Ethnic Differences in the Prevalenc...

Ethnic Differences in the Prevalence of Pulmonary Airflow Obstruction Among Grain Workers

Data compiled at the World Health Organization (WHO) in 1971 indicated an approximate five-fold difference in mortality rates from bronchitis, emphysema, and asthma combined, among males aged 45 and above in various European populations. [1] Although these data are make liable to variation in diagnostic and coding practices and get to from countries with different tobacco consumption rates, they may also meditate biologic differences in risk of obstructive lung disease in different European populations. If for a like reason ethnic origin might be a significant factor to consider in predicting risk of obstructive airways disease.

In the WHO European data, the British and Romanians had the highest reported mortality rates, five times that of the Swedes, Norwegians, and French who were among the lowest. That earnestly of this elevated risk in the British might be appropriate to environmental factors is supported through work of Reid [2] who showed that British-born immigrants to the United States had mortality rates from chronic lung disease similar to the rates for individuals born and residing permanently in the states, if it were not that only about one-fifth the rate for Britons residing in the United Kingdom. Other factors thinking to be associated with the high

prevalence of obstructive airways disease among the British are increasing urbanization, [3-5] air pollution and/or mist [6-8] dust exposure, [9] tobacco consumption, [10-12] and grave socioeconomic status. [11,12]

Nevertheless, obstructive airways disease fittings the criteria for multifactorial disease with the two genetic and environmental factors making demonstrable contributions to risk. n12 The possibility therefore exists that a of the differences in prevalence between ethnic clusters may be due to their varying genetic makeup. To criterion the significance of ethnicity in the growth of obstructive airways disease in populations in their abiding-place environment would be a difficult task because of the many differences in confounding variables of that kind as smoking habits, climate, differing occupational fronts different diagnostic, reporting procedures, etc yet such an analysis could be carried abroad in a group of immigrants of varying ethnic backgrounds who now have similar environmental in all sensess Such an opportunity was currented to us by data gathered in a surveillance program undertaken with the men who work in the Saskatchewan fatherland grain elevators.

Saskatchewan was settl during the first decades of the 20th hundred years by groups of immigrants who came largely from the northern European countries. Each national form into groups tended to establish its avow set of communities. These communities retained long of the groups' Old World cultural traditions, serv as the center for social activities, and were the source of marriage partners for the recent generation. Consequently, many native-born Saskatchewanians trace their ancestry, within united or two generations, to a single area of Europe eg the British Isles, Scandinavia, etc As a be the effect many Saskatchewan residents may be classified as British, Scandinavian, etc because all four of their grandparents were born in that area of Europe

An inland province with a population of single in kind million, occupying approximately 600,000 sq km Saskatchewan has little air pollution and a relatively uniform climate quite through the province with little haze moderate summer temperatures, and prolonged cold (to -40[degrees]C), dry winters. A network of rail lines servicing small nation grain elevators covers the southern, arable portion of the province. These elevators, each of which enlist in one's services one to three men, help as temporary storage sites to which farmers deliver their grain, prior to its further transport through rail. Movement of grain within the elevator generates high dust flats and until approximately 12 years ago when the installation of effective dust removal equipment was begun, the working environment had high (up to 890 [mg/msup3]) flushs of grain dust. [13] The men who worked in these elevators had an increased risk of developing airflow obstruction. [14]

The grain elevator(s) is the greatest in number prominent feature in most Saskatchewan towns, and the grain workers engageed there occupy a unique position in the community because of their stable salary and their part as buyer of farmers' grain. Because of their position in the community, grain workers quite through the province have similar socioeconomic status. Thus, men who work in the Saskatchewan grain elevators give an account of a high risk group with similar environmental prospects and similar socioeconomic status in which differences in susceptibility to airflow obstruction in different ethnic or national disposes might be detected.

MATERIALS AND METHODS

Subjects

From 1973-1975 a measure and estimate was conducted of men exerciseed by the Saskatchewan country grain elevators. Data were obtained from 1395 men comprising 98 percent of employee of the largest grain elevator company plus 300 men who had been intrust with an agencyed for more than five years by means of the other elevator companies. Chest roentgenograms, spirometric criterions questionnaires, and blood samples were obtained from all participants. [15]