Henrik Lyngbeck Hansen

Hospitalisations among seafarers on merchant ships

Aims: To study morbidity among active seafarers in the merchant navy in order to clarify possible work related morbidity and the morbidity related to work and lifestyle where possible preventive measures may be initiated. Methods: From a register in the Danish Maritime Authority a cohort of Danish merchant seafarers who had been actively employed at sea in 1995 was identified. For each seafarer, information on all employment periods at sea, charge aboard, and ship was available. The cohort was linked with the National In-patient Register in Denmark. Standardised hospitalisation ratios (SHRs) were calculated for all major diagnostic groups using all gainfully employed as reference. Results: Seafarers were shown to be inhomogeneous, with significant differences in SHRs for the same disease groups between different groups of seafarers depending on charge and ship type. SHRs for lifestyle related diseases were high, although rates for acute conditions, such as acute myocardial infarction, were low, probably due to referral bias, as acute conditions are likely to cause hospitalisation abroad, and thus are not included in the study. SHRs for injury and poisoning were high, especially for ratings and officers aboard small ships. Conclusion: Despite pre-employment selection, a large proportion of the seafarers constitute a group of workers with evidence of poor health probably caused by lifestyle. The subgroups with high risk of hospitalisation due to lifestyle related diseases also had an increased risk of hospitalisation due to injury and poisoning.

Female seafarers adopt the high risk lifestyle of male seafarers

OBJECTIVE: To study the mortality of women in an occupation known to have a high mortality among men. METHODS: A total of 6788 female seafarers of all job categories who had been employed on Danish merchant ships, passenger ships, and privately owned ferries between 1986 and 1993, were followed up until the end of 1993. RESULTS: Standardised mortality ratio (SMR) was 1.20 (95% confidence interval (95% CI) 0.89 to 1.58) for all causes of death and job categories together. For women in traditionally male jobs, SMR was 2.82 (1.41-5.05), whereas galley and catering staff had SMRs close to the general female population. The high mortality among women in traditional male jobs could be explained by a high risk of fatal accidents including occupational accidents. In the whole cohort, there were fewer deaths from natural causes than expected but an excess risk of death due to lung cancer, heart diseases, and non-natural deaths. CONCLUSION: The increased mortality could primarily be explained by an excess risk of fatal accidents and suicide. Especially, female seafarers entering traditional male jobs had a high risk of fatal accidents, not only at sea but also ashore. An excess risk of dying of lung cancer and heart diseases probably reflects a high tobacco consumption. Female seafarers are probably influenced by their occupation towards hazardous behaviour and a high risk lifestyle but people with a high risk lifestyle may also be attracted by or forced into high risk jobs such as traditional male jobs at sea.

Health of Danish seafarers and fishermen 1970-2010: What have register-based studies found?

Background:This study aimed to review Danish register-studies on seafarers’ and fishermen’s health and safety. Methods: Register-based or register-linked studies from 1970 until 2012 were identified and reviewed. Four categories of studies were included: mortality, hospitalization, specific diagnoses and conditions and accidents. Standardized risks estimates were typically calculated by comparison with the total Danish working population. Results: Elevated rates were found in all four categories. For mortality male seafarers had excess rates of accidents, cirrhosis of the liver, cancer, and suicides, and fishermen of accidents and cardiovascular disorders. Female seafarers in male-dominated occupations also had increased mortality rates. Elevated hospitalization rates for male seafarers were particularly prominent for endocrine/nutritional conditions, cervical discopathy, gastrointestinal and cardiovascular diseases, cancers, hearing impairment, and injuries, and for female seafarers cancers, circulatory and genitourinary diseases and injuries. Fishermen had increased hospitalization rates for cardiovascular diseases, bronchitis, emphysema, lung cancer, gonarthrosis, thoracolumbar discopathy, rotator cuff syndrome, carpal tunnel syndrome, injuries and hearing impairment. Specific diagnoses and conditions: There was an elevated risk of tuberculosis, hepatitis B and certain cancers for male seafarers, and of obesity and occupational accidents for both fishermen and seafarers. Conclusions: In spite of safety measures and significant structural changes in the Danish merchant and fishing fleet, the spectrum of health indicators continues to indicate considerable risk factors in the maritime environment and/or the lifestyle of seafarers and fishermen. Future monitoring of fishermen’s and seafarers’ health will remain essential for implementing appropriate preventive measures.

Cancer incidence among merchant seafarers: an extended follow-up of a Danish cohort

Objectives While maritime safety generally has improved dramatically over the last century, modern seafarers are still faced with numerous occupational hazards potentially affecting their risk of chronic diseases such as cancer. The aim of this study is to offer updated information on the incidence of specific cancers among both male and female seafarers. Methods Using records from the Danish Seafarer Registry, all seafarers employed on Danish ships during 1986–1999 were identified, resulting in a cohort of 33 084 men and 11 209 women. Information on vital status and cancer was linked to each member of the cohort from the Danish Civil Registration System and the Danish Cancer Registry using the unique Danish personal identification number. SIRs were estimated for specific cancers using national rates. Results The overall incidence of cancer was increased for both male and female seafarers (SIR 1.19, 95% CI 1.15 to 1.23, and SIR 1.14, 95% CI 1.07 to 1.22) compared with the general population. This excess was primarily driven by increases in gastrointestinal, respiratory and genitourinary cancers. In addition, male seafarers working in areas with asbestos exposure showed significantly increased risk of mesothelioma. Finally, the male seafarers had an increased risk of lip cancer. Conclusions The majority of cancers among seafarers continue to be lifestyle-related. However, occupational exposure to asbestos and ultraviolet radiation seems to affect the cancer pattern among the male seafarers as well.