SAT0296 SERUM LEPTIN LEVELS IN SYSTEMIC SCLEROSIS PATIENTS WITH ELECTROCARDIOGRAPHIC ABNORMALITIES

Background: Electrocardiographic (ECG) abnormalities are described in 25-75% Systemic Sclerosis (SSc) cases and they are associated with other systemic manifestations as well as with a worse prognosis. There is an increasing need for clinical and laboratory biomarkers to ameliorate the diagnostic and therapeutic approaches to patients with ECG abnormalities, due to their actual low sensitivity and specificity. Adipokines are circulating proteins that appear dysregulated in SSc and leptin in particular is synthesized in response to inflammatory conditions and seems to play a proinflammatory and pro-fibrotic action in SSc. Interesting, many studies in the last years have underlined its role in the cardiac remodeling mechanisms and in the development of cardiac fibrosis in other chronic diseases. Objectives: Aim of our study is to evaluate the role of leptin in the development of cardiac rhythm disorders (CRD) during SSc. Furthermore, by the analysis of the clinical and demographical parameters of our SSc patients, we tried to define other possible features associated with increased serum leptin concentration. Methods: We included eighty-five SSc patients, fulfilling the 2013 ACR/EULAR classification criteria, attending the Regional Rare Disease Center of Policlinico Umberto I of Rome. Fifty presented significant CRD at non-invasive diagnostic techniques (12 Lead ECG, 24-hour Holter ECG). Demographic, clinical, conventional cardiovascular risk factors were examined; instrumental and laboratory assessments were obtained, together with ECG recordings. Thirty-five SSc patients without pathologic finding at ECG traces, matched for demographic and clinical features, were recruited as the control group. In all cases, after obtaining written informed consent, blood samples were taken to measure serum levels of leptin using an ELISA assay (Life Technologies-Italia). Results: The fifty SSc patients with CRD (mean age 51±15 years; F:M 41:9) had pulmonary fibrosis (PF) in 32 cases (64%) and a BMI >25Kg/m2 in 22 (44%) while in the control group of thirty-five SSc patients (mean age 49±16 years; F:M 33:2) PF was found in 15 (43%) and a BMI >25Kg/m2 in 9 (35%); We detected significantly higher median values of serum leptin in SSc patients with CRD compared to the control group (12027 pg/ml IQR 12314 versus 6392 pg/ml IQR 7103; p 0,0009). Additionally, SSc patients with a BMI> 25 kg/m2 (31 cases) as well as those with PF (47 cases) showed a significantly higher median serum leptin levels compared to those with BMI Conclusion: To our knowledge this is the first report on high serum levels of leptin in SSc patients with CRD that also confirms its increase in those cases with a BMI >25 kg/m2 and with PF, according to scientific literature data. The role of leptin in the pathogenesis of SSc remains unclear although it is already known its involvement in the development of cardiac fibrosis during other chronic diseases. On the basis of these results we speculate on leptin involvement in the pathogenesis of CRD during SSc, although further studies are needed with larger cohort of patients. References: [1]Vacca A et al. Rheumatology, 2014 [2]Tyndall AJ et al. Ann Rheum Dis, 2010 [3]Muresan L et al. Iran J Pub Health, 2017 [4]Sanna T et al. Indian Pacing Electrophysiol J, 2009 [5]Riccieri V et al. Clin Exp Rheumatol, 2011 [6]Żolkiewicz J et al. Arch Dermatol Res, 2019 [7]Huby AC et al. Circulation, 2015 [8]Shulze PC et al. Clin Chim Acta, 2005 [9]Van de Hoogen F et al. Arthritis Rheum, 2013 [10]Gui X et al. Biochem Biophys Res Commun, 2018 Disclosure of Interests: Greta Pellegrino: None declared, Katia Stefanantoni Consultant of: Italfarmaco Boehringer Ingelheim, Fausta Facioni: None declared, Carlotta Angelelli: None declared, Antonietta Gigante: None declared, Roberto Badagliacca: None declared, Carmine Dario Vizza: None declared, Sergio Morelli: None declared, Edoardo Rosato: None declared, Valeria Riccieri: None declared