Mortality from circulatory diseases, especially ischaemic heart disease in sea pilots and boatmen in Sweden 1951-84: a retrospective cohort study.

A cohort of 1455 sea pilots and boatmen employed after 1921 was established. Those identified and alive in 1951 (n = 1323) were linked to the Swedish cause of death register 1951-84. In 21 352 person-years 383 deaths were observed among sea pilots compared with 379.3 expected (SMR = 101;95% CI between 99 and 112) and in 12,127 person-years the observed number of deaths among boatmen was 136, expected 135.9 (SMR = 100) when Swedish men were used as a reference population. For ischaemic heart disease (IHD) (ICD-8: 410-414) the SMR was equal to 96 (obs = 131, exp = 137.2) for sea pilots and 91 (obs = 44, exp = 48.4) for boatmen. No trend over time or geographical differences could be observed. A healthy worker effect could not explain why there was no excess mortality from IHD.     

Mortality from circulatory diseases, especially ischaemic heart disease in sea pilots and boatmen in Sweden 1951-84: a retrospective cohort study

A cohort of 1455 sea pilots and boatmen employed after 1921 was established. Those identified and alive in 1951 (n = 1323) were linked to the Swedish cause of death register 1951-84. In 21 352 person-years 383 deaths were observed among sea pilots compared with 379.3 expected (SMR = 101;95% CI between 99 and 112) and in 12,127 person-years the observed number of deaths among boatmen was 136, expected 135.9 (SMR = 100) when Swedish men were used as a reference population. For ischaemic heart disease (IHD) (ICD-8: 410-414) the SMR was equal to 96 (obs = 131, exp = 137.2) for sea pilots and 91 (obs = 44, exp = 48.4) for boatmen. No trend over time or geographical differences could be observed. A healthy worker effect could not explain why there was no excess mortality from IHD.     

Mortality from diabetes mellitus, ischemic heart disease, and cerebrovascular disease among blacks in a higher income area

According to the 1980 census, blacks in Suffolk County on Long Island, NY, had a median family income of almost $20,000 versus $12,618 for blacks in the entire United States, or only 20 percent lower than that for whites in the county. Black-white ratios of age-specific death rates for 1979-83 in Suffolk County were elevated for all causes for men and women in age groups from 35-44 to 55-64 years (but not for those 75 years or older), for ischemic heart disease for women (but not men) for age groups from 35-44 to 55-64 years, for diabetes mellitus for most ages (especially for females), and for cerebrovascular disease for both men and women for all age groups from 35-44 to 65-74 years. The age-specific proportional mortality ratios (PMRs) for ischemic heart disease within educational level (less than 12 years and 12 or more years of school) were lower for black than for white men but more similar for black and white women. For diabetes, the PMRs were higher for black versus white women within both educational levels. PMRs for cerebrovascular disease were higher for black than white men within the group of decedents with less than 12 years of education. The findings are discussed with reference to racial differences in the prevalence of poverty as well as possible differences in risk factors (for example, obesity) or medical care independent of poverty.     

Mortality from coronary heart disease and stroke for six ethnic groups in California, 1985 to 1990

Coronary heart disease and stroke death rates were compared for six ethnic groups (non-Hispanic white, Hispanic, African-American, Chinese, Japanese, and Asian Indian) by sex and age (25 to 44, 45 to 64, 65 to 84, and 25 to 84 years old) using California census and 1985 to 1990 death data. African-American men and women in all age groups had the highest rates of death from coronary heart disease, stroke, and all causes (except for coronary heart disease in the oldest men). Hispanics, Chinese, and Japanese in all age-sex groups had comparatively low death rates for coronary heart disease and stroke, although stroke was proportionally an important cause of death for Chinese and Japanese groups. Coronary heart disease was an important cause of death for Asian Indians although death rates were generally not higher than those for other ethnic groups. Ethnic differences were most marked for women and younger age groups.     

Trends in ischemic heart disease mortality in Italy, 1968-78.

In Italy during the period 1968-78, female heart disease mortality decreased in all age groups up to age 79, with an average annual rate of decline in the 35-74 age-standardized rate of over 0.7 per cent. In males, age-specific death rates in some age groups were stable or increased moderately, but in middle-aged (50 to 59) males there was a consistent increase so that the rise in the 35-74 age standardized male death rate was approximately 1 per cent per year.     

Mortality among masons in Iceland.

An investigation was carried out to determine the cause of death among 450 masons in Iceland who had been exposed to hexavalent chromium, a trace element in cement. The cohort was defined as all men born between 1905 and 1945 who had, according to the Register of Masons and Stone-cutters, finished vocational training as masons. For deaths occurring between 1951 and 1982 information was obtained from the Statistical Bureau of Iceland. Expected death rates were calculated, based on the national rates for men in the corresponding age groups. The total number of deaths from all causes was less than expected for the whole study period (81 v 85.86) but, with a 20 year latent period, 58 deaths were found against 50.57 expected; with a 30 year latent period, 38 deaths were found against 27.82 expected, which may, to a large extent, be accounted for by an excess of deaths from lung cancer. Nine deaths from lung cancer were found in the cohort, eight with 20 and 30 year latent periods compared with expected rates of 2.87, 2.19, and 1.28 respectively. The results seem to indicate that the increased number of deaths from lung cancer among the masons has a causal relation to occupational exposure.     

Mortality from cancer and ischemic heart disease in Danish chimney sweeps: a five-year follow-up

A mortality study of 713 male chimney sweeps in Denmark was performed. The observed number of deaths in 1970-1975 was compared with the expected number, calculated from cohort, period, and cause-specific death rates for employed Danish males. A total of 38 deaths was observed compared with the 18.3 deaths expected (p less than 0.01). Cancer accounted for 12 deaths versus 5.3 expected (p less than 0.05), ischemic heart disease for 12 deaths versus 5.4 expected (p less than 0.05), and residual causes for 14 deaths versus 7.6 expected (p less than 0.05). The excess mortality was exclusively due to cancer and ischemic heart disease among chimney sweeps in the older age group (45-74 years), whereas a high mortality due to other causes was observed among the younger sweeps (15-44 years). It is concluded that heavy inhalation exposure to products from the combustion of fossil fuel leads to an increased individual risk of cancer and ischemic heart disease and substantially reduces the time until occurrence of these diseases.     

Changing mortality patterns for major cancers in Spain, 1951-1985

Mortality trends for main cancer sites in Spain from 1951-1985 are presented. Age-standardized mortality rates per 100,000 were computed using the direct method. The Spanish population of 1970 was used as the standard. Age-standardized mortality rates for total cancer showed a marked increase among men throughout the period of study. This can be attributed mainly to the increase in lung cancer mortality (from 8.63 person-years to 44.74 between 1951 and 1985), which was only partially balanced by a reduction in the stomach cancer mortality (from 36.18 to 18.31). Among women the increase in total cancer is lower overall. It occurred mainly during the 1950s and thereafter the trend has remained stable and even declined in recent years. Lung cancer mortality rates among women have remained fairly stable and stomach cancer followed the same pattern as for men. Breast cancer mortality increased constantly during the period (from 7.21 to 19.38) but it was not until 1978 that it became the leading cause of cancer mortality among women.     

Urban-rural inequalities in ischemic heart disease in Scotland, 1981-1999

OBJECTIVES: We sought to describe the pattern and magnitude of urban-rural variation in ischemic heart disease (IHD) in Scotland and to examine the associations among IHD health indicators, level of rurality, and degree of socioeconomic deprivation. METHODS: We used routine population and health data on the population aged 40-74 years between 1981 and 1999 and living in 826 small areas (average population=5600) in Scotland. Three IHD health indicators-mortality rates (deaths per 100,000 population), rates of continuous hospital stays (discharges per 100,000 population), and rates of mortality in the hospital or within 28 days of discharge (MH+) were analyzed with multilevel Poisson models. A 4-level rurality classification was used: urban areas, remote small towns, accessible rural areas, and remote rural areas. RESULTS: Rates of mortality, continuous hospital stays, and MH+ increased with area socioeconomic deprivation. After adjustment for population age, gender, and deprivation, the relative risk of IHD mortality in remote rural areas was similar to that of urban areas in 1981; the relative risk of a continuous hospital stay was significantly lower (relative risk [RR] = 0.70; 95% confidence interval [CI] = 0.64, 0.76) and the relative risk of MH+ was higher (RR=1.18; 95% CI=1.04, 1.35) in remote rural areas. Mortality and MH+ declined for all ruralities over time. However, MH+ remains highest in remote rural areas and remote towns. CONCLUSIONS: Low standardized ratios of IHD continuous hospital stays and mortality in remote rural areas mask health problems among rural populations. Although absolute and relative differences between urban and rural rates of MH+ have diminished, the relative risk of MH+ remains high in remote rural areas.     

Mortality from violent causes among the elderly population in Finland in 1951-1979

The changes in violence-related mortality rates among the population aged 65 years or older in Finland from 1951-1979 were studied with the help of the official mortality statistics. Factors underlying these changes were also examined. The most distinctive findings were, first, the increase in accident-related mortality rates of both males and females in the 1950s and, second, the sharp decrease of those rates with respect to women from 1960-1975 compared to the decrease for males during that same period. The changes in mortality for males were mainly due to changes in frequency of motor-vehicle fatalities, whereas the changes for females were mainly due to changes in mortality caused by accidental falls and limb fractures. Improvements in classification methods resulting in the decrease of unspecified causes of death were apparently the main cause of the recorded increase in violent mortality in the early 1950s. The incidence of traffic accidents has decreased in the latter half of the 1970s. Thus, the minor decrease in motor-vehicle accident mortality for men most evidently was due to a decreased incidence. The incidence of hip and limb fractures in women increased. Thus, it was not a lowered incidence but instead a decreased case-fatality rate which caused the decreased mortality in females. Early mobilization after hip operations and decreased dependence level among the elderly apparently resulted in the decreased fatality rates.     

Mortality from ischaemic heart disease and cerebrovascular disease in Greenland

Mortality 1968-83 from Ischaemic Heart Disease (IHD) and Cerebrovascular Disease (CD) was studied in native Greenlanders. Mortality from IHD was lower in Greenland than in Denmark for both males and females and especially low in Greenlandic settlements. IHD mortality decreased during the period. Mortality from CD was higher in Greenland than in Denmark with no certain time trend. Living conditions, of which a high intake of seafood may be a key factor, and/or a genetic predisposition seem to protect Greenlanders from IHD and to predispose them to CD.     

Mortality study of fertiliser manufacturers in Iceland.

A retrospective cohort study was carried out on workers in a fertiliser plant to assess the risk of stomach and lung cancer. The cohort comprised 603 subjects and their death rates were compared with those of the general male population in Iceland. The study period was 1954 to 1985. The results do not provide evidence of an excess of deaths from stomach or lung cancer. Total mortality was lower than expected and even lower when the analysis was restricted to those who had worked at the plant for more than one year. Shiftwork operators had the highest SMRs for all cancers, however, with a reverse dose response according to duration of employment, indicating that this might be due to factors unrelated to manufacture of fertilisers. As examples of these factors life style and social class may be implicated, as well as possible selection of weaker subjects to do this assumed easy work.     

Regional differences in mortality from ischemic heart disease

The geographical distribution of mortality from ischaemic heart disease in the Netherlands has changed dramatically since 1950. In 1950-1954 mortality was highest in high-income, urbanized areas, in 1980-1984 the reverse was true. This development resembles the one observed in the United States of America. The changes in geographical distribution cannot be attributed to differences in cause-of-death certification. The change in the association with income and the association between mortality and a number of ischaemic heart disease risk factors found in 1970-1974, suggest that at least part of the explanation is a change in the geographical distribution of risk factors.     

Mortality among farmers in Iceland

A retrospective cohort study was performed to determine the cause of death among 5923 farmers in Iceland. Information on deaths occurring between 1977 and 1985 was obtained through the Statistical Bureau of Iceland. The vital status could be ascertained for all subjects in the study. Expected death rates were calculated, based on the national rates for males in the corresponding age groups and calendar years. The number of deaths from all causes, malignant neoplasms, lung cancer, ischaemic heart disease, respiratory diseases and accidents was less than expected in the total cohort and in nearly all subcohorts. There was no statistically significant excess risk, however: SMR for skin cancer was 2.30, SMR for Hodgkin's disease was 1.71, for leukaemia SMR was 1.60, and for brain cancer SMR was 1.23 in the total cohort. The results are in agreement with those of most previous studies of farmers, but because of the short follow-up time, the excess risk found for deaths from skin and haematological malignancies did not reach statistical significance. Further follow-up is planned in the future.     

Mortality among masons in Iceland

An investigation was carried out to determine the cause of death among 450 masons in Iceland who had been exposed to hexavalent chromium, a trace element in cement. The cohort was defined as all men born between 1905 and 1945 who had, according to the Register of Masons and Stone-cutters, finished vocational training as masons. For deaths occurring between 1951 and 1982 information was obtained from the Statistical Bureau of Iceland. Expected death rates were calculated, based on the national rates for men in the corresponding age groups. The total number of deaths from all causes was less than expected for the whole study period (81 v 85.86) but, with a 20 year latent period, 58 deaths were found against 50.57 expected; with a 30 year latent period, 38 deaths were found against 27.82 expected, which may, to a large extent, be accounted for by an excess of deaths from lung cancer. Nine deaths from lung cancer were found in the cohort, eight with 20 and 30 year latent periods compared with expected rates of 2.87, 2.19, and 1.28 respectively. The results seem to indicate that the increased number of deaths from lung cancer among the masons has a causal relation to occupational exposure.     

Mortality of UK oil refinery and petroleum distribution workers, 1951-2003

BACKGROUND: The health of UK petroleum industry workers has been monitored for many years. AIM: To identify any long-term adverse health outcomes from occupational exposures in this industry. METHODS: The mortality (1951-2003) and cancer morbidity (1971-2003) experienced by cohorts of 28,555 oil refinery workers and 16,477 petroleum distribution workers has been investigated. Study subjects were all those males first employed in the period 1946-74 at one of eight UK oil refineries or 476 UK petroleum distribution centres; all subjects had a minimum of 12 months employment with some employment after 1 January 1951. Observed numbers of cause-specific deaths and site-specific cancer registrations were compared with expectations based on national mortality and cancer incidence rates. RESULTS: Standardized mortality ratios (SMRs) were significantly <100 for all causes both in oil refinery workers (Obs 11,156, SMR 89) and in petroleum distribution workers (Obs 7320, SMR 96). Significantly elevated SMRs were shown in oil refinery workers for cancer of the pleura (mesothelioma) (Obs 64, SMR 261) and melanoma (Obs 48, SMR 168). Significantly elevated SMRs were not found in petroleum distribution workers for any site of cancer. Significantly elevated standardized registration ratios (SRRs) were only shown in oil refinery workers and for cancer of the pleura (mesothelioma) (Obs 115, SMR 274), melanoma (Obs 85, SMR 129) and other skin cancer (Obs 983, SRR 117). CONCLUSIONS: The only findings that showed clear evidence of an occupational cancer hazard were those for mesothelioma in oil refinery workers.