122 High burden of immunosuppressant use in undifferentiated connective tissue disease: results from the Lupus Extended Autoimmune Phenotype Study (LEAP) cohort

Abstract

Background: Connective tissue diseases (CTDs) are heterogeneous with overlapping clinical features and shared immunopathology. This study sought to assess the clinical characteristics, arterial stiffness and therapeutic exposures of UCTD patients compared to other CTD cohorts and healthy controls, using both clinician diagnosis and classification criteria. Method(s): Data was collected prospectively in 181 CTD patients in Lupus Extended Autoimmune Phenotype Study (LEAP) between May 2014 and June 2017. Nineteen healthy controls (HCs) were also recruited. Patients were initially grouped according to clinician diagnosis. Patients with a clinician diagnosis of UCTD were reviewed and reclassified, where appropriate, using ACR-1982/1997 SLE, ACR/ EULAR-2016 Sjogren's syndrome, ACR/EULAR-2013 systemic sclerosis, and 1975-Myositis criteria. Arterial stiffness (pulse wave velocity -PWV) was measured using the TensioMed device (TensoMed LTD, Budapest). The association between PWV and disease subtype was investigated using linear regression models. Result(s): The baseline characteristics are described in Table 1. UCTD patients had comparatively shorter disease duration than many CTDs but significant treatment burden with 15 (33%) taking an immunosuppressant and 20 (44%) taking oral steroids. The UCTD patients had no renal disease and reduced frequency of serositis, pulmonary artery hypertension and interstitial lung disease. Although lower in HCs, There was no significant difference in PWV between HCs and any disease group, when adjusted for age and gender. PWV was similar in both SLE and uCTD groups. Using the classification criteria, 15 UCTD patients could be reclassified as having SLE and 1 with Sjogren's syndrome; relating predominately to musculoskeletal and cutaneous features including ulcers (31%), photosensitive rash (41%) and arthritis (55%) rather than deep-organ manifestations. There was higher immunosuppressant-use in reclassified UCTD patients (62% vs 39% p=0.013) suggesting they required more aggressive intervention. Of the patients reclassified, 50% were ENA positive, 6% were antidsDNA positive, and 47% were anti-cardiolipin or lupus anticoagulant positive. Conclusion(s): The clinical features of UCTD are predominately musculoskeletal and cutaneous. Despite this, patients are often exposed to (Table Presented) significant burden of therapies, including immunosuppressants and steroids. Patients with UCTD may meet classification criteria for other CTDs, notably SLE, and it is important to continuously reassess these patients for new or evolving features.