This study examined general and cause-specific mortality for immigrants and the Canadian born population during the period of 1990-1992. The mortality data are from the Canadian Vital Statistics system, and the population counts are from the 1991 census of Canada. Although 19 separate immigrant groups are included in the study, a large part of the analysis is restricted to two broad categories of migrants: New Wave, and Old Wave. The former immigrants constitute for the most part (as of the early 1990s) relatively recent arrivals to this country (i. e., China, Other Asia, Africa, South-Central America/Caribbean/Mexico). Most of the New Wave immigrants are Visible Minorities (immigrant groups that fall under the official definition of "visible" in terms of racial characteristics). The Old Wave immigrants have a more established history of immigration to Canada (predominantly Europeans and Americans).

The research is grounded in a conceptual framework based on factors that pertain to the pre and post migration experiences of immigrants as well as demographic compositional differences between groups (age, sex, marital status). Among the former set of factors are conditions associated with the country of origin (culture and situations exposing the migrant to disease causing agents in the home country). In the host society, immigrants' conditional risk of death is partly determined by their socioeconomic status, their degree of attachment to their ethnic community and the extent of acculturation to the new society. There are also unmeasureable factors that may determine mortality risk, including health selectivity and genetic predispositions to disease. A number of hypotheses are specified based on the conceptual framework and tested against the available mortality and census data. The typical strategy of the study involves a comparison of migrant death rates to the death rates of the Canadian born population and to the corresponding rates of the home based countries of the immigrants.

The findings of this investigation are generally consistent with research based on the experience of other immigrant receiving nations: Australia, France, United Kingdom and the United States. In Canada and in these societies overall death rates for immigrants are typically lower than the host populations. There appears to be a gradient in the observed mortality risks with respect to causes of death, with the more recent immigrants tending to enjoy noticeably reduced relative risks of death for both general and cause specific mortality. This suggests there is a combination of effects associated with migration and health. Positive health selectivity of the immigrants, especially among the more recent arrivals, and other aspects of the migrants’ background culture as well as conditions associated with their acculturation and adaptation to the new environment appear to also contribute to their relative survival advantage.

Multivariate analyses provide further indirect support for the proposition that immigrants enjoy the benefits of positive health selectivity throughout their experience in the new land, though with increasing duration in the host country there is some loss of their health advantage. The multivariate results also lend indirect support for the idea that acculturation can in some cases have health enhancing effects on immigrants, while in others it either has no relevance on death risk, or it works in such a way as to erode the survival advantage of the immigrants. Thus it seems acculturation as a process can have both beneficial and health-eroding influences on the immigrants.

There are wide variations in crude death rates across immigrant groups. Some immigrant groups have unusually high, while others have exceptionally low, crude death rates. In the former category are the immigrants from the Irish Republic, the former USSR, Sweden, Other Scandinavia, and Hungary. CDRs for these groups range from a high of 39.97 per 1000 population (Republic of Ireland), to 20.36 (Hungary). The Canadian born crude death rate is 6.54 per 1000.

Some of the lowest crude rates are found among immigrants from China, Other Asia, Africa, South Central America/Caribbean/Mexico. Among the Old Wave immigrant groups (i.e., those from traditional sending areas), the Greeks, the Italians and the Portuguese share overall crude death rates between four and nine per thousand population.

Indirect standardization involves the application of a standard population’s age-cause-specific death rates to the age-specific population distribution of a study group. In the present application, the Canadian born population is used as the standard to derive group-specific standardized mortality ratios (SMR_S).

In general, immigrants enjoy lower standardized death rates in relation to the Canadian born population. As well, the migrant SMRs tend to be lower than the SMRs of their countries of origin. Thus, not only do immigrants in general enjoy a lower mortality level from total and cause-specific mortality as compared to the Canadian born, but they also share a more favourable situation in relation to their home countries.

The overall mortality advantage of immigrants in relation to their host population and their countries of origin is partly a function of selectivity. The health selectivity thesis of immigrant mortality says that immigrants have below average morality rates as compared to their host populations because they are selected for good health. Selection takes on two forms: healthy persons migrate; and official health screening ensures that only healthy individuals enter the host nation.

The New Wave immigrants have a noticeable advantage in heart disease mortality risk as compared to the Canadian born and the Old Wave immigrants. Among the Old Wave immigrants, the most advantaged are the Greeks. Generally speaking, the heart disease risk profile of the Old Wave immigrants appears to be intermediate between their New Wave counterparts and the Canadian born. This suggests there may be some assimilative process at work, accounting for this apparent differential in heart disease. Perhaps the more established groups have been assimilating the diet and life style of the Canadian born, and over time this is resulting in a convergent process in heart disease mortality.

In general, cancer mortality is lower among immigrants as compared to their home countries and the Canadian born population. However, immigrant males and females have unusually high death rates from stomach cancer. This situation is likely the result of dietary change, associated with the migration experience. The New Wave immigrants enjoy very low death rates from all types of cancer examined in this study.

External types of mortality include suicide, homicide, and accidents.

Immigrants may experience high rates of suicide because of the stresses associated with settlement in a new land. If immigration is a stressful experience, immigrant groups should have relatively high suicide rates. And the stresses should be more intense during the early years after relocation, when the demands of adjustment to a new environment are greatest. As it turns, it out, the more recent immigrants groups---the New Wave---have very low suicide death rates.

Among the Old Wave immigrants, Greeks, Italians, Portuguese, and immigrants from the United Kingdom, have reduced risks, while Hungarians, Polish, and USSR migrants, share relatively high death rates of self-destruction. There appears to be some association (though imperfect) of immigrant suicide rates with religion, as evidenced in the cases of Italians, Portuguese, and South Americans/Mexicans, all of whom share a Catholic religious background culture. (The Polish, who are a predominantly Catholic group, show above average suicide rates; and migrants from the United Kingdom, a predominantly Protestant group, have suicide rates below expectation.)

These results suggest that both religion and other elements of national culture may be important determinants of immigrant suicide.

Americans, Irish Republic, and former USSR migrants all share elevated chances of death from "other accidents and violence." Of the remaining nativity groups, significant coefficients are noted for the Portuguese, Other Asians, Africans, South Central American/Caribbean/Mexico, and "other countries" immigrants.

The study examined a number of hypotheses for the observed group differences in general and cause-specific mortality. A fairly consistent finding is that socioeconomic status (SES) is in most cases a significant factor of mortality in both the Canadian born and the immigrant populations.

It was hypothesized that differences in ethnic community cohesion would explain part of the variations in mortality risk. This thesis received some support. But the effect of ethic community seems more relevant among New Wave immigrants than among the Old Wave migrants. Thus, the "protective" effects of community seem more important for relatively new immigrant groups.

Another hypothesis was in connection with country of origin effects on immigrant mortality. It was surmised that there would be a correlation between the death rates of home country with the death rates of corresponding immigrants, This hypothesis gained partial support. Among Old Wave migrants the association is negative (i.e., the higher the death rate in the country of origin, the lower the immigrant death rate); and among New Wave, it is positive (i.e., the higher the death rate in the home country, the higher the death rate among immigrants).

The hypothesis of acculturation was also investigated. According to this thesis, acculturation to the host society would lead to convergence in death probabilities between immigrants and the Canadian born population. This hypothesis gained some support. However, acculturation in some cases raised the risk of death among immigrants, while in others it helped to reduce it.

In an overall sense the results of this exploratory investigation suggest the following profile of immigrant health and survival prospects in Canadian society.

First, the majority of newcomers to this land have been persons in the prime working ages, which in most cases represent the most productive and healthiest years of one’s life. A related feature of this is the corollary fact that immigrants self-select themselves out of their populations of origin with respect not only to age, but also with regard to occupational skills and training and also good mental and physical health. In general, individuals who make the decision to move to an immigrant receiving country will tend to be a healthy subset of their populations of origin. Sick people generally do not migrate. This is especially true in the case of long distance moves that involve the crossing of national boundaries.

Secondly, due to the highly regulated and restricted nature of international migration in the modern context, prospective immigrants are screened to ensure they do not carry into the new country any major health problem. Another side to this scenario, which is extremely difficult to verify, is the likely possibility that the less adaptive and less healthy elements of the immigrant population in Canada will select themselves out of the country and return to their countries of origin. To the extent that this return migration process represents a real aspect of the migration experience of immigrants in Canada, it would certainly have the effect of further enhancing the positive health selectivity of those migrants who remain in the host society.

Thirdly, the more advantaged survival profile of immigrants may also arise from their access to Canada's exceptional array of health services. This fact alone would account for a gain in health status among newcomers, who for the most part consist of people from areas of the world in which health care accessibility is nowhere near that provided by Canada. All other things being equal, greater access to good health care should translate into gains in the health status among immigrants.

Fourthly, notwithstanding health selectivity and access to a superior health system, it is also likely that with increased duration of stay in the adopted society, the greater the degree to which the health advantage of the immigrants reduces towards the general average of the host population. This may be thought of as a being a generalized phenomenon of regression to the average level of health in a society. The causal mechanisms for this regressive tendency in terms of overall health involve the tendency of immigrants to gradually acculturate the life styles, habits and orientations of the host society. To this one may also add the cumulative effects on health of life stresses on the organism as one gets increasingly older.

Fifthly, most immigrants (especially among the first generation) maintain close ties to their ethnic communities in the New World. This affords newcomers and more established immigrants an indispensable source of informal and formal support, thus minimizing the health eroding effects of rapid change associated with immigration to a new environment. One way in which the support of the ethnic community affects health if through its social integrative and social control functions in reducing the risk of certain types of mortality, including suicide, homicide, and other forms of violence.

A sixth factor underlying the survival advantage of immigrants may be associated with their socioeconomic experience. Some of the Canadian based literature on immigrants suggests that for most foreign born people in this country socioeconomic hardship is of a transitory nature. Economic difficulties, if they arise, tend to occur in the early phases of settlement. While many newcomers go through an adjustment phase and perhaps even experience poverty, over the long term the majority of immigrants in Canada do reasonably well economically and are able to extricate themselves out of poverty or economic deprivation. This means that in most cases the negative consequences of economic hardships on health are likely temporary.

Finally, it is important to point out that due to heterogeneity in genetic and biological factors among immigrant populations, the health and mortality profiles of immigrants cannot be assumed to be uniform. Some immigrant groups will do better than others in terms of health as a result of inherent genetic differences in predisposition to serious diseases (e.g. sickle cell anemia). Even within any given population, there are countless unmeasurable differences in frailty, again related to constitutional differences among persons (i.e. some people are more advantaged in genetic make up and will therefore live longer than others). As well, immigrant populations are culturally diverse entities. As such, any observed health and mortality differentials across groups may be partly linked to variations in diet, nutrition, health habits, and psychological orientations, all of which are partly if not wholly conditioned by culture. Culture can either confer advantages or disadvantages in terms of health to the extent that it promotes or fails to promote healthy ways of living.

A word of caution is necessary when interpreting the results of this investigation. The data used in the analysis of immigrant mortality cannot be assumed to be devoid of errors. Despite any methodological and data issues, however, the present study offers insight into one aspect of the immigrant experience in Canada. It provides insight into the mortality and survival patterns of the immigrant population, an area of research that has been generally neglected in Canada.