POS0847 PREDICTORS OF PERSISTENT DISEASE IN SYSTEMIC SCLEROSIS: A SINGLE CENTRE PROSPECTIVE OBSERVATIONAL STUDY SPANNING A DECADE
Authors: V. Shobha, A. C Das, Y. As, S. Selvam, R. Aithala
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Systemic sclerosis (SSc) is a heterogeneous autoimmune disease with a prolonged clinical course, causing significant morbidity [1]. While clinical trials in recent years have enriched cohorts with early systemic sclerosis, little is known about the factors driving the disease in certain patients, even after a decade of the first non-Raynaud's symptom. <h3>Objectives:</h3> 1)<b></b>To describe the characteristics of a Late systemic sclerosis cohort from a single center. 2)<b></b>To define disease and treatment-related risk factors for activity on long-term follow-up. 3)<b></b>To explore the time to FVC worsening (&gt;10%) in the late systemic sclerosis cohort ILD subgroup. <h3>Methods:</h3> From the Institutional Systemic Sclerosis registry, we identified SSc patients diagnosed by Leroy &amp; Medsger criteria between January 1997 and December 2013. The total duration of illness was calculated from onset of first non-Raynaud's symptom. Those with ongoing follow-up confirmed by in-person visits or video consultations in the last 12 months (Jan-Dec 2023) were eligible for inclusion. Data on disease parameters, immunosuppression (IS) usage, defaults (IS &amp; non-IS)and hospitalization details were collected from medical records after ethics board approval. The participants were divided into inactive and active subgroups based on the definition used by investigators for revised EUSTAR Activity Index derivation cohort(ref). Inactive disease was defined as not requiring a change of treatment and follow-up after six months to 1 year; active disease was defined as requiring treatment intensification with 1-3 monthly follow-ups or hospitalization. Among the 51 screened patients, 7 were excluded (4- no follow-up, 1 -expired, 2-overlap). Consenting patients underwent Nailfold capillaroscopy (optipix v.1.7.6) to assess the current pattern. Data was analyzed by SPSSv.26 <h3>Results:</h3> Forty-four patients were classified as inactive(n=23) and active(n=21). The disease characteristics are summarized in Table 1. The clinical features of salt and pepper pigmentation, telangiectasias, complicated RP, ILD and GI involvement were significantly high in the active subset. An early scleroderma pattern was seen in 59%(n=13) out of 22 patients who underwent NFC. A late pattern showed a significant association with active disease(p=0.013). We sought to find if delay in initiating immunosuppression (IS) affects the disease course in the long term. We found a significant correlation between the time to start IS from RP and non-RP symptoms and active status after a decade. Other significant treatment factors were starting DMARDs alone or combined. The factors that showed significant correlation with activity were chosen for univariate logistic regression for odds ratio (OR), as described in Table 2. There was no significant correlation between total duration of immunosuppression intake, number, type (IS vs non-IS) or duration of drug defaults and active status in the long term. A significant correlation was found between the NFC pattern and TTIS-RP(p=0.026) and non-RP (p=0.024). The ILD subgroup had a mean age of 32.7±8.1 years, with disease duration of 14±3.8 years. The time to development of ILD was 36 (12-48) months from the first non-RP symptom. Among 27 patients with ILD, 17(62.96%) had at least 2 serial FVC measurements. The median time to &gt;10%FVC decline was less in the active group, Figure 1. There was no significant difference in time to decline among disease subsets, NFC patterns, or IS. The time to flare (any domain) after IS or non-IS default showed no significant difference between the active/inactive group, NFC pattern or ERA intake. The Time to improvement(months) post-flare was significantly prolonged in those who received prednisolone (5.2 months, 3.8-6.4 95%CI, <i>p=0.03</i>). <h3>Conclusion:</h3> In a prospective SSc cohort of 15-year duration, we identified salt &amp; pepper pigmentation, late pattern in NFC and delay in immunosuppression initiation as potential drivers of active disease in the long term. <h3>REFERENCES:</h3> [1] The EUSTAR task force for the development of activity criteria for systemic sclerosis: validation of revised EUSTAR activity index. Ann Rheum Dis 2017. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>