AB0545 DYNAMICS OF N-TERMINAL FRAGMENT OF BRAIN NATRIURETIC PEPTIDE PROGENITOR LEVEL IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS, WITHOUT HEART FAILURE SIGNS BEFORE AND AFTER IMMUNOSUPPRESSIVE THERAPY
Authors: Tatiana Panafidina, Tatiana Popkova, Maria Cherkasova
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Cardiovascular mortality is increased in systemic lupus erythematosus (SLE). Elevated plasma concentration of N-terminal fragment of brain natriuretic peptide progenitor (NT-proBNP) is a laboratory marker of heart failure (HF), associated with cardiovascular morbidity and mortality in the general population. <h3>Objectives:</h3> To measure NT-proBNP serum levels in SLE patients without HF signs before initiation of the therapy. To monitor NT-proBNP levels during therapy up to achieving SLE remission. <h3>Methods:</h3> The study included 15 patients (87% females, aged 31[29-33]years (median [interquartile range 25-75%]) with untreated SLE (ACR 1997 and SLICC 2012 criteria) without HF. These were patients with a new-onset and long-standing disease, who discontinued administered therapy. The control included 39 healthy donors (27[24-44]years, 87% females). A comprehensive SLE patients' evaluation was made twice: at baseline and at the end of follow up (FUP), median FUP was 7[2-7]years. Serum levels of NT-proBNP (pg/ml) were measured using electrochemiluminescence method Elecsys proBNP II (Roche Diagnostics, Switzerland). Normal NT-proBNP levels should vary within ≤125pg/ml. <h3>Results:</h3> At enrollment medial SLE duration was 1[1-7]years, SLEDAI-2K - 10[8-20], SLICC/DI - 0[0-1]scores, SLE patients had elevated (vs controls) values of NT-proBNP: 150,7[77,6-550,2] vs 44,6[29,7-66,91]pg/ml, <i>p&lt;</i><i>0,001,</i> NT-proBNP concentrations &gt;125pg/ml were found in 8(53%) SLE patients without HF. Glucocorticoids and hydroxychloroquine were initiated in all patients, and additionally cyclophosphamide was administered in 7(47%) patients, mycophenolate mofetil – in 10(67%), azathioprine – in 5(33%), rituximab – in 3(20%). By the end of FUP patients' median age was 36[34-39]years <i>p&lt;</i><i>0,001</i>, SLE duration - 8[7,5-11]years, stable remission was achieved in 14(93%) patients, a relapse of exacerbation was documented in 1(7%) patient, SLEDAI-2K - 2[0-4] <i>p</i><i>&lt;</i><i>0,01</i>, SLICC/DI - 1[0-2]scores <i>p&lt;</i><i>0,05</i>, NT-proBNP levels were comparable to values in the control group: 26,6[19,3-64,9] vs 44,6[29,7-66,91]pg/ml, <i>p&gt;</i><i>0,05</i>, with only one case (7%) with NT-proBNP level &gt;125pg/ml. Median NT-proBNP concentration dropped from 150,7[77,6-550,2] to 26,6[19,3-64,9]pg/ml, <i>р&lt;</i><i>0,001</i> when remission was achieved, therefore baseline rate of 53% of participants with elevated NT-proBNP concentration decreased to 7%, <i>р&lt;</i><i>0,01</i>. Patients achieving SLE remission on treatment also succeeded to normalize their NT-proBNP levels, and didn't show any signs of cardiovascular (CV) pathology or HF. In "naïve" to treatment SLE patients NT-proBNP levels showed positive correlation with concentrations of creatinine (r=0,614, p&lt;0,05), urea (r=0,614, p&lt;0,05), and also with interventricular septum myocardial thickness (r=0,557, p&lt;0,05), and showed negative correlation with glomerular filtration rate (GFR) (r=-0,579, p&lt;0,05). There was no association between NT-proBNP levels and clinical &amp; immunological SLE features, as well as markers of inflammation (CRP, IL-6, TNF-α), and TRF. <h3>Conclusion:</h3> NT-proBNP concentrations in "untreated" SLE patients with high disease activity and without CV pathology and HF were significantly higher than in the control group <i>(p&lt;</i><i>0,001),</i> and more than 50% of these patients had elevated NT-proBNP (&gt;125pg/ml) baseline concentration. Elevated NT-proBNP concentrations were associated with markers renal function (creatinine, urea, GFR). Adequate immunosuppressive therapy resulted in achievement of SLE remission and normalization of NT-proBNP concentrations. <h3>Disclosure of Interests:</h3> None declared