Evaluating Organ Systems in Lupus
Evaluating Organ Systems in Lupus
Capturing disease activity in lupus can be challenging. As a multisystem autoimmune disease, it is a complex and unpredictable disease that can make diagnosis challenging.
Researchers led by Anca Askanase, M.D., of Columbia University Medical Center, conducted a preliminary test of LFA-REAL (Lupus Foundation of America-Rapid Evaluation of Activity in Lupus) as a possible measure for systemic lupus erythematosus (SLE) disease activity. Their findings appear in Lupus Science & Medicine.
They found strong correlations between the test and existing lupus disease activity measures such as the SLE Disease Activity Index (SLEDAI), the British Isles Lupus Assessment Group Index (BILAG 2004) and the Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA) SLEDAI Physician’s Global Assessment (SS-PGA).
Dr. Askanase told Rheumatology Network that making quick and accurate disease evaluation easier for everyone involved in lupus care will have far-reaching positive implications.
“The more we understand how to improve disease measurements, the more likely we are to obtain improved outcomes and move toward treating targets in lupus,” she said. “We can target remission as opposed to ‘as good as it gets.’ We’ll achieve better outcomes in lupus, including longer life expectancy and having a better quality of life.”
Existing SLE disease measures
Existing tests vary in detail and data. SLEDAI, for example, includes 24 common manifestations measured in a point system to measure disease severity. The BILAG 2004 Index measures nine organ systems with 97 descriptors that are scored as "not present, improving, same, worse, new or recurrence" in the past month. The scores are calculated into a complex algorithm that matches the descriptions to the organ. SS-PGA is a 100 mm scale to assess a patient's overall disease activity from 0-3 range with 1 for mild disease actvity and two for moderate disease activity.
None of the measures are perfect. SLEDAI, for example, was not designed to detect worsening condition. In this case, if the minimal definition is met, it receives the same numerical weight regardless of its severity.
Neither the SELENA SLEDAI Flare Index or the SRI-50 (improvement index) addresses the fact that patients with severe disease cannot often be differentiated from patients with mild disease. However, BILAG does differentiate mild, moderate and severe activity, but doesn’t always score them clearly. It’s a complicated measure to learn, the researchers wrote.
SS-PGA is simple and intuitive, “but its compression of a broad spectrum of moderate to severe disease severity into a small region of the scale can be problematic in accurately evaluating disease progress, particularly when multiple organs are involved.”
“These outcome measures are still frequently misunderstood and scored incorrectly, even by experienced clinical trialists,” researchers stated in the article.
LFA-REAL has been designed to be “efficient but a scalable SLE disease activity measure” for use as both a reliable outcome measure in both clinical practice and trials.
“We believe that this system can be learnt by a clinician skilled in the care of lupus patients within minutes, and in practice it can be scored rapidly for most patients. Since it is constructed as an expanded version of PGA (based on completing a separate SS-PGA for each active organ system), it is designed to be sensitive to change and allow for precise and accurate measurement of disease severity and treatment progress,” the researchers wrote. “A tool that can be used in both clinical trials and practice would allow practicing clinicians to more easily interpret, evaluate and apply the findings from clinical trials.”