Epidemiology and Risk Factors of Work-Related Low Back Pain

Abstract

Objects and methods of research. Of the 580 employees of a petrochemical plant, 507 people went through survey for low back pain using the Nordic questionnaire. In the prospective part of the study, 188 workers without any back problems during 12 months before the study were followed up for 6 and 12 months using the same questionnaire. Physical load at work place, age, gender, body mass index (BMI), smoking, and gene PARK2 polymorphism were regarded as potential risk factors. 177 workers provided buccal epithelium for investigation of rs926849 polymorphism A/G in the gene PARK2 by real-time PCR.The results of the study and their discussion. One-year prevalence of low back pain was 38.7% (95% CI 33.6–42.3%), and the incidence of new cases was 20.7% (95% CI 15.3–27.4%).In the presence of the genotype AA the probability of developing the low back pain in the group of up to 30 years were as high as in the group of 30 years and older: OR 0,99 (95% CI 0.29–4.52). For the low back pain with reduction of physical activity or disability, in the presence of AA genotype risk of such pain in workers aged 30 years and older was significantly higher than in the younger group: OR 1.86 (95% CI 1.03–3.57). The probability of low back pain was highest in the simultaneous presence of risk factors such as AA genotype and body mass index 25 kg/m² and more: OR 3,83 (95% CI 2.34–4.88) for all cases of low back pain, OR 10.0 (95% CI 5.04–19.85) for low back pain with reduction of physical activity or disability.Occupational risk factors of high significance (after controlling for non-occupational risk factors and their interactions) were revealed: fixed working posture of more than 25% of the work shift: OR 4.8 (95% CI 1.57–14.69), high dynamic physical load: OR 1.48 (95% CI 0.67– 3.26), as well as high physical load in general: OR 2.96 (95% CI 0.72–12.18). For the low back pain with reduction of physical activity or disability the structure of the risk factors was the same, while the odds ratios were higher and confidence intervals did not include 1.0.Conclusion.The following risk factors of work-related low back pain have been revealed: the age (30 years and older), overweight, genetic predisposition, namely the polymorphism of the PARK2 gene, high physical load, predominantly a fixed working posture of more than 25% of the work shift, and dynamic physical load. It has been shown that interactions of the factors «age» and «genotype», as well as «BMI» and «genotype» should be considered for better understanding of the structure of risk factors of work related low back pain.