for LLDAS, OR 0·53, 95% CI 0·30-0·94 for damage accrual), and platelets (complete response: adjusted OR 4·82, 95% CI 1·54-15·07 for LLDAS, OR 0·49, 95% CI 0·20-1·19 for damage accrual). Improvement in serological tests were mainly associated with PGA and mSRI. White cell and lymphocyte count improvements were least predictive.
INTERPRETATION: Improvements in several routine laboratory tests correspond with clinical outcomes in SLE over 12 months. Tests with the strongest associations were discrepant with laboratory tests included in current trial endpoints, and associations were observed across a range of improvement thresholds including incomplete resolution. These findings suggest the need to revise the use of laboratory test results in SLE trial endpoints.
FUNDING: Abbvie.