The relative contribution of work exposure, leisure time exposure, and individual characteristics in the onset of arm-wrist-hand and neck-shoulder symptoms among office workers

Purpose: To identify the risk factors for the onset of arm-wrist-hand and neck-shoulder symptoms among office workers and to estimate the relative contribution of these risk factors by calculating Population Attributable Fractions (PAFs). Methods: A prospective cohort study was conducted among 1951 office workers with a follow-up duration of 2 years. Data on self-reported risk factors were collected at baseline and after 1 year of follow-up. Every 3 months, the occurrence of upper extremity symptoms was assessed using questionnaires. PAFs for individual risk factors were estimated based on Rate ratios (RRs) obtained from Poisson regression using Generalized Estimation Equations. Results: Previous disabling symptoms were identified as the most important risk factor for the onset of arm-wrist-hand and neck-shoulder symptoms. Modifiable risk factors for arm-wrist-hand symptoms with relatively large PAFs were: at least 4 h per day of self-reported computer use at work, high level of overcommitment, and low task variation and for neck-shoulder symptoms: supporting the arms during keyboard use and at least 4 h per day of self-reported mouse use at work. Compared to having 0 or 1 risk factor, the RR for arm-wrist-hand symptoms increased to 6.2 (95% CI 3.7-10.5) for having 5-7 potentially modifiable risk factors and for neck-shoulder symptoms to 3.0 (95% CI 2.1-4.4) for having 4 or 5 potentially modifiable risk factors. Conclusion: Preventive interventions at the population level should be aimed at changing modifiable risk factors with large PAFs. At the individual level, preventive interventions should be aimed at changing multiple modifiable risk factors simultaneously. © Springer-Verlag 2011