Open Access Highly Accessed Research article

Body mass index influences the response to infliximab in ankylosing spondylitis

Sébastien Ottaviani1, Yannick Allanore23, Florence Tubach4, Marine Forien1, Anaïs Gardette1, Blandine Pasquet3, Elisabeth Palazzo1, Marine Meunier2, Gilles Hayem1, Chantal Job-Deslandre2, André Kahan2, Olivier Meyer1 and Philippe Dieudé15

Author affiliations

1 Rheumatology Department, AP-HP, Paris Diderot, Sorbonne Paris Cité University, Bichat Claude Bernard Hospital, 46 rue Henri Huchard, Paris, 75018, France

2 Rheumatology A Department, AP-HP, Paris Descartes University, Cochin Hospital, 27 rue du Faubourg Saint-Jacques, Paris, 75014, France

3 INSERM U1016, Paris Descartes University, Cochin Hospital, 27 rue du Faubourg Saint-Jacques, Paris, 75014, France

4 Epidemiology Biostatistics and Clinical Research Department, AP-HP, INSERM, CIE801, Paris Diderot, Sorbonne Paris Cité University, Bichat Claude Bernard Hospital, 46 rue Henri Huchard, Paris, 75018, France

5 INSERM U699, Paris Diderot, Sorbonne Paris Cité University, Faculté de Médecine Xavier Bichat, 16 rue Henri Huchard, Paris, 75018, France

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Citation and License

Arthritis Research & Therapy 2012, 14:R115  doi:10.1186/ar3841

Published: 14 May 2012

Abstract

Introduction

The excess of adipose tissue in obese individuals may have immunomodulating properties and pharmacokinetic consequences. The aim of this study was to determine whether body mass index (BMI) affects response to infliximab (IFX) in ankylosing spondylitis (AS) patients.

Methods

In 155 patients retrospectively included with active AS, the BMI was calculated before initiation of IFX treatment (5 mg/kg intravenously). After 6 months of treatment, changes from baseline in BASDAI, Visual Analogue Scale (VAS) pain, C-reactive protein (CRP) level, and total dose of nonsteroidal antiinflammatory drug (NSAID) were dichotomized with a threshold corresponding to a decrease of 50% of initial level of the measure, into binary variables assessing response to IFX (BASDAI50, VAS50, CRP50, NSAID50). Whether the BMI was predictive of the response to IFX therapy according to these definitions was assessed with logistic regression.

Results

Multivariate analysis found that a higher BMI was associated with a lower response for BASDAI50 (P = 0.0003; OR, 0.87; 95% CI (0.81 to 0.94)), VAS50 (P < 0.0001; OR, 0.87; 95% CI (0.80 to 0.93)); CRP50 (P = 0.0279; OR, 0.93; 95% CI (0.88 to 0.99)), and NSAID50 (P = 0.0077; OR, 0.91; 95% CI (0.85 to 0.97)), criteria. According to the three WHO BMI categories, similar results were found for BASDAI50 (77.6%, 48.9%, and 26.5%; P < 0.0001), VAS50 (72.6%, 40.4%, and 16.7%; P < 0.0001); CRP50 (87.5%, 65.7%, and 38.5%; P = 0.0001), and NSAID50 (63.2%, 51.5%, and 34.6%; P = 0.06).

Conclusions

This study provides the first evidence that a high BMI negatively influences the response to IFX in AS. Further prospective studies, including assessment of the fat mass, pharmacokinetics, and adipokines dosages are mandatory to elucidate the role of obesity in AS IFX response.