METHODS: In this prospective cohort study, we enrolled patients with SLE from 13 international centres that are part of the Asia Pacific Lupus Collaboration. Eligible patients were older than 18 years and fulfilled one of two classification criteria for SLE (1997 American College of Rheumatology criteria or the 2012 Systemic Lupus International Collaborating Clinics criteria). Visits were according to clinical need, with a minimum frequency of one visit per 6 months. We assessed attainment of remission on the basis of the eight DORIS definitions of remission, which varied in terms of serological activity, glucocorticoid use, and use of immunosuppresive agents; attainment of LLDAS; and disease flares at each visit. Irreversible organ damage accrual was recorded annually. Our primary aim was to assess exposure of patients to each of the remission definitions or LLDAS, and the respective association of these states with accrual of irreversible organ damage as the primary outcome measure. Occurrence of disease flares was the key secondary outcome. We used time-dependent Cox proportional hazards models and generalised linear models to assess DORIS definitions of remission and LLDAS in terms of their association with damage accrual and disease flares.

FINDINGS: Between May 1, 2013, and Dec 31, 2016, 1707 patients with SLE were recruited and followed for a mean of 2·2 years (SD 0·9), totalling 12 689 visits. Remission, depending on DORIS definition, was achieved in 581 (4·6%) to 4546 (35·8%) of 12 689 visits. Spending 50% or more of observed time in any remission state was associated with a significant reduction in damage accrual, except for the two most stringent remission definitions, for which the frequency of attainment was lowest. Remission definitions disallowing serological activity were associated with the greatest reductions in disease flares. LLDAS was more attainable than any remission definition and was associated with a similar magnitude of protection from damage accrual and disease flares. Sustained remission and LLDAS were associated with a wider spread of effect sizes for reduction in risk of damage. By analysing patients who met the definition for LLDAS but not remission, we found that LLDAS was significantly associated with reduction in damage accrual, independent of all definitions of remission, except the least stringent.

INTERPRETATION: Attainment of remission was associated with significant reductions in damage accrual and disease flares. LLDAS was more achievable than remission based on the DORIS criteria, but was similarly protective. Remission definitions with less stringency might be insufficiently distinct from LLDAS to substantially affect outcome measures, and further studies are needed to distinguish the protective effects of the various remission definitions.

METHODS: In this prospective cohort study, patients aged 18 years or older with SLE were recruited from 13 centres in eight countries and followed prospectively. Patients with at least two visits over the study period no more than 6 months apart were included in the longitudinal analysis. Patients with no visits in the final year of the study were censored from their last visit. Attainment of the lupus low disease activity state (LLDAS) was assessed at each visit. The primary outcome measure was accrual of irreversible end-organ damage, defined as at least a 1-point increase in the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. We used time-dependent hazard regression models and generalised linear models to measure the association between LLDAS (attainment at any timepoint, cumulative time in LLDAS, and sustained LLDAS) with accrual of irreversible end-organ damage or flare (key secondary outcome). This study is registered with ClinicalTrials.gov, NCT03138941.

FINDINGS: Between May 1, 2013, and Dec 31, 2016, 1707 patients were recruited and followed for a mean of 2·2 years (SD 0·9), totalling 12 689 visits. Attainment of LLDAS at any timepoint was associated with reduction in damage accrual (hazard ratio 0·59, 0·45-0·76; p<0·0001) and subsequent flare (0·65, 95% CI 0·56-0·75; p<0·0001). Cumulative time in LLDAS was associated with improved outcomes: compared with patients with less than 50% of observed time in LLDAS, those with at least 50% of observed time in LLDAS had reduced risk of damage accrual (0·54, 0·42-0·70; p<0·0001) and flare (0·41, 0·35-0·48; p<0·0001). Similarly, increased durations of sustained LLDAS were associated with incremental reductions in the risk of damage accrual. The association of LLDAS with reduced damage accrual was observed regardless of pre-existing damage or disease activity at study entry.

INTERPRETATION: LLDAS attainment is associated with significant protection against flare and damage accrual in SLE. These findings validate LLDAS as an endpoint for clinical studies in SLE.

METHODS: This multinational cohort study was conducted at 25 sites across 13 Asia-Pacific countries. We included adult patients aged 18 years or older with stable SLE who were receiving routine clinical care, had two or more visits and had attained stable disease at one or more visits. We categorised stable disease into: LLDAS (Systemic Lupus Erythematosus Disease Activity Index 2000 [SLEDAI-2K] score ≤4, Physician Global Assessment [PGA] ≤1, and prednisolone ≤7·5 mg/day); Definitions of Remission in SLE (DORIS) remission (clinical SLEDAI-2K score 0, PGA <0·5, and prednisolone ≤5 mg/day); or complete remission on therapy (SLEDAI-2K score 0, PGA <0·5, and prednisolone ≤5 mg/day). Stable disease categories were mutually exclusive. Tapering was defined as any decrease in dose of corticosteroids or immunosuppressive therapy (mycophenolate mofetil, calcineurin inhibitors, azathioprine, leflunomide, or methotrexate). Using multivariable generalised estimating equations, we compared flares (SELENA-SLEDAI Flare Index) at the subsequent visit after drug tapering. We used generalised estimating equations and Cox proportional hazard models to compare tapering attempts that had begun in LLDAS, remission, and complete remission.

FINDINGS: Between May 1, 2013, and Dec 31, 2020, 4106 patients were recruited to the cohort, 3002 (73·1%) of whom were included in our analysis. 2769 (92·2%) participants were female, 233 (7·8%) were male, and 2636 (88·1%) of 2993 with ethnicity data available were Asian. The median age was 39·5 years (IQR 29·0-50·0). There were 14 808 patient visits for patients in LLDAS, or remission or complete remission, of which 13 140 (88·7%) entered the final multivariable model after excluding missing data. Among the 9863 visits at which patients continued the same therapy, 1121 (11·4%) flared at the next visit, of which 221 (19·7%) were severe flares. Of the 3277 visits at which a patient received a tapering of therapy, 557 (17·0%) flared at the next visit, of which 120 (21·5%) were severe flares. Tapering was associated with higher odds of flare compared with continuing the same therapy (odds ratio [OR] 1·24 [95% CI 1·10-1·39]; p=0·0005). Of 2095 continuous tapering attempts, 860 (41·1%) were initiated in LLDAS, 596 (28·4%) in remission, and 639 (30·5%) in complete remission. Tapering initiated in LLDAS (OR 1·37 [95% CI 1·03-1·81]; p=0·029) or remission (1·45 [1·08-1·94]; p=0·013) had higher odds of flare in 1 year compared with complete remission. Tapering in LLDAS (hazard ratio 1·24 [95% CI 1·04-1·48]; p=0·016) or remission (1·30 [1·08-1·56]; p=0·0054) had a significantly shorter time to first flare than tapering initiated in complete remission. Attaining sustained LLDAS, remission, or complete remission for at least 6 months just before the time of taper was associated with lower odds of flare at next visit, flares in 1 year, and longer time to flare.

INTERPRETATION: Tapering of corticosteroids or immunosuppressive therapy in patients with stable SLE was associated with excess flares. Our findings suggest that drug tapering should be carefully considered, weighing the risks and benefits, and is best exercised in complete (clinical and serological) remission and after maintaining stable disease for at least 6 months.