Validation of the Lupus Low Disease Activity State (LLDAS) in the Asia Pacific Region

Lupus Low Disease Activity State (LLDAS) study is an international, multi-centre prospective study, developed by the Asia Pacific Lupus Collaboration (APLC) to investigate whether the attainment of LLDAS is associated with improved outcomes in patients with Systemic Lupus Erythematosus (SLE). SLE, or lupus, is the archetypal multisystem autoimmune disease, with an estimated incidence of 5-50 cases per 100,000 people. Patients with SLE, usually young women, suffer a marked loss of life expectancy, and severe morbidity, due to a heterogeneous range of clinical manifestations caused by autoimmune-mediated inflammation of multiple organs. The most severe manifestations of SLE are the accrual of irreversible organ damage, especially renal and central nervous system (CNS) involvement. As there is no effective targeted monotherapy for SLE, patients also suffer severe toxicity from the use of glucocorticoids and broad-spectrum immunosuppressive therapies. Despite combination therapy with current drugs, many studies show that the majority of patients suffer inadequate disease control and inexorably accrue permanent organ damage over time. The diversity of clinical features of active SLE has made quantification of disease activity problematic. Although there are a number of published systems in use to measure SLE disease activity, there are widely acknowledged problems with these instruments. Published definitions of remission are so stringent that they are met by less than 5% of patients. This lead to the realisation that rather than lupus remission, a lupus low disease activity state target may be more feasible, and that patients with low disease activity are more homogeneous than patients with active disease. Thus, the development of a definition of lupus low disease activity, which is feasible and has face validity, escapes the complexity of attempts to quantify heterogeneous states of active disease. In this study, the investigators will prospectively collect longitudinal data on consecutive SLE patients at each centre to evaluate the LLDAS definition. Protection from organ damage accrual as the primary endpoint.

In this study, patients with SLE will be followed for \~ 5 years. Regular recordings of the data needed to score LLDAS (disease activity and treatment domains, see Franklyn L et al, Ann Rheum Dis 2016) will be collected, as well as annual recording of lupus-related damage using the SLICC\_ACR Damage Index (SDI) and quality of life using the Short Form 36 version 2 (SF36v2). At conclusion of primary data collection, the associate of LLDAS attainment, or sustained attainment, with protection from organ damage accrual will be ascertained.