title: The Association Between Body Mass Index (BMI) and Back or Leg Pain in Patients With Spinal Conditions: Results from the Genodisc Study.
abstract: METHODS
  A prospective observational study.
  
  
  OBJECTIVE
  The aim of this study was to identify the relationship between obesity, quantified by body mass index (BMI), and both back and leg pain in spinal patients.
  
  
  BACKGROUND
  Obesity and back pain are massive public health problems. Given the poor correlation between pain and a pathological change in the spine, further investigation is required into other, nonpathological predictors such as obesity.
  
  
  METHODS
  The Genodisc Study was one of the largest cross-sectional studies of patients presenting to tertiary spinal units and recruited from six centers in four European countries. In total, 2636 patients were recruited over a 5-year period between 2008 and 2013. Both back and leg pain were scored by patients in the range of 0 to 10. Linear regression was used to model the relationship between BMI and pain. Potential confounders included in the model were age, Zung Depression score, episodes of sport, gender, disability benefit, family history, previous surgery, smoking status, work type, clinical diagnosis, and relevant comorbidities. Back and leg pain outcomes were modeled separately.
  
  
  RESULTS
  The study included 1160 men and 1349 women with a mean age of 50.9 years and mean BMI of 27.2 kg/m. In our fully adjusted model, a 5-point increase in BMI was associated with greater leg [0.19 units (95% confidence interval 0.08-0.31)] but not back [0.10 units (95% CI -0.02 to 0.22)] pain scores. Although this relationship was statically significant, given the small magnitude of the relationship, the clinical significance is limited. Similarly, female gender, heavy workload, rheumatoid arthritis, previous spine surgery, and depression were associated with higher back and leg pain.
  
  
  CONCLUSIONS
  In this large observational study of spine patients presenting to tertiary European centers, obesity, as measured by increased BMI, was associated with greater leg pain.
  
  
  METHODS
  2.
authors.affiliation: Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, UK.|Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Trust, Oxford, UK.|Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
authors.forename: Anand Hari
authors.initials: AH
authors.lastname: Segar
authors.affiliation: Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
authors.forename: Jill P G
authors.initials: JPG
authors.lastname: Urban
authors.affiliation: Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, UK.|Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Trust, Oxford, UK.
authors.forename: Jeremy C T
authors.initials: JCT
authors.lastname: Fairbank
authors.affiliation: National Institute of Health Research Musculoskeletal Biomedical Research Unit, University of Oxford, Oxford, UK.|MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton General Hospital, Southampton, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Judge
mesh_terms: D000328:Adult; D000368:Aged; D001416:Back Pain / Q000150:complications* / Q000503:physiopathology; D015992:Body Mass Index; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D010146:Pain / Q000150:complications* / Q000503:physiopathology; D010147:Pain Measurement; D011446:Prospective Studies