SAT0081 BOTH OVERFAT AND MYOPENIA ARE ASSOCIATED WITH PHYSICAL DYSFUNCTION IN RHEUMATOID ARTHRITIS PATIENTS
Authors: Chutao Chen, Jian-Zi Lin, Lijuan Yang, LI Qian-Hua, MA Jianda, Le-Feng Chen, Yingqian Mo, Lie Dai
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Comprehensive disease control has been recommended by EULAR guidelines for rheumatoid arthritis (RA) which includes simultaneous achievement of stringent control of the signs and symptoms of inflammation, the absence of radiographic progression and normal physical function. Identifying those patients at high risk of disability at a sufficiently early stage of their disease course presents a major challenge. The associations of body mass index (BMI) and body composition (BC) with physical activity function in RA patients still obscure. <h3>Objectives:</h3> To investigate the characteristics of BC and BMI in RA patients and their association with physical activity function. <h3>Methods:</h3> Consecutive RA patients were recruited and clinical data including disease activity, function and radiographic assessment were collected. BC was assessed by bioelectric impedance analysis. Overfat was defined by body fat percentage (BF%) as ≥25% for men and ≥35% for women. Myopenia was defined by appendicular skeletal muscle mass index (ASMI) ≤7.0kg/m<sup>2</sup> in men and ≤5.7kg/m<sup>2</sup> in women. Subjects were categorized by BMI as underweight (BMI&lt;18.5 kg/m<sup>2</sup>), normal weight (18.5 kg/m<sup>2</sup>≤BMI&lt;24 kg/m<sup>2</sup>), overweight (24 kg/m<sup>2</sup>≤BMI&lt;28 kg/m<sup>2</sup>) and obese (BMI≥28 kg/m<sup>2</sup>) according to Chinese criteria. Physical dysfunction was defined by HAQ-DI≥0.5. <h3>Results:</h3> There were 516 RA patients (mean age 49.8±12.9 years old with 83% women) recruited, and 37% with physical dysfunction. Compared with those with normal physical function, RA patients with physical dysfunction were older with longer disease duration, and had higher disease activity indicators including timing of morning stiffness, 28TJC, 28SJC, PtGA, PrGA, PainVAS, ESR, CRP, DAS28-CRP, SDAI and CDAI, as well as higher radiographic assessment including mTSS, JSN subscore and JE subscore (all <i>P</i>&lt;0.05). As for BMI and BC, RA patients with physical dysfunction had higher BF% (mean 31.05% vs. 29.02%, <i>P</i>=0.007) and prevalence of overfat (44% vs. 27%, <i>P</i>&lt;0.001), lower ASMI (mean 5.73 vs. 6.11, <i>P</i>&lt;0.001) and higher prevalence of myopenia (55% vs. 38%, <i>P</i>&lt;0.001) than those with normal physical function, while no difference in BMI between two groups. After adjustment confounding factors, multivariate logistic regression analysis showed overfat (<i>OR</i>=2.990, 95%<i>CI</i>: 1.695-5.274) and myopenia (<i>OR</i>=1.960, 95%<i>CI</i>: 1.191-3.225) were positively associated with physical dysfunction respectively. Further compared with patients with normal fat, patients with overfat had significantly higher rates of dysfunction of all eight physical activities including dressing, rising, eating, walking, hygiene, reaching, griping and activities respectively (all P&lt;0.01), with the highest rate 57.5% in eating dysfunction and the lowest rate 38.6% in dressing dysfunction. Comparisons between patients with and without myopenia showed similar results with the highest rate 52.4% in eating dysfunction and the lowest rate 37.7% in rising dysfunction in those with myopenia. <h3>Conclusion:</h3> Overfat and myopenia are present in near half RA patients with physical dysfunction which are associated with dysfunction of all eight physical activities especially eating. <h3>Acknowledgement:</h3> This work was supported by National Natural Science Foundation of China (no. 81671612 and 81801606), Guangdong Natural Science Foundation (no. 2017A030313576, 2017A030310236 and 2018A030313541) and Guangdong Medical Scientific Research Foundation (no. A2017109) <h3>Disclosure of Interests:</h3> None declared