Background In RA, being overweight or obese has previously been shown to be associated with worse clinical outcomes (1, 2), yet also less radiographic damage (2, 3).
Objectives To confirm if body mass index (BMI) is associated with worse clinical disease activity or inversely associated with radiographic outcomes in early RA.
Methods BMI, categorized as normal (<25, n=141), overweight (25–29.9, n=74), and obese (≥30, n=43), was available in 258 patients who were enrolled in the Swedish pharmacotherapy (SWEFOT) trial. After initial methotrexate for 3 months, non-responders were randomized to triple therapy or anti-TNF therapy, while responders continued on methotrexate. Disease activity (DAS28), functional impairment (HAQ), VAS-pain, and radiographic damage (Sharp van der Heijde score, SHS) were evaluated regularly. Here, results are shown at 24 months of follow-up.
Results Treatment allocation and baseline outcome measures did not differ across the BMI categories. In a dose-response manner, higher BMI at baseline was associated with worse clinical outcomes over 24 months (DAS28, HAQ, and VAS-pain) (Table). Patients with normal (58%) or overweight (50%) BMI had a proportionally greater chance of attaining 24-month clinical remission (DAS28<2.6) than obese patients (23.1%) (OR 3.2 [95% CI 1.6–6.3], p<0.001; OR 2.2 [95% CI 1.2–4.1], p=0.007, respectively). Among absolute radiographic scores, no significant differences were observed, yet radiographic progression (ΔSHS≥1, baseline-24 months) was halted more frequently (56.3%) among obese patients than normal/overweight patients combined (37.6%) (OR 1.9 [95% CI 1.0–3.6], p=0.049) (obese vs. normal (40%), OR 1.7 [95% CI 0.9–3.1], p=0.101; obese vs. overweight (32.7%), OR 1.8 [95% CI 1.1–3.2], p=0.032).
Conclusions Obesity at diagnosis was found to be a strong predictor of worse long-term clinical outcomes in early RA – including disease activity, functional impairment, and pain; thus confirming previous findings. Nonetheless – as has also been previously shown – obesity was associated with a better chance of halting radiographic progression.
Sandberg ME, et al. Ann Rheum Dis. 2014 Nov;73(11):2029–33;
Vidal C, et al. J Rheumatol. 2015 Dec;42(12):2261–9;
Baker JF, et al. Ann Rheum Dis. 2014 Nov;73(11):1923–8
Disclosure of Interest A. Levitsky: None declared, S. Saevarsdottir: None declared, K. Brismar: None declared, K. Hambardzumyan: None declared, C. Lourdudoss: None declared, R. van Vollenhoven Grant/research support from: AbbVie, BMS, GSK, Pfizer, Roche, and UCB, Consultant for: AbbVie, Biotest, BMS, Crescendo, GSK, Janssen, Lilly, Merck, Pfizer, Roche, UCB, and Vertex