title: Which is the best cutoff of body mass index to identify obesity in female patients with rheumatoid arthritis? A study using dual energy X-ray absorptiometry body composition.
abstract: BACKGROUND
  Standard anthropometric measures used to diagnose obesity in the general population may not have the same performance in patients with rheumatoid arthritis.
  
  
  OBJECTIVE
  To determine cutoff points for body mass index (BMI) and waist circumference (WC) for detecting obesity in women with rheumatoid arthritis (RA) by comparing these standard anthropometric measures to a dual-energy x-ray absorptiometry (DXA)-based obesity criterion.
  
  
  METHODS
  Adult female patients with more than six months of diagnosis of RA underwent clinical evaluation, with anthropometric measures and body composition with DXA.
  
  
  RESULTS
  Eighty two patients were included, mean age 55±10.7 years. The diagnosis of obesity in the sample was about 31.7% by BMI, 86.6% by WC and 59.8% by DXA. Considering DXA as golden standard, Cutoff points were identified for anthropometric measures to better approximate DXA estimates of percent body fat: for BMI value ≥ 25kg/m2was the best for definition of obesity in female patients with RA, with sensitivity of 80% and specificity of 60%. For WC, with 80% of sensitivity and 35% of specificity, the best value to detect obesity was 86cm.
  
  
  CONCLUSIONS
  A large percentage of patients were obese. The traditional cutoff points used for obesity were not suitable for our sample. For this female population with established RA, BMI cutoff point of 25kg/m2and WC cutoff point of 86cm were the most appropriate to detect obesity.
authors.affiliation: Serviço de Reumatologia, Hospital das Clínicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil. Electronic address: mfbresende@yahoo.com.br.
authors.forename: Maria Fernanda B Resende
authors.initials: MF
authors.lastname: Guimarães
authors.affiliation: Serviço de Reumatologia, Hospital das Clínicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil.
authors.forename: Maria Raquel
authors.initials: MR
authors.lastname: da Costa Pinto
authors.affiliation: Faculdade de Tecnologia em Radiologia, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil.
authors.forename: Renata G Santos Couto
authors.initials: RG
authors.lastname: Raid
authors.affiliation: Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil.
authors.forename: Marcus Vinícius Melo de
authors.initials: MV
authors.lastname: Andrade
authors.affiliation: Serviço de Reumatologia, Hospital das Clínicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil; Departamento do Aparelho Locomotor, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brasil.
authors.forename: Adriana Maria
authors.initials: AM
authors.lastname: Kakehasi
keywords: Artrite reumatoide; Body composition; Body mass index; Bone densitometry; Composição corporal; Densitometria óssea; Obesidade; Obesity; Rheumatoid arthritis; Índice de massa corporal