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Background: Obesity is a common comorbidity that is highly associated with poor social functioning and quality of life in patients with rheumatoid arthritis (RA). It is directly linked to mental health issues and central sensitization to pain, potentially influencing patients' subjective perception of disease activity. Objectives: To analyze the relationship between obesity and patient-reported outcomes (PROs) in long-standing RA, under real-life conditions. Methods: We evaluated data from the REAL study (1), a Brazilian, multicenter, observational cohort of participants aged 18+ years old, meeting the ACR/EULAR (2010) classification criteria for RA. Clinical-epidemiological and laboratorial data were collected in the inclusion visit. Obese (body mass index, BMI ≥ 30 kg/m2) and normal-weight, eutrophic participants (BMI 18.5 to 24.9 kg/m2) were compared. Overweight participants (BMI 25 to 29.9 kg/m2), as belonging in a midway category, were excluded to allow focusing on obesity specifically, to avoid confusion. Bivariate and multivariate analyzes were performed in SPSS 25, using chi-squared and students' t tests, and linear and logistic regression. The study was ethically approved; all participants signed informed consent. Results: Of the 1,115 participants in the REAL study, 654 had their BMI within the eligible ranges of interest, being included in this sub-study, of which 299 (45.7%) were classified as obese, and 355 (54.3%) as eutrophic; 89.4% (n= 585) were female, and 77.2% (n= 505) had positive rheumatoid factor (RF). On average, the participants were 57.1 (SD: 11.8) years old, and had 14.5 (9.6) years of disease duration. Regarding the treatment, 46% were using corticosteroids (n= 301), and 33.3% (n= 218) were on some biological disease-modifying anti-rheumatic drugs (bioDMARD). The mean (SD) score for the simplified disease activity index (SDAI) was 14.7 (13.3), and for the patient-reported RA disease activity index (RADAI): 3.2 (2.2). Table 1 shows the differences between the eutrophic and obese groups in bivariate analyzes. In multivariate analyzes, after adjusting for the covariates sex, RF titers, corticosteroid use, bioDMARD use, and SDAI score, obesity remained as an independent predictor for the following outcomes: joints pain intensity (visual analog scale, VAS, 0-100 mm; β 95%CI: 5.4 1.3-9.5; p=0.011); fatigue (VAS 0-100 mm; β 95%CI: 6.0 1.0-11.0; p=0.018); patient global assessment (PGA) of disease activity (VAS 0-100 mm; β 95%CI: 5.1 1.2-9.0; p=0.011); RADAI (β 95%CI: 0.29 0.04-0.55; p=0.026); Boolean 1.0 remission (OR 95%CI: 0.35 0.13-0.91; p=0.032) and Boolean 2.0 remission (OR 95%CI: 0.40 0.18-0.88; p=0.022). Conclusion: Obese patients with RA, compared to eutrophic ones, exhibited lower frequency of remission as assessed by RADAI and the Boolean criteria (both 1.0 and 2.0), although not based on SDAI. Analyzing the inner components of the Boolean criteria, no significant differences across the groups were observed in the non-patient-reported elements (CRP and physician-led counts of painful and swollen joints), hence the lower rate of Boolean remission in obese patients being mainly driven by PGA. Likewise, the physician global assessment (PhGA, which is part of SDAI) was not significantly different across groups, while other subjective outcomes, such as fatigue and pain intensity, were worse in obese participants. Overall, obesity was associated with worse scores on PROs, even when no clinical evidence for higher, objective, inflammatory activity was found. In spite of that, obese patients were more exposed to corticosteroids and bioDMARD, potentially indicating overtreatment, and ultimately implying higher management risks and costs in this group. REFERENCES: 1 DA ROCHA CASTELAR-PINHEIRO G. et al. The REAL study: a nationwide prospective study of rheumatoid arthritis in Brazil. Adv Rheumatol, v. 58, n. 1, p. 9, Jun 28 2018. ISSN 2523-3106. Acknowledgements: The authors acknowledge the financial support of the Brazilian Society of Rheumatology. Disclosure of Interests: Mariana Drummond Martins Lima: None declared, Cleandro Albuquerque: None declared, Ana Luisa Bagno de Almeida: None declared, Maria Fernanda Brandão de Resende Guimarães: None declared, Ana Paula Gomides: None declared, Rina Dalva Neubarth Giorgi Personal fees and/or nonfinancial support from AbbVie, Bristol-Myers-Squibb, Eli Lilly, Janssen and UCB, Leticia Pereira: None declared, Sebastiao Radominski Consulting fees, speaking fees and institutional support for clinical trials from AbbVie, Amgen, Bristol-Myers-Squibb, Lilly, Pfizer, and Roche, Consulting fees, speaking fees and institutional support for clinical trials from AbbVie, Amgen, Bristol-Myers-Squibb, Lilly, Pfizer, and Roche, Consulting fees, speaking fees and institutional support for clinical trials from AbbVie, Amgen, Bristol-Myers-Squibb, Lilly, Pfizer, and Roche, Ivanio Pereira: None declared, Alisson Pugliesi: None declared, Paulo Louzada Jr: None declared, Maria de Fátima Sauma: None declared, Karina Bonfiglioli Personal fees and/or nonfinancial support from Abbvie, Boheringer Ingelheim, Bristol-Myers-Squibb, Janssen, Novartis and Roche, Claiton Brenol Personal fees and/or nonfinancial support from AbbVie, Bristol-Myers-Squibb, Janssen, Novartis, Pfizer, Roche and UCB, Licia Mota Personal or institutional support from AbbVie, Janssen, Pfizer and Roche; has delivered speeches at events related to this work and sponsored by AbbVie, Boehringer Ingelheim, GSK, Janssen, Libbs, Lilly, Novartis, Pfizer, Roche, Sandoz, and UCB, Personal or institutional support from AbbVie, Janssen, Pfizer and Roche; has delivered speeches at events related to this work and sponsored by AbbVie, Boehringer Ingelheim, GSK, Janssen, Libbs, Lilly, Novartis, Pfizer, Roche, Sandoz, and UCB, Geraldo da Rocha Castelar Pinheiro: None declared.
Lima et al. (Sat,) studied this question.