title: Obesity reduces the drug survival of second line biological drugs following a first TNF-α inhibitor in rheumatoid arthritis patients.
abstract: OBJECTIVE
  The aim of this study was to assess whether body mass index (BMI) affects clinical outcomes in rheumatoid arthritis (RA) patients starting a second line biological drug after failure of a first TNF-α blocker.
  
  
  METHODS
  From a longitudinal cohort, we analyzed 292 RA patients (66 obese, 109 overweight, and 117 normal-weight) treated with a first ever anti-TNF-α drug. Patients discontinuing the therapy were followed-up if began a second biological drug. Drug survival, by Kaplan-Meier life analysis, and 12 months disease remission based on the 28-joint Disease Activity Score (DAS28) were assessed for either course of biologics. The baseline predictors of clinical outcomes were assessed by Cox regression analysis.
  
  
  RESULTS
  Survival of the first anti-TNF-α drug was lower in obese (39.4%) than in normal-weight (49.1%) patients, but the difference was not statistically significant. Obese patients had the highest hazard to discontinue the first anti-TNF-α drug (HR 1.64, 1.02-2.62 95% IC, P=0.04), and the lowest percentage of DAS28-based disease remission at 12 months (P=0.04). In 97 (37 normal-weight, 36 overweight, 24 obese) patients who started a second non-anti-TNF-α biological drug, persistence on therapy was significantly lower in obese (43.5%) than in normal-weight (80%, P=0.04) group, and again obesity significantly predicted drug discontinuation (HR 2.9, 1.08-8.45 95% IC, P=0.04). Significantly, less obese patients attained a disease remission (12%, P=0.004) at 12 months.
  
  
  CONCLUSIONS
  Our study provides evidence that obese RA patients poorly respond to second line non-anti-TNF-α drugs after failure of a first TNF-α inhibitor.
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: florenzo.iannone@uniba.it.
authors.forename: Florenzo
authors.initials: F
authors.lastname: Iannone
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: rosalinda.fanizzi@hotmail.it.
authors.forename: Rosalinda
authors.initials: R
authors.lastname: Fanizzi
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: notarnicola.antonella@gmail.com.
authors.forename: Antonella
authors.initials: A
authors.lastname: Notarnicola
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: crescenzio.scioscia@uniba.it.
authors.forename: Crescenzio
authors.initials: C
authors.lastname: Scioscia
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: marynelli@libero.it.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Anelli
authors.affiliation: Interdisciplinary Department of Medicine (DIM), Rheumatology Unit, Medical School, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy. Electronic address: giovanni.lapadula@uniba.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Lapadula
mesh_terms: D000368:Aged; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D015992:Body Mass Index; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D012074:Remission Induction; D012189:Retrospective Studies; D017211:Treatment Failure; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D018501:Antirheumatic Agents; C439524:TNF protein, human; D014409:Tumor Necrosis Factor-alpha
keywords: Adalimumab; Body mass; Etanercept; Infliximab; Rituximab