Predictors of occupational low back disability: implications for secondary prevention

Over the past decade, studies have identified a combination of demographic, physical/medical, ergonomic, and psychosocial factors in the development of work disability related to occupational low back pain. Using such data on disability risk factors, investigators have begun to develop risk identification and disability prevention programs. As part of an ongoing effort to develop a secondary prevention program, the present case-control study identified the relative contribution of demographic, physical demand, physical fitness, as well as occupational and individual psychosocial variables to back-related work disability in the US Army. Soldiers (n = 174) diagnosed with a lumbosacral strain and medically discharged from the Army were compared with non-disabled controls (n = 173). Dependent measures were obtained from the US Army Health Risk Appraisal (HRA). For cases, these data pre-dated disability determination by 1 to 3 years. For controls, the HRA was completed during the same time period. Significant predictors of low back disability were: age (odds ratio [OR] = 1.13 per year), lower rank (E2/E3) (OR = 4.08/OR = 3.02), infrequent aerobic exercise (OR = 2.2), higher work stress (OR = 2.71), worries (OR = 2.17), and lower social support (OR = 5.07). The model correctly classified 73.13% of all subjects. These results highlight the importance of considering age, status level in the organization, frequency of aerobic exercise, occupational stress, general worries, and social support for the early detection of soldiers at increased risk for back-related disability. Additionally, the findings support past research indicating the multivariate nature of work disability and emphasize the importance of considering such factors in future secondary prevention efforts.