title: Risk factors for back-related disability in the US Army and Marine Corps.
abstract: METHODS
  Matched case-control epidemiological study.
  
  
  OBJECTIVE
  To identify pre-enlistment, demographic, and service-related risk factors for back-related disability in enlisted US soldiers and Marines comparing those who were deployed with those who did not deploy during the service term.
  
  
  BACKGROUND
  Back conditions are a major cause of morbidity and lost work days in both the US working population and military. Back-related conditions are among the most prevalent causes of military disability discharge but little research has been conducted to identify risk factors for back-related disabilities in this population.
  
  
  METHODS
  Cases included enlisted Army and Marine Corps service members evaluated for back-related disability. Controls, frequency matched by year of military entrance and service, were selected from the enlisted service member population. Pre-enlistment demographic and medical characteristics, deployment, and ambulatory care data collected from existing military databases were used. Crude and adjusted odds of back-related disability were modeled using conditional logistic regression.
  
  
  RESULTS
  In adjusted models, service members who were overweight (odds ratio [OR]: 1.17; 95% confidence interval [95% CI]: 1.12-1.23) and obese (OR: 1.35; 95% CI: 1.26-1.44), between ages 25 and 29 years (OR: 1.23; 95% CI: 1.16-1.31), or 30 years or older (OR: 1.43; 95% CI: 1.34-1.52) at military entrance were at increased odds of a back-related disability. History of a back diagnosis at the pre-enlistment medical examination (OR: 1.94; 95% CI: 1.50-2.50) and deploying once (OR: 1.09; 95% CI: 1.05-1.14) were also associated with increased odds of a back-related disability.
  
  
  CONCLUSIONS
  Enlisted soldiers and marines with back-related disabilities were more likely to be older, have a higher body mass index, have a history of pre-enlistment back conditions, and were deployed once, compared with controls without a back-related disability. Additional research is necessary to further examine the complex relationship between deployment to combat zones, onset of musculoskeletal symptoms, and back-related disability in soldiers and marines.
  
  
  METHODS
  4.
authors: *Department of Epidemiology, Preventive Medicine Program, Walter Reed Army Institute of Research, Silver Spring, MD; and †Mission Solutions & Services, ManTech International Corporation, Herndon, VA.
authors: Marlene E
authors: ME
authors: Gubata
authors: Amanda L
authors: AL
authors: Piccirillo
authors: Elizabeth R
authors: ER
authors: Packnett
authors: David W
authors: DW
authors: Niebuhr
authors: Michael R
authors: MR
authors: Boivin
authors: David N
authors: DN
authors: Cowan
mesh_terms: D000328:Adult; D000367:Age Factors; D019567:Back Injuries / Q000175:diagnosis*; D015992:Body Mass Index; D016022:Case-Control Studies; D004185:Disability Evaluation; D006233:Persons with Disabilities; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D012307:Risk Factors; D014481:United States