title: A 35-year trend analysis for back pain in Austria: the role of obesity.
abstract: BACKGROUND
  The prevalence of back pain is constantly increasing and a public health problem of high priority. In Austria there is a lack of empirical evidence for the development of back pain and its related factors. The present study aims to investigate trends in the prevalence of back pain across different subpopulations (sex, age, obesity).
  
  
  METHODS
  A secondary data analysis based on five nationally representative cross-sectional health surveys (1973-2007) was carried out. Face-to-face interviews were conducted in private homes in Austria. Subjects aged 20 years and older were included in the study sample (n = 178,818). Obesity was defined as BMI≥30 kg/m2 and adjusted for self-report bias. Back pain was measured as the self-reported presence of the disorder.
  
  
  RESULTS
  The age-standardized prevalence of back pain was 32.9% in 2007; it was higher among women than men (p<0.001), higher in older than younger subjects (p<0.001) and higher in obese than non-obese individuals (p<0.001). During the investigation period the absolute change in the prevalence of back pain was +19.4%. Among all subpopulations the prevalence steadily increased. Obese men showed the highest increase of and the greatest risk for back pain.
  
  
  CONCLUSIONS
  These results help to understand the development of back pain in Austria and can be used to plan controlled promotion programs. Further monitoring is recommended in order to control risk groups and plan target group-specific prevention strategies. In Austria particular emphasis should be on obese individuals. We recommend conducting prospective studies to confirm our results and investigate causal relationships.
authors.affiliation: Medical University of Graz, Institute of Social Medicine and Epidemiology, Graz, Austria.
authors.forename: Franziska
authors.initials: F
authors.lastname: Großschädl
authors.affiliation: Medical University of Graz, Institute of Social Medicine and Epidemiology, Graz, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Freidl
authors.affiliation: Medical University of Graz, Institute of Social Medicine and Epidemiology, Graz, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Rásky
authors.affiliation: Medical University of Graz, Institute of Social Medicine and Epidemiology, Graz, Austria.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Burkert
authors.affiliation: University of Graz, Institute of Sociology, Graz, Austria.
authors.forename: Johanna
authors.initials: J
authors.lastname: Muckenhuber
authors.affiliation: Medical University of Graz, Institute of Social Medicine and Epidemiology, Graz, Austria.
authors.forename: Willibald J
authors.initials: WJ
authors.lastname: Stronegger
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D001416:Back Pain / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D015995:Prevalence; D012737:Sex Factors