title: Low back pain in drivers exposed to whole body vibration: analysis of a dose-response pattern.
abstract: OBJECTIVE
  Analysis of a dose-response pattern between exposure to whole body vibration (WBV) and low back pain (LBP) in a group of drivers.
  
  
  METHODS
  This study assessed individual factors, work-related risk factors, various LBP outcome measures and LBP disability in a group of drivers (n = 571) approached at baseline (T0), as well as the WBV magnitude of a representative sample of their vehicles (n = 49), at T0 and at 1-year follow-up (T1). Data were collected using a self-administered questionnaire and actual field measurements according to ISO 2631-1. The magnitude and duration of vibration exposure and a variety of daily and cumulative WBV-exposure measures were calculated for each driver.
  
  
  RESULTS
  229 drivers (40.1%) completed both questionnaires (T0 and T1). The magnitude of WBV was comparable over time. Depending on the LBP outcome, various individual factors (marital status, back trauma and smoking) and work-related risk factors (previous job with heavy physical loading, lifting, bending and the physical risk index) related significantly to onset (all, p<0.05). After adjusting for these contributing factors, the study found a significant trend (an increase in odds ratios of developing LBP with an increase in WBV exposure) for driving-related LBP with daily driving time (p<0.03), and the cumulative measures total hours of exposure (p<0.01), root sum of squares at total dose (p<0.05) and root sum of quads at total dose (p<0.01). No significant trend was found for 12-month LBP. No analysis on a possible dose-response pattern could be derived for either LBP intensity or LBP disability, due to low prevalence.
  
  
  CONCLUSIONS
  The investigation found a dose-response pattern between WBV exposure and driving-related LBP. No indication of a dose-response pattern was found between WBV exposure and 12-month LBP. Although this dose-response pattern is only an indication, these findings imply that WBV exposure might contribute to the onset of driving-related LBP.
authors.affiliation: Coronel Institute of Occupational Health, Academic Medical Center (AMC), Meibergdreef 9, PO Box 22700, 1100 DE Amsterdam, The Netherlands. i.j.tiemessen@amc.uva.nl
authors.forename: I J H
authors.initials: IJ
authors.lastname: Tiemessen
authors.forename: C T J
authors.initials: CT
authors.lastname: Hulshof
authors.forename: M H W
authors.initials: MH
authors.lastname: Frings-Dresen
mesh_terms: D000328:Adult; D001334:Automobile Driving; D004812:Epidemiologic Methods; D006801:Humans; D017116:Low Back Pain / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles / Q000706:statistics & numerical data; D009426:Netherlands / Q000453:epidemiology; D009784:Occupational Diseases / Q000453:epidemiology / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D014732:Vibration / Q000009:adverse effects*