AB0734 CHANGES IN HEIGHT AND BODY MASS INDEX OVER TIME IN PATIENTS WITH AXIAL SPONDYLOARTHITIS, TREATED WITH TUMOR NECROSIS FACTOR-A INHIBITORS

Background: Monitoring of height and body mass index (BMI) is an important for patients with axial spondyloarthritis (axSpA). Reduction of height not only reflects spine remodeling, but affects various indexes, such as BMI (fig.1). However, BMI calculations assume that the adult patient‘s height is a constant. Therefore these calculations may be inaccurate in patients whose height is susceptible to decrease. Objectives: To evaluate changes in height and BMI over time in patients with axSpA, treated with tumor necrosis factor-α inhibitors (iTNF-α). Methods: The study included 51 patients with axSpA (ASAS criteria 2009). All the patients were treated with iTNF-α for one and > years. The patient’s height and weight measured before the beginning TNF-α inhibitors and during the treatment. Only patients with stable weight (variability ± 2.0 kg from baseline) were included in the study. Results: Mean age of axSpA patients at baseline was 40.22±13.51, 38 (74.5%) were male, disease duration 12.77±6.82, duration of TNF-α inhibitors treatment 5.64±2.21 years, all the patients had inactive disease. In 19 patients with axSpA diagnostic delay was 8 years. Patients’ height varied between 1.55 – 1.92 m (average height 1.73±0.07 m). Male’s mean height was 1.78±0.05 m, women’s – 1.63±0.05 m. Height decrease over time in patients with axSpa was 3.74±1.83 cm (from 1.0 to 15.0 cm). Maximal decrease in height was shown in patients with 10 years after the first symptoms emerged. Mean weight in patients who had height loss was 79.75±12.7 kg. Among patients who had decrease of height and stable body mass the difference between BMI at subsequent measurement and the time of treatment initiation (ΔBMI) was 1.15 kg/m2: BMI at baseline = 26.25±3.34 kg/m2, over time of observation BMI = 27.39±3.38 kg/m2). Conclusion: Height loss in axSpA is significant even in patients with inactive disease. Height loss affects BMI calculation that could lead to overestimation of cardiovascular risk, obesity and could change all of the BMI-dependent areas. Correction of BMI calculation for the patients with unstable height is needed. Disclosure of interests: Elizaveta Vasilenko: None declared, Olga Nikolaeva: None declared, anna Dadalova: None declared, Ekaterina Gaydukova: None declared, V Mazurov Grant/research support from: JSC BIOCAD, inna Gaydukova Grant/research support from: JSC BIOCAD, Speakers bureau: paiment from Pfizer, Novartis, abbvie, Biocad, Selgene, MSD, Sanofy not exceed 10 000 euros