Impact of working life patterns on life span
In early 2008, the Austrian Institute for Economic Research published its findings on the impact of different employment and working life patterns on the life span of workers. The study looks at the effects of doing heavy work during night shifts on life expectancy and focuses particular attention on data relating to men born from 1924 to 1949. Moreover, it reveals interesting and sometimes unexpected outcomes regarding working conditions, income levels and unemployment.
About the study
In March 2008, the Austrian Institute for Economic Research (Österreichisches Institut für Wirtschaftsforschung, WIFO) published the findings of its recent study entitled ‘Impact of working life career and night work on life span. Male mortality risk in the 1924–1949 cohorts in Austria’. The study aims to identify the links between different factors of working life on the life span of workers and therefore on their expected time in retirement. The study focuses particular attention on the effects of heavy work carried out during night shifts on life expectancy.
The study is based on quantitative social security data from the Federation of Austrian Social Insurance Institutions (Hauptverband der österreichischen Sozialversicherungsträger) – obtained from anonymous individuals – for men born between 1924 and 1949. The advantage of the data base lies in the combination of information on different aspects of employment over the life course, including unemployment pension periods and day of death. Due to the particular focus on the effects of carrying out heavy work during night shifts, a special data selection was carried out for this specific group of workers.
Night work regulations
In Austria, since 1981, the Night Shift Workers (employment on arduous work) Act has been enacted to protect workers who face serious work strains and high health risks at work. According to this law, ‘heavy labour’ is defined as night work carried out between the hours of 22.00 and 06.00 combined with heavy workloads such as excessive heat and continuous loud noise. Employees who work for a longer period of time under these conditions are entitled to additional holidays, specific rest periods, extra severance pay, special preventive health and safety measures, and particular pension payments (Sonderruhegeld) at the age of 57 years. On the basis of this special pension payment, information relating to this group of workers could be easily extracted from the social security data.
Main findings of study
Life expectancy of workers
The study shows clear differences between blue-collar and white-collar workers in terms of life expectancy as a result of strenuous work (Figure 1 below). Whereas blue-collar workers have a probability of 75.7% of reaching the age of 70 years, the same holds true for 84.4% of white-collar workers. Surprisingly, blue-collar workers covered by the Night Shift Workers Act, which means that for a longer period of employment they are faced with serious work strains and high health risks, have the same probability of reaching the age of 70 years as white-collar workers (84.4%).
Figure 1: Probability of workers reaching age 70 years
Source: Austrian Institute for Economic Research (WIFO), 2008
Probability of workers reaching age 70 years
Income level matters
The multivariate analysis presented different reasons and factors for mortality and life span. First, income level is – as various studies show – a decisive factor for the life span of workers. The higher the average income level over the working life, the lower the mortality risk. Compared with those earning €7,000–€9,000 a year, workers with an income level of only €5,000 a year face a 50% higher mortality risk, while people earning more than €17,000 a year lower their mortality risk by 50%.
Unemployment as a risk factor
Unemployment also plays an important role regarding the life span of workers. According to the study, longer periods of unemployment are related to a higher mortality risk. One additional month in unemployment a year raises the mortality risk by 5.2% compared with continuous employment. This correlation is not affected by income level, as unemployment periods are associated with a lower income.
Impact of heavy work on life span
One of the most unexpected results of the study is that heavy work carried out during night shifts is not a risk factor for life span. The multivariate analysis presented possible reasons for this unexpected result by taking into consideration the abovementioned factors. As workers doing physically heavy work receive a higher salary due to their workloads, this partly explains their lower mortality risk. This group also shows a higher degree of continuous employment and fewer unemployment periods than other groups of blue-collar workers.
According to the study, these two factors – greater salary and high degree of continuous employment – explain an important element of the lower mortality risk of this group, but do not explain all of the differences. Therefore, the study’s authors argue that a crucial factor in explaining the residual lower mortality risk is the positive effect of the special health and safety regulations for workers faced with strenuous work and high health risks defined in the Night Shift Workers Act. Workers who undertake heavy work and are not covered by the act, such as those in the construction industry, show a much higher risk of mortality.
Another explanatory factor for this result could be the effect of a form of self-selection of high-capacity and healthier persons into stable and well-paid jobs involving heavy work.
On the basis of a good data selection, the study shows very interesting results. On the one hand, it points out the decisive influence of income levels and unemployment periods for mortality risk and life span. On the other hand, the results suggest that working conditions do not necessarily have a strong impact on life span, particularly when looking at the lower mortality risk of workers covered by the Night Shift Workers Act. Although it appears to be true that the effects of different explanatory factors have to be taken into consideration, the positive results for this specific group show that health and safety measures – in other words an improvement in working conditions especially with regard to heavy work – do have a positive impact on life span.
Böheim, R., Knittler, K. and Mahringer, H., Impact of working life career and night work on life span. Male mortality risk in the 1924–1949 cohorts in Austria, Austrian Institute of Economic Research (WIFO), Monographs, March 2008.
Manfred Krenn, FORBA