title: Prevalence and physical determinants of low back pain in a rural Chinese population.
abstract: METHODS
  This was a community-based cross-sectional study that is part of an ongoing study of genetics and osteoporosis.
  
  
  OBJECTIVE
  To estimate the 1-year self-reported prevalence of low back pain (LBP); and to assess the association between physical exposures (occupation, physical stress, and vibration) and LBP in a rural Chinese population. This study also explored how these associations change when individuals with LBP report additional pains in other parts of the body.
  
  
  BACKGROUND
  Little is known about the prevalence and determinants of LBP in rural developing populations, even though approximately half of the world's population, mostly from the developing world, is engaged in agriculture, a known strenuous activity.
  
  
  METHODS
  Families with at least three participating siblings residing in the surrounding rural region of Anqing city, Anhui Province, China, were invited to participate in the study through public announcements and direct invitations by village physicians. A questionnaire including demographics, physical exposures, and musculoskeletal pain was administered to 13,965 men and women (age, 25-64 years). Generalized estimating equations were used to estimate LBP prevalence and examine associations between LBP and physical exposures.
  
  
  RESULTS
  The 1-year prevalence of LBP was 64%. Twenty-five percent reported no pain at any body site. Women had higher prevalence of LBP than men across all age groups. Being a farmer, reporting moderate or heavy physical stress, and having had former or current exposures to vibration were positively associated with LBP (P < 0.05). Physical exposures were also associated with cases of LBP combined with other musculoskeletal pains, and generally, the more pains individuals reported, the more likely it was that they were farmers and were exposed to vibration.
  
  
  CONCLUSIONS
  A high prevalence of LBP and LBP with additional musculoskeletal pain existed in this rural Chinese sample. We found evidence of a link between physical exposures and LBP, and LBP with additional musculoskeletal pain. Further understanding of the characteristics and risk factors of LBP in rural developing areas is needed.
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA.
authors.forename: Lope H
authors.initials: LH
authors.lastname: Barrero
authors.forename: Yi-Hsiang
authors.initials: YH
authors.lastname: Hsu
authors.forename: Henry
authors.initials: H
authors.lastname: Terwedow
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Perry
authors.forename: Jack T
authors.initials: JT
authors.lastname: Dennerlein
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Brain
authors.forename: Xiping
authors.initials: X
authors.lastname: Xu
mesh_terms: D000328:Adult; D000383:Agriculture / Q000706:statistics & numerical data; D044466:Asian People / Q000706:statistics & numerical data*; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000150:complications / Q000208:ethnology* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000150:complications / Q000208:ethnology / Q000209:etiology; D009784:Occupational Diseases / Q000208:ethnology*; D010146:Pain / Q000150:complications / Q000453:epidemiology / Q000208:ethnology; D005082:Physical Exertion; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014732:Vibration / Q000009:adverse effects*