AB0229 Does expression level of vip and its receptors correlated with disease severity in early arthritis?
Authors: A Seoane, A Lamana, M Carriόn, Y Juarranz, R García-Vicuña, I González-Άlvaro, C Martínez, RP Gomariz
Journal: Annals of the Rheumatic Diseases (2017)

<h3>Background</h3> Rheumatoid Arthritis (RA) is a heterogeneous disease, not only in the course but also in the response to treatment (1). So, a major challenge is the classification of patients according to the disease severity/mildness to apply customized therapeutic strategies. Low vasoactive intestinal peptide (VIP) serum levels are associated to a worse clinical course in Early Arthritis (EA) (2) and the expression of its receptor VPAC1 is associated with disease activity (3). <h3>Objectives</h3> To identify in an Early Arthritis cohort associations between clinical parameters of severity and serum VIP levels or expression of their receptors VPAC1 and VPAC2. <h3>Methods</h3> We studied 212 patients from the PEARL (Princesa Early Arthritis Registry Longitudinal) study. Follow-up includes five visits (0, 6, 12, 24 and 60 months) in which we collect demographic, clinical, laboratory, therapeutic and radiological data, as well as biological samples. Since there is not a global disease severity variable for RA, we stratified severity as follows: A) remission after two years of follow-up defined as SDAI &lt;3.3 (4). B) Global Disease Assessment by Physician &gt;75th percentile of the population (severe disease) or &gt;25th percentile (mild disease). C) Median value in our population of the Δ erosion score (SvdH method assessed in hands) after two years of follow-up. VIP levels were determined by enzyme immunoassay and mRNA expression levels of VIP receptors in PBMCs by real-time PCR. To analyze the association between severity/mildness and the expression of VIP/VPAC we use several parametric and non-parametric hypothesis testing (t-test, ANOVA and Kruskal-Wallis) using Stata 12 for Windows (StataCorp PL, College Station, TX, USA). <h3>Results</h3> We observed a trend towards higher baseline VIP serum levels in patients who reached remission in terms of SDAI (p=0.1169). Patients no achieving remission showed lower VPAC1 expression (p=0.0494). Severe patients defined by GDAPh displayed a clear trend to lower VIP levels (p=0.081). Those patients also exhibited significant lower VPAC1 expression levels (p=0.0276). Concerning bone erosion score, we did not observe a significant association with VIP levels; interestingly we found that those patients classified as "severe" by erosion score displayed lower VPAC1 expression levels (p=0.0722) and higher levels of VPAC2 (p=0.0253). <h3>Conclusions</h3> VIP serum levels and VPAC1 and 2 receptors expression are associated with a more severe phenotype in EA patients stratified by SDAI, GDAPh and bone erosion. <h3>References</h3> Firestein GS. Nature. 2003;423(6937):356–61. Martínez C, Ortiz AM, Juarranz Y, et al. PloS one. 2014;9(1):e85248. Seoane IV, Ortiz AM, Piris L, et al. PloS one. 2016;11(2):e0149141. Aletaha D, Smolen J. Clin Exp Rheumatol. 2005;23(5 Suppl 39):S100–8. <h3>Acknowledgements</h3> This work has been supported by Instituto de Salud Carlos III, Spain, cofinanced by FEDER, European Union: RETICS program, Red de Investigaciόn en Inflamaciόn y Enfermedades Reumáticas (RD16/0012/0008 (RPG) and RD16/0012/0011 (IGA) and the projects PI12/00758 (RPG), PI14/00477 (CMM) and PI14/00442 (IGA). <h3>Disclosure of Interest</h3> None declared