POS0568 OBESITY RATES AND BMI ARE SIMILAR IN AGE AND SEX MATCHED RHEUMATOID ARTHRITIS, PSORIATIC ARTHRITIS AND SPONDYLOARTHRITIS PATIENTS
Authors: G. K. Yardimci, B. Farisoğullari, E. C. Bolek, E. Bilgin, E. Duran, G. Ayan, Z. Özsoy, G. Sandal Uzun, L. Kiliç, A. Akdoğan, O. Karadag, Ş. A. Bilgen, S. Kiraz, U. Kalyoncu, A. İ. Ertenli
Journal: Annals of the Rheumatic Diseases (2021)

Background: Obesity has been suggested to be a chronic inflamatory condition and therefore, obesity may be considered as a risk factor for developing immune-mediated diseases, including inflammatory arthritis. In larger biologic registiries, obesity was found frequently in psoriatic arthritis than other inflammatory diseases such as rheumatoid arthritis and spondyloarthritis. [1-4]. However, obesity may be a reason of aging, moreover, there are strong sex differences between those diseases. Objectives: The aim of this study was to evaluate the obesity rates in sex and aged matched patients with inflammatory arthritis before the initation of biological therapy. Methods: HUR-BIO (Hacettepe University Biologic Registry) is a prospective, single center database of biological treatments since 2005 and to date 5635 patients have been recorded. Demographic, clinical and laboratory data before bDMARD of SpA, RA and PsA patients were noted. The patients were divided into two groups: non-obese patients (&lt;30 kg/ m 2 ) and obese (≥30 kg/m 2 ) patients. When investigeting the changes in BMI by diagnosis, the effects of gender and age were adjusted using two-way ANOVA and ANCOVA tests. The selection was made for the gender and age indifferences of the relevant groups by using propensity score. Results: 5059 patients’ (1834 RA, 2741 SpA and 484 PsA) BMI data before the bDMARD treatments were avaliable and analysed. Baseline characteristics of RA, SpA and PsA patients were given in Table 1. 72.3% of the RA patients were seropositive. HLAB27 was positive in 64.7% and 22.9% of the SpA and PsA patients. Anti-TNF therapy was started as first bDMARD in 57.2% of the RA patients, others were started with non-Anti-TNF bDMARDs. In SpA (99.2%) and PsA (100%) patients anti-TNFs were the first biologics. Overall, the proportion of obese patients was significantly higher in RA and PsA than in SpA patients (Table 1) and age and sex affected BMI significantly (p&lt;0.001) (Figure 1). After adjusting age and sex indifference between groups, the difference between the BMI of the patients disappeared (Table 1). Table 1. Baseline characteristics and BMI of the patients RA SpA PsA p All bDMARD patients N 1834 2741 484 Female, n (% ) 1470 (80.2) 1257 (45.9) 334 (69.0) 0.000* Age, years* 52.9±13.4 43.1±11.4 47.4±12.2 0.000* Disease duration, years ¥ 11 (7-17) 8 (5-13) 7 (3-12) 0.000* Body mass index* 29.6 ± 6.5 27.7 ± 5.4 29.2 ± 5.8 0.000* Obesity, n (% ) 811 (44.2) 815 (29.7) 199 (41.1) 0.000* Age and sex matched group N 481 483 484 Female, n (% ) 315 (65.7) 324 (67.1) 334 (69.0) 0.545 Age, years* 47 (36-59) 48 (39-57) 47 (38-56) 0.691 Disease duration, years ¥ 10 (6-15) 5 (5-13) 7 (3-12) 0.000* Body mass index* 28.5 ± 6.1 28.5 ± 5.8 29.2 ± 5.8 0.150 Obesity, n (% ) 183 (38.0) 176 (36.4) 199 (41.1) 0.316 * Mean ±S.D ¥ Median (IQR) Conclusion: Although obesity was more frequently reported in RA and PsA patients, age and gender seemed to be the major factors in the occurrence of this difference rather than inflammatory arthritis subgroups. Therefore, when considering obesity as a factor in the registries, for instance biological registries, sex and age should be kept in mind. References: [1]Højgaard, P., et al., The influence of obesity on response to tumour necrosis factor-α inhibitors in psoriatic arthritis: results from the DANBIO and ICEBIO registries. Rheumatology (Oxford), 2016. 55 (12): p. 2191-2199. [2]Liu, Y., et al., Impact of Obesity on Remission and Disease Activity in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis. Arthritis Care Res (Hoboken), 2017. 69 (2): p. 157-165. [3]Moroni, L., N. Farina, and L. Dagna, Obesity and its role in the management of rheumatoid and psoriatic arthritis. Clin Rheumatol, 2020. 39 (4): p. 1039-1047. [4]Zurita Prada, P.A., et al., Influence of smoking and obesity on treatment response in patients with axial spondyloarthritis: a systematic literature review. Clin Rheumatol, 2020. Figure 1. BMI regarding to sex and diseases subtypes Disclosure of Interests: None declared