Convergence of male and female lung cancer mortality at younger ages in the European Union and Russia

Background: Lung cancer epidemics emerged first among males in European countries in the first half of the 20th century and then among females in the second half. We have explored the recent convergence in sex ratios. Methods: Age-standardized (world standard) lung cancer mortality rates at ages 20 to 44 years were derived from WHO for 26 countries separately from the beginning of their data series to 2002. The most recent periods in which trends could be adequately represented as linear were determined using the software package 'Joinpoint'. Countries were classified by their statistically significant trends for each sex in these periods. Results: Lung cancer mortality among young adult males tended to decrease. Among females there were significant recent increases in eight (Pattern 1) countries and no significant trend in 16 (Pattern 2) countries. Rates decreased in both sexes in the UK and rose in both sexes in Portugal. The extent to which sex ratios had actually converged by 2002 varied widely, with values still above 3 in six eastern countries and below 1 in Scandinavia, the Netherlands and Ireland. Conclusion: At the beginning of 21st century, there is a general tendency for sex ratios for lung cancer mortality to converge towards 1, but with considerable variation in the extent to which such convergence has been realized.