Stress responses in low-status jobs and their relationship to health risks: musculoskeletal disorders.

Conditions typical of many low-status jobs are known to induce elevated stress. In keeping with this, blue-collar workers show elevated psychophysiological stress levels both during and after work compared with workers in more stimulating and flexible jobs. Health-related behaviors, such as cigarette smoking and drug abuse, that are known to contribute to the social gradient in health, can be seen as ways of coping with a stressful work situation in order to get short-term relief. Negative emotional states associated with low-status jobs, combined with a lack of economic resources, are also likely to reduce the individual's motivation to seek proper medical treatment and, thus, increase the risk that transient symptoms develop into chronic illness. With regard to musculoskeletal disorders, it is well documented that physically monotonous or repetitive work is associated with an increase in neck, shoulder, and low back pain problems. However, recent studies also report an association between psychosocial factors and muscle pain syndromes. Possible mechanisms explaining these findings involve the assumption that psychological stress may induce sustained activation of small, low-threshold motor units that may lead to degenerative processes, damage, and pain. Analysis of short periods of very low muscular electrical activity (EMG gaps) shows that female workers with a high frequency of EMG gaps seem to have less risk of developing myalgia problems than do workers with fewer gaps. Stress induced by psychosocial conditions at work, which is usually more lasting than that resulting from physical demands, may prevent the individual from shutting off their physiological activation and reduces the time for rest and recovery. In the modern work environment, with strong emphasis on a high work pace, competitiveness, and efficiency, it is possible that lack of relaxation is an even more important health problem than is the absolute level of contraction or the frequency of muscular activation.