Identification and prevention of work-related diseases and premature incapacity.

In many cases, the increasing knowledge about the causes of occupational diseases has led to improved preventive actions at the working place. This made it possible to achieve a general decrease in the incidence of occupational diseases--except for some illnesses such as asbestos-related and obstructive lung diseases. An opposite trend can be noticed in the field of work-related illnesses, which especially includes cardiovascular, psychiatric and psychovegetative diseases, and musculoskeletal disorders. In contrast to the occupational diseases, in this context work factors are only of less importance and interact with intrapersonal, social and environmental aspects. Since the associations between the working world and the disease are normally too weak due to the multiple causes involved, what is therefore required for researching these multifactorial relationships are most sensitive epidemiological examination methods including large populations and at the same time avoiding or controlling bias and confounding. Most of the recent studies are based on secondary evaluations of already existing data (premature incapacity, inability to work, results from special preventive checks at the working place). Although this leads to large populations, a considerable bias is caused at the same time since these data in most cases are collected for administrative purpose rather than for epidemiological reasons. Moreover, when looking at the different load factors, only the work aspects are mainly taken into consideration, which leads to considerable confounding due to the omitted other concurring causes. Thus, most of the associations discovered so far are not strong enough to allow for a general deduction of special preventive measures at the working place. For further investigation of these relationships, prospective cohort and intervention studies are therefore required.