We agreed that activity should be assessed in terms of constitutional features, mucocutaneous, central nervous system, musculoskeletal, cardiovascular respiratory, vasculitis, renal, and hematological organs or systems. In some instances, we asked outside experts for help. Original renal criteria were drawn up with the help of J. Stewart Cameron, MD, now emeritus professor of nephrology at Guy’s Hospital of King’s College in London.4 In abiding by the intention to treat principle, we had to agree which particular signs and symptoms in each organ or system, if present, would lead us to treat patients with a significant dose of corticosteroids (more than 25 mg prednisolone per day) with or without additional immunosuppressive drugs. This would then constitute the most “Active” form of disease (in that organ or system) and would be given grade A.
The B grade in each organ or system – in effect, a “Be aware” grade – envisaged a patient with active disease, also carefully defined, who required continuing steroid or immunosuppressive therapy but at a lower level; a C grade in each organ or system would imply “Contentment” meaning low-grade disease activity only, which might require just symptomatic therapy. The D grade implied inactivity in the respective organ or system. This was later divided into two grades: D for “Discount,” meaning the disease had once been active in this organ or system but was no longer active, and the E grade implying that the disease had never “Ever” been active in that organ or system.
Test of the System
The system we established provided a testable hypothesis. With a grant from the Arthritis Research Campaign, Dr. Hay visited five different rheumatology units around the United Kingdom to review patient notes to determine whether patients with grade A symptoms or signs were actually treated with the large steroid doses or immunosuppression. We also determined whether Dr. Hay’s assessment of the patients agreed with that of the local physician.
We were greatly encouraged by the results of Dr. Hay’s study, which showed strong correlations in seven out of eight of the systems.5 Only for the central nervous system was it difficult to obtain satisfactory agreement. By 1986, BILAG felt able to “go public” by presenting a poster at the 1st International Lupus Meeting in Calgary, Alberta. The organizers of this meeting placed this poster (which was defended by myself and Dr. Maddison) next to a poster describing the origins of the SLEDAI (defended by Drs. Urowitz and Gladman). The four of us felt that the issue of disease activity assessment was something that ought to be agreed globally. With the help of a grant from NATO three meetings were held between 1988 and 1991 to explore these indices and Dr. Liang’s SLAM index. Both real and paper patient exercises were undertaken with the support of other interested parties including Gunnar Sturfelt, MD, PhD, and Ola Nived, MD, PhD, both at Lund University in Sweden, and Keneth Kalunian, MD, at the University of California, San Diego.
