Mortality inequalities by occupational class among men in Japan, South Korea and eight European countries: A national register-based study, 1990-2015

Background We compared mortality inequalities by occupational class in Japan and South Korea with those in European countries, in order to determine whether patterns are similar. Methods National register-based data from Japan, South Korea and eight European countries (Finland, Denmark, England/Wales, France, Switzerland, Italy (Turin), Estonia, Lithuania) covering the period between 1990 and 2015 were collected and harmonised. We calculated age-standardised all-cause and cause-specific mortality among men aged 35-64 by occupational class and measured the magnitude of inequality with rate differences, rate ratios and the average inter-group difference. Results Clear gradients in mortality were found in all European countries throughout the study period: manual workers had 1.6-2.5 times higher mortality than upper non-manual workers. However, in the most recent time-period, upper non-manual workers had higher mortality than manual workers in Japan and South Korea. This pattern emerged as a result of a rise in mortality among the upper non-manual group in Japan during the late 1990s, and in South Korea during the late 2000s, due to rising mortality from cancer and external causes (including suicide), in addition to strong mortality declines among lower non-manual and manual workers. Conclusion Patterns of mortality by occupational class are remarkably different between European countries and Japan and South Korea. The recently observed patterns in the latter two countries may be related to a larger impact on the higher occupational classes of the economic crisis of the late 1990s and the late 2000s, respectively, and show that a high socioeconomic position does not guarantee better health.