2010 Volume 25 Pages 14-18
Health disparities among occupational classes have been observed constantly since the Industrial Revolution. These disparities are widening in recent years. The importance of occupational stress has drawn close attention since it was pointed out that psychosocial characteristics of jobs could explain the health disparities across occupational classes. First, the uneven distribution of stressors among occupational classes may explain the uneven distribution of health problems. This is known as the 'mediation mechanism.' With this, workers in lower occupational classes are more exposed to occupational stress than those in upper occupational classes. Although quantitative/qualitative workloads are not always heavier in lower classes, the higher one's position is, the higher the reward and the availability of control, support and other resources. There is evidence that the statistical adjustment of workers' control over their jobs significantly reduces the relative risk of coronary heart diseases occurrence among workers in lower occupational classes as compared to those in higher occupational classes. Second, it has also been observed that the effect of occupational stress on health is greater in lower than higher occupational classes or, alternatively, that a significant effect on health from stress is found only in lower occupational classes. The effect explained by the interaction between low occupational class and occupational stress is known as the 'modification mechanism' or 'modification effect.' Regarding the interaction between occupational class/occupational stress and health problems, further studies are necessary among diverse work sites and a wider range of occupations. They should evaluate a more permanent effect with longer follow-up. Employing several-wave panel design would be fruitful because reciprocal causal relationships will be evaluated more precisely.