POS0568 OBESITY RATES AND BMI ARE SIMILAR IN AGE AND SEX MATCHED RHEUMATOID ARTHRITIS, PSORIATIC ARTHRITIS AND SPONDYLOARTHRITIS PATIENTS

Abstract

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 (<30 kg/ m2) and obese (≥30 kg/m2) 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<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 patientsRASpAPsApAll bDMARD patientsN18342741484Female, n (%)1470 (80.2)1257 (45.9)334 (69.0)0.000*Age, years*52.9±13.443.1±11.447.4±12.20.000*Disease duration, years¥11 (7-17)8 (5-13)7 (3-12)0.000*Body mass index*29.6 ± 6.527.7 ± 5.429.2 ± 5.80.000*Obesity, n (%)811 (44.2)815 (29.7)199 (41.1)0.000*Age and sex matched groupN481483484Female, n (%)315 (65.7)324 (67.1)334 (69.0)0.545Age, years*47 (36-59)48 (39-57)47 (38-56)0.691Disease duration, years¥10 (6-15)5 (5-13)7 (3-12)0.000*Body mass index*28.5 ± 6.128.5 ± 5.829.2 ± 5.80.150Obesity, 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.