By Dr Wendy Stevens & Dr Laura Ross

The accurate measurement of scleroderma, including the overall impact of the disease and important changes in response to treatment, has proven to be challenging for researchers. To address this, the research team at St Vincent’s Hospital Melbourne has been working for a number of years to develop a new measurement tool – the Scleroderma Clinical Trials Consortium Activity Index. The lead researcher has been Dr Laura Ross from St Vincent’s Hospital Melbourne. This research was part of Laura’s PhD work. Laura was awarded the Melbourne University Faculty of Medicine Dean’s Prize for Graduate Research Excellence and the TJ Martin Medal for best PhD on the St Vincent’s Campus in 2023 for her work on the development of the index.

This project has resulted in a multi-system activity index that we hope can quantify how active an individual’s scleroderma is at any given point. We envisage that this index may be used in clinical trials and epidemiologic studies. It may be used to measure response to treatment in clinical trials or to predict important patient outcomes.

The process of developing any activity index in any disease is long and complex and requires extensive collaboration with researchers in the field around the world, as well as input from people living with the condition. To develop the index, we collaborated with more than 30 scleroderma researchers and patient research partners from around the world. The first task was to define what ‘activity’ in scleroderma is. The next step was to develop methods of assessing disease activity across nine different internal organ systems (e.g. gastrointestinal system, lungs, heart, vascular etc.). The challenge with scleroderma is that so many different organ systems can be involved and everybody with scleroderma has different disease manifestations.

In some organs there are already clearly developed measures that could be used to measure activity, such as lung function tests for the lungs and the Modified Rodnan skin score for the skin. However, in other organs systems such as the gut no such measures exist.

So, in order to complete the development of our activity index, we spent time examining the role of patient-reported symptoms in assessing changes in scleroderma. We considered novel methods of assessing gut manifestations of scleroderma using patient reported symptoms and validated these across three ASIG sites. Another important decision was how frequently we should be performing assessments of disease activity in the setting of clinical trials. 

Complex statistical modelling was used to weigh the final items, using data from the Australian Scleroderma Cohort Study. The index was also validated using data from the Canadian Scleroderma Research Group database.

The final index contains 24 items. The results of this project have recently been presented at the EULAR Congress (Milan 2023), one of the largest international rheumatology scientific meetings held each year. The presentation was awarded an Abstract Prize by the conference organising committee in recognition of its contribution to the field of scleroderma research. The next step will be to use the new Activity Index in a variety of settings, including randomised controlled trials and new interventions to further test our new measurement tool.

References

Ross L, Baron M, Nikpour M The challenges and controversies of measuring disease activity in systemic sclerosis, J Scleroderma Relat Disord 2018 3(2) 115-121

Ross L, Stevens W, Wilson M, Strickland G, Walker J, Sahhar J, Ngian GS, Roddy J, Major G, Proudman S, Baron M, Nikpour M Can Patient-Reported Symptoms Be Used to Measure Disease Activity in Systemic Sclerosis? Arthritis Care Res 2020 72(10) 1459-1465

Ross L, Proudman S, Walker J, Stevens W, Ferdowsi N, Quinlivan A, Morrisroe K, Baron M, Nikpour M Evaluation of Patient and Physician Assessments of Gastrointestinal Disease Activity in Systemic Sclerosis, J Rheumatol 2023 50(4) 519-525