Cardiovascular disease mortality in British merchant shipping and among British seafarers ashore in Britain

Abstract

Background: The objective was to investigate trends in work-related mortality from cardiovascular disease (CVD) among seafarers employed in British merchant shipping from 1919 to 2005, to compare CVD mortality among British seafarers at work in British shipping - and ashore in Britain - with that in the general British population, and to investigate work-related CVD mortality in British shipping during recent years according to factors such as rank, nationality, location, and type of ship.

Material and methods: A longitudinal study based on examination of death inquiry files and death registers, official death returns, and information from occupational mortality decennial supplements. The main outcome measures were population-based mortality rates and standardised mortality ratios.

Results: There was an increase in work-related CVD mortality throughout much of the period from 1919 to 1962, but a subsequent reduction to 2005. Work-related mortality from CVD and ischaemic heart disease (IHD) was lower among seafarers employed in British shipping than in the corresponding general population (SMRs = 0.35 to 0.46), but mortality from CVD among British seafarers ashore in Britain was often increased. An elevated risk of work-related CVD mortality was also identified among the crews of North Sea offshore ships.

Conclusions: This study shows a healthy worker effect against CVD mortality among seafarers at work in British shipping, but increased risks among British seafarers ashore in Britain, which would include seafarers discharged through CVD morbidity and other illnesses. The high risks of CVD mortality among seafarers in North Sea supply ships may reflect particular work-related hazards in this sector.