Differences in all-cause mortality: A comparison between immigrants and the host population in Norway 1990-2012

Subsequent fracture risk in Norwegians and immigrants with an index forearm fracture: a cohort study

The current study investigated subsequent fracture risk following a forearm fracture in three country of birth categories: Norway, Europe and North America, and other countries. Subsequent fracture risk was modestly higher in Norwegian-born individuals compared to the two other groups. Secondary fracture prevention should be recommended regardless of country background.

BACKGROUND

Fracture risk is higher in patients with a previous fracture, but whether subsequent fracture risk differs by origin of birth is unknown. This study explores subsequent fracture risk in patients with an index forearm fracture according to region of birth.

METHODS

Nationwide data on forearm fractures in patients ≥ 18 years in 2008-2019 were obtained from the Norwegian Patient Registry and Statistics Norway. Index fractures were identified by ICD-10 code S52, whereas subsequent fractures included any ICD-10 fracture code. Data on country of birth were from Statistics Norway and included three regional categories: (1) Norway, (2) other Europe and North America and (3) other countries. Direct age standardization and Cox proportional hazard regression were used to analyse the data.

RESULTS

Among 143,476 individuals with an index forearm fracture, 35,361 sustained a subsequent fracture. Norwegian-born forearm fracture patients had the highest subsequent fracture rates (516/10,000 person-years in women and 380 in men). People born outside Europe and North America had the lowest rates (278/10,000 person-years in women and 286 in men). Compared to Norwegian-born individuals, the hazard ratios (HRs) of subsequent fracture in individuals from Europe and North American were 0.93 (95% CI 0.88-0.98) in women and 0.85 (95% CI 0.79-0.92) in men. The corresponding HRs in individuals from other countries were 0.76 (95% CI 0.70-0.84) in women and 0.82 (95% CI 0.74-0.92) in men.

CONCLUSION

Individuals born outside Norway had a lower subsequent fracture risk than Norwegian-born individuals; however, subsequent fracture risk increased with age in all groups. Our results indicate that secondary fracture prevention should be recommended regardless of region of origin.

Mental health and risk of death and hospitalization in COVID-19 patients. Results from a large-scale population-based study in Spain

The COVID-19 pandemic has created unprecedented challenges for health care systems globally. This study aimed to explore the presence of mental illness in a Spanish cohort of COVID-19-infected population and to evaluate the association between the presence of specific mental health conditions and the risk of death and hospitalization. This is a retrospective cohort study including all individuals with confirmed infection by SARS-CoV-2 from the PRECOVID (Prediction in COVID-19) Study (Aragon, Spain). Mental health illness was defined as the presence of schizophrenia and other psychotic disorders, anxiety, cognitive disorders, depression and mood disorders, substance abuse, and personality and eating disorders. Multivariable logistic regression models were used to examine the likelihood of 30-day all-cause mortality and COVID-19 related hospitalization based on baseline demographic and clinical variables, including the presence of specific mental conditions, by gender. We included 144,957 individuals with confirmed COVID-19 from the PRECOVID Study (Aragon, Spain). The most frequent diagnosis in this cohort was anxiety. However, some differences were observed by sex: substance abuse, personality disorders and schizophrenia were more frequently diagnosed in men, while eating disorders, depression and mood, anxiety and cognitive disorders were more common among women. The presence of mental illness, specifically schizophrenia spectrum and cognitive disorders in men, and depression and mood disorders, substance abuse, anxiety and cognitive and personality disorders in women, increased the risk of mortality or hospitalization after COVID-19, in addition to other well-known risk factors such as age, morbidity and treatment burden. Identifying vulnerable patient profiles at risk of serious outcomes after COVID-19 based on their mental health status will be crucial to improve their access to the healthcare system and the establishment of public health prevention measures for future outbreaks.

Comparing the cognitive functioning of middle-aged and older foreign-origin population in Estonia to host and origin populations

Background

In migration and health research, the healthy migrant effect has been a common finding, but it usually pertains to specific contexts only. Existing findings are inconsistent and inconclusive regarding the cognitive functioning of the (aging) foreign-origin population relative to the populations of their host and sending countries. Moreover, this comparison is an understudied design setting.

Objective

We analyze the outcomes and associations of cognitive functioning outcomes of the non-institutionalized middle-aged and older population, comparing the Russian-origin population in Estonia with Estonians in Estonia and Russians in Russia in a cross-sectional design. We aim to estimate the (long-term) effects of migration on cognitive functioning in later life, contextualizing the findings in previous research on the healthy migrant effect.

Data and methods

We use data from face-to-face interviews conducted within the SHARE Estonia (2010-2011) and SAGE Russia (2007-2010) surveys. Respondents aged 50+ living in urban areas were grouped by self-identified ethnicity, including 2,365 Estonians, 1,373 Russians in Estonia, and 2,339 Russians in Russia (total N = 6,077). Cognitive functioning was measured using a 25-percentile cut-off threshold for the results of two cognition outcomes - immediate recall and verbal fluency - and the odds of impairment were estimated using binary logistic regression.

Results

Russian men and women living in Estonia have significantly higher odds of impairment in immediate recall than Estonian men and women, though they do not differ from Russians in Russia in the final adjusted models. The differences between all groups are non-significant if age at migration is considered. There are no significant differences between the groups in verbal fluency.

Conclusion

Contrary to the commonly found healthy migrant effect, the middle-aged and older foreign-origin population in Estonia fares initially worse than the native population in the immediate recall outcome, but does not differ from their sending country population, possibly due to Russia's higher mortality rate and therefore the selective survival of healthier people. Different results depending on the cognitive functioning outcome suggest that migration may affect temporary memory more than crystallized knowledge. However, there are no differences between the groups if defined based on age at migration, which suggests that the age profile differences explain most of the groups' differences in cognitive functioning.

Multimorbidity, social determinants and intersectionality in chronic patients. Results from the EpiChron Cohort

Background

Multimorbidity is influenced in an interconnected way, both in extent and nature, by the social determinants of health. We aimed at implementing an intersectional approach to analyse the association of multimorbidity with five important axes of social inequality (i.e. gender, age, ethnicity, residence area and socioeconomic class).

Methods

We conducted a cross-sectional observational study of all individuals who presented with at least one chronic disease in 2019 (n = 1 086 948) from the EpiChron Cohort (Aragon, Spain). Applying intersectional analysis, the age-adjusted likelihood of multimorbidity was investigated across 36 intersectional strata defined by gender, ethnicity, residence area and socioeconomic class. We calculated odds ratios (OR) 95% confidence interval (CI) using high-income urban non-migrant men as the reference category. The area under the receiver operator characteristics curve (AUC) was calculated to evaluate the discriminatory accuracy of multimorbidity.

Results

The prevalence of multimorbidity increased with age, female gender and low income. Young and middle-aged low-income individuals showed rates of multimorbidity equivalent to those of high-income people aged about 20 years older. The intersectional analysis showed that low-income migrant women living in urban areas for >15 years were particularly disadvantaged in terms of multimorbidity risk OR = 3.16 (95% CI = 2.79-3.57). Being a migrant was a protective factor for multimorbidity, and newly arrived migrants had lower multimorbidity rates than those with >15 years of stay in Aragon, and even non-migrants. Living in rural vs. urban areas was slightly protective against multimorbidity. All models had a large discriminatory accuracy (AUC = 0.7884-0.7895); the largest AUC was obtained for the model including all intersectional strata.

Conclusions

Our intersectional approach uncovered the large differences in the prevalence of multimorbidity that arise due to the synergies between the different socioeconomic and demographic exposures, beyond their expected additive effects.

Changes in life expectancy and disease burden in Norway, 1990–2019: an analysis of the Global Burden of Disease Study 2019

Background

Methods

Findings

Interpretation

Funding

Immigration, mortality, and national life expectancy in the Nordic region, 1990–2019

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Immigrants have higher life expectancy at age 1 than the native-born in Denmark, Finland and Norway do from 1990 to 2019.

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Immigrants in Denmark, Finland and Norway increasingly enhance national life expectancy at age 1 over time.

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Immigrants in Sweden have lower life expectancy at age 1 than native-born in Sweden do in 1990, but similar levels by 2019.

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The effect of immigrants on national life expectancy at age 1 in Sweden transforms from negative to positive over time.

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The unique mortality of immigrants affects rankings of life expectancy at age 1 in the Nordic region in recent years.

The influence of metabolic factors and ethnicity on breast cancer risk, treatment and survival: The Oslo ethnic breast cancer study

BACKGROUND

Breast cancer risk remains higher in high-income compared with low-income countries. However, it is unclear to what degree metabolic factors influence breast cancer development in women 30 years after immigration from low- to a high-incidence country.

METHODS

Using Cox regression models, we studied the association between pre-diagnostic metabolic factors and breast cancer development, and whether this association varied by ethnicity among 13,802 women participating in the population-based Oslo Ethnic Breast Cancer Study. Ethnic background was assessed and pre-diagnostic metabolic factors (body mass index, waist:hip ratio, serum lipids and blood pressure) were measured. A total of 557 women developed invasive breast cancer, and these women were followed for an additional 7.7 years.

RESULTS

Among women with an unfavorable metabolic profile, women from south Asia, compared with western European women, had a 2.3 times higher breast cancer risk (HR 2.30, 95% CI 1.18-4.49). Compared with the western European women, the ethnic minority women were more likely to present with triple-negative breast cancer (TNBC) (OR 2.11, 95% CI 0.97-4.61), and less likely to complete all courses of planned taxane treatment (OR 0.26, 95% CI 0.08-0.82). Among TNBC women, above-median triglycerides:HDL-cholesterol (>0.73) levels, compared with below-median triglycerides:HDL-cholesterol (≤0.73) levels, was associated with 2.9 times higher overall mortality (HR 2.88, 95% CI 1.02-8.11).

CONCLUSIONS

Our results support the importance of metabolic factors when balancing breast cancer prevention and disease management among all women, and in particular among non-western women migrating from a breast cancer low-incidence to a high-incidence country.

Spousal order of migration, gender, and hospitalization among immigrants in Denmark

Background: Certain migration contexts that may help clarify immigrants' health needs are understudied, including the order in which married individuals migrate. Research shows that men, who are healthier than women across most populations, often migrate to a host country before women. Using Danish register data, we investigate descriptive patterns in the order that married men and women arrive in Denmark, as well as whether migration order is related to overnight hospitalizations. Methods: The study base includes married immigrants who lived in Denmark between January 1, 1980 and December 31, 2014 (N = 13,680). We use event history models to examine the influence of spousal migration order on hospitalizations. Results: The order that married individuals arrive in Denmark is indeed highly gendered, with men tending to arrive first, and varies by country of origin. Risk of hospitalization after age 50 does not depend on whether an individual migrated before, after, or at the same time as their spouse among either men or women. However, among those aged 18+, men migrating before their wives are more likely to experience hospitalizations within the first 5 years of arrival. Conclusions: These findings provide the first key insights about gendered migration patterns in Denmark. Although spousal order of migration is not related to overnight hospitalization among women, our findings provide preliminary evidence that men age 18+ who are first to arrive experience more hospitalization events in the following 5 years. Future research should explore additional outcomes and whether other gendered migration contexts are related to immigrants' health.

Mortality differences between migrants and Italians residing in Rome before, during, and in the aftermath of the great recession. A longitudinal cohort study from 2001 to 2015

Background

In Europe, one of the most consistent findings is that of migrant mortality advantage in high-income countries. Furthermore, the literature shows that economic shocks, which bring worse health outcomes, can severely affect the most disadvantaged individuals. We analyse differences and changes in all-cause mortality between Italians and migrants residing in Rome before, during, and in the aftermath of the Great Recession (2001–2015) by birth-cohort.

Methods

The analysis is a longitudinal open cohort study. Mortality data come from the Register of the Causes of Death (58,637 deaths) and the population denominator (n = 2,454,410) comes from the Municipal Register of Rome. By comparing three time-periods (2001–2005, 2006–2010, and 2011–2015), we analyse all-cause mortality of Rome residents born, respectively, in the intervals 1937–1976, 1942–1981, 1947–1986 (aged 25–64 years at entry into observation). Computing birth-cohort-specific death rates and applying parametric survival models with age as the time-scale, we compare mortality differences between migrants and Italians by gender, area of origin, and time-period.

Results

Overall, we find a lower risk of dying for migrants than Italians regardless of gender (Women: HR = 0.61, 95% CI 0.56–0.66; Men: HR = 0.49, 95% CI 0.45–0.53), and a lower death risk over time for the total population. Nevertheless, such a pattern changes according to gender and migrants’ area of origin.

Conclusion

Given the relevance of international migrations in Europe, studying migrants’ health has proved increasingly important. The deterioration in migrant health and the gradual weakening of migrants’ mortality advantage is likely to become a public health issue with important consequences for the healthcare system of all European countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12176-8.

A Global Meta-analysis of the Immigrant Mortality Advantage

A large body of research on the “Healthy Immigrant Effect” (or “Paradox”) has reported an immigrant mortality advantage. However, other studies do not find such significant effects, and some even present contradictory evidence. This article is the first systematic meta-analysis that investigates the immigration-mortality relationship from a global perspective, examining 1,933 all-cause and cardiovascular mortality risk estimates from 103 publications. Our comprehensive analysis allows us to assess interactions between origin and destination regions and to reexamine, on a global scale, some of the most notable explanations for the immigrant mortality advantage, including suggestions that this paradox may be primarily the result of selection effects. We find evidence for the existence of a mild immigrant mortality advantage for working-age individuals. However, the relationship holds only for immigrants who moved between certain world regions, particularly those who immigrated from Northern Africa, Asia, and Southern Europe to richer countries. The results highlight the need in the broader migration literature for an increased focus on selection effects and on outcomes for people who chose not to migrate or who were denied entry into their planned destination country.

Age variations and population over-coverage: Is low mortality among migrants merely a data artefact?

The migrant mortality advantage has been observed extensively, but its authenticity is debated. In particular, concerns persist that the advantage is an artefact of the data, generated by the problems of recording mobility among foreign-born populations. Here, we build on the intersection of two recent developments: the first showing substantial age variation in the advantage-a deep U-shaped advantage at peak migration ages-and the second showing high levels of population over-coverage, the principal source of data artefact, at the same ages. We use event history analysis of Sweden's population registers (2010-15) to test whether this over-coverage can explain age variation in the migrant mortality advantage. We document its U-shape in Sweden and, crucially, demonstrate that large mortality differentials persist after adjusting for estimated over-coverage. Our findings contribute to ongoing debate by demonstrating that the migrant mortality advantage is real and by ruling out one of its primary mechanisms.

Ethnic differences in risk of hip fracture in Norway: a NOREPOS study

Hip fracture is a major public health problem, and the incidence rates vary considerably between countries. Ethnic differences in bone mineral density have been identified as a factor to explain some of the geographical differences in rates of hip fracture. In this Norwegian register-based study, we found that all immigrant groups experienced lower risk of hip fracture than individuals born in Norway.

INTRODUCTION

Norway is among the countries with the highest incidence rates. The aim of this study was to investigate differences in risk of hip fracture between ethnic groups living in Norway.

METHODS

We linked individuals in the Norwegian Population and Housing Census conducted in 2001 and a database consisting of all hip fractures in Norway in the period 2001-2013. Residents (n = 1,392,949) between 50 and 89 years and born in nine different geographical regions of the world were examined, and we computed age-standardized incidence rates for the different geographic regions-denoted ethnic groups in the paper. Gender-stratified Cox regression analysis, adjusted for age, was used to model risk of hip fracture as a function of region of birth.

RESULTS

Age-standardized incidence rates of hip fracture varied considerably between regions of birth living in Norway, in both genders. All immigrant groups had lower risk of hip fracture compared to the Norwegian-born population. Immigrants from Central and Southeast Asia had the lowest risk of hip fracture when compared to individuals born in Norway (HR = 0.2, 95% CI 0.1-0.3 and HR =0.2, 95% CI 0.2-0.4 in men and women, respectively).

CONCLUSION

Lower risk of hip fracture was found in all immigrant groups compared to the Norwegian-born majority population.

Over-coverage in population registers leads to bias in demographic estimates

Estimating the number of individuals living in a country is an essential task for demographers. This study assesses the potential bias in estimating the size of different migrant populations due to over-coverage in population registers. Over-coverage-individuals registered but not living in a country-is an increasingly pressing phenomenon; however, there is no common understanding of how to deal with over-coverage in demographic research. This study examines different approaches to and improvements in over-coverage estimation using Swedish total population register data. We assess over-coverage levels across migrant groups, test how estimates of age-specific death and fertility rates are affected when adjusting for over-coverage, and examine whether over-coverage can explain part of the healthy migrant paradox. Our results confirm the existence of over-coverage and we find substantial changes in mortality and fertility rates, when adjusted, for people of migrating age. Accounting for over-coverage is particularly important for correctly estimating migrant fertility.

Sex differences in mortality in migrants and the Swedish-born population: Is there a double survival advantage for immigrant women?

OBJECTIVES

In the present study, we examine whether the relationships between country of origin or reason for migration and mortality differ between men and women.

METHODS

We apply hazard regression models on high-quality Swedish register data with nationwide coverage.

RESULTS

Relative to their Swedish counterparts, migrants from Nordic and East European (EU) countries and former Yugoslavia have higher mortality. This excess mortality among migrants relative to Swedes is more pronounced in men than in women. Migrants from Western and Southern European countries; Iran, Iraq, and Turkey; Central and South America; and Asia, have lower mortality than Swedes, and the size of the mortality reduction is similar in both sexes. The predictive effects of the reason for migration for mortality are also similar in migrant men and women.

CONCLUSIONS

This study provides little support for the hypothesis of a double survival advantage among immigrant women in Sweden. However, it does show that the excess mortality in migrants from Nordic and EU countries and former Yugoslavia relative to the Swedish-born population is more pronounced in men than in women.

Mortality advantage among migrants according to duration of stay in France, 2004-2014

Background

The migrant mortality advantage is generally interpreted as reflecting the selection of atypically healthy individuals from the country of origin followed by the wearing off of selection effects over time, a process theorised to be accelerated by progressive and negative acculturation in the host country. However, studies examining how migrant mortality evolves over duration of stay, which could provide insight into these two processes, are relatively scarce. Additionally, they have paid little attention to gender-specific patterns and the confounding effect of age. In this study, we analyze all-cause mortality according to duration of stay among male and female migrants in France, with a particular focus on the role of age in explaining duration of stay effects.

Methods

We use the Échantillon Démographique Permanent (Permanent Demographic Sample; EDP), France’s largest socio-demographic panel and a representative 1% sample of its population. Mortality was followed-up from 2004 to 2014, and parametric survival models were fitted for males and females to study variation in all-cause mortality among migrants over duration of stay. Estimates were adjusted for age, duration of stay, year, education level and marital status. Duration of stay patterns were examined for both open-ended and fixed age groups.

Results

We observe a migrant mortality advantage, which is most pronounced among recent arrivals and converges towards the mortality level of natives with duration of stay. We show this pattern to be robust to the confounding effect of age and find the pattern to be consistent among males and females.

Conclusions

Our novel findings show an intrinsic pattern of convergence of migrant mortality towards native-born mortality over time spent in France, independent from the ages at which mortality is measured. The consistent pattern in both genders suggests that males and females experience the same processes associated with generating the migrant mortality advantage. These patterns adhere to the selection-acculturation hypothesis and raise serious concerns about the erosion of migrant health capital with increasing exposure to conditions in France.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6652-1) contains supplementary material, which is available to authorized users.

The definition of immigrant status matters: impact of nationality, country of origin, and length of stay in host country on mortality estimates

BACKGROUND

Mortality is a robust indicator of health and offers valuable insight into the health of immigrants. However, mortality estimates can vary significantly depending on the manner in which immigrant status is defined. Here, we assess the impact of nationality, country of origin, and length of stay in the host country on mortality estimates in an immigrant population in Aragón, Spain.

METHODS

Cross-sectional retrospective study of all adult subjects from the EpiChron Cohort in 2011 (n = 1,102,544), of whom 146,100 were foreign-born (i.e., according to place of birth) and 127,213 were non-nationals (i.e., according to nationality). Directly standardized death proportions between years 2012-2015 were calculated, taking into account the age distribution of the European population in 2013. Binary logistic regression was used to compare the four-year probability of death.

RESULTS

The age- and sex-standardized number of deaths per 1000 subjects were 45.1 (95%CI 44.7-45.2) for the Spanish-born population, 29.3 (95%CI 26.7-32.1) for the foreign-born population, and 18.4 (95%CI 15.6-21.6) for non-Spanish nationals. Compared with the Spanish-born population, the age- and sex-adjusted likelihood of dying was equally reduced in the foreign-born and non-national populations (OR 0.6; 95%CI 0.5-0.7) when the length of stay was less than 10 years. No significant differences in mortality estimates were detected when the length of stay was over 10 years.

CONCLUSIONS

Mortality estimates in immigrant populations were lower than those of the native Spanish population, regardless of the criteria applied. However, the proportion of deaths was lower when immigrant status was defined using nationality instead of country of birth. Age- and sex-standardized death proportions tended to increase with increased length of stay in the host country.

Trends in mortality inequalities in an urban area: the influence of immigration

BACKGROUND

Nearly 20% of the population in Barcelona is foreign-born and this percentage rises to up to 40% in some neighborhoods. Consequently, migration health patterns may play an important role in trends in socioeconomic geographical inequalities in mortality. The objective of this study was to analyze the trend in socioeconomic inequalities in mortality between neighborhoods in Barcelona during the period 2001-2012 in the foreign-born and Spanish-born population.

METHODS

Repeated cross-sectional design of the population aged 25-64 years in Barcelona between 2001 and 2012. Hierarchical data consisted of yearly mortality linked-population. The variables analyzed were age, sex, education, and country of birth (Spanish-born, foreign-born), neighborhood of residence, and the socioeconomic level of the neighborhoods using quartiles of unemployment rates. Age-standardized mortality rates were estimated, and mixed Poisson regressions were applied using generalized linear mixed models, including two random effects to consider the intracorrelation within neighborhoods and across years.

RESULTS

The number of foreign-born residents aged 25-64 increased notably in disadvantaged neighborhoods. Approximately 9% of premature deaths occurred in foreign-born individuals. Premature mortality rates were higher in disadvantaged neighborhoods and in the Spanish-born population in all periods. Despite the stabilized socioeconomic inequalities in mortality in the Spanish-born population, no inequalities were found between neighborhoods in foreign-born men and women.

CONCLUSIONS

Evidence of the 'healthy migrant' effect in mortality and socioeconomic inequalities in mortality was found in Barcelona, which seems to alter the distribution of mortality through time and space, related to the low levels of premature mortality and the selective residence of immigrants in socioeconomically disadvantaged neighborhoods.

Differences in cancer survival between immigrants in Norway and the host population

Cancer survival is an important indicator for quality of cancer care. We sought to determine if there are differences in cancer survival between immigrants and the host population in Norway. We performed a nationwide registry-based study comprising subjects diagnosed with cancer between 1990 and 2014, and followed until the end of 2016. Survival was estimated for 13 cancer sites with cause-specific survival. Adjustments were made for common confounders (age, sex, year of diagnosis and place of residence) and defined mediators (stage at diagnosis, comorbidity and socioeconomic factors). A total of 500,255 subjects were available for analysis, of which 11,252 were Western and 8,701 non-Western immigrants. We did not find differences in cancer survival between Western immigrants and Norwegians, while non-Western immigrants, with some exceptions, had similar or better survival. Better lung cancer survival in non-Western immigrants than Norwegians was notable (hazard ratio (95% confidence interval): 0.78 (0.71-0.85)), and not explained by defined mediators. Immigrants from Eastern Europe and Balkan with melanoma (hazard ratio: 1.54 (1.12-2.12)) and prostate cancer (hazard ratio: 1.34 (1.08-1.67)), and possibly from sub-Saharan Africa with breast cancer (hazard ratio: 1.41 (0.94-2.12)) had worse survival than Norwegians. The results suggest that immigrants in Norway have good cancer survival relative to the host population. Poor survival in immigrants from Eastern Europe and Balkan with melanoma and prostate cancer, and sub-Saharan Africa with breast cancer might be a concern.

An observational study of immigrant mortality differences in Norway by reason for migration, length of stay and characteristics of sending countries

BACKGROUND

Knowledge of mortality differentials in immigrant groups depending on their reason for migration, length of stay in host countries and characteristics of sending countries may be beneficial for policy interventions aimed to improve various immigrant groups' health and welfare.

METHODS

We employed discrete-time hazard regression models with time-varying covariates to compare the death risk of immigrants to those of Norwegian-born natives using linked register data on the Norwegian population aged 25-79 during 1990-2015. More than 492,000 deaths occurred in around 4.6 million individuals. All analyses were adjusted for sex, age, calendar time and sociodemographic characteristics.

RESULTS

Immigrants had an 11% survival advantage overall. Those immigrating due to work or education had the lowest death risk, whereas refugees had the highest death risk (albeit lower than that of natives). Death risks increased markedly with length of stay, and were most pronounced for those having spent more than 40% of their lives in Norway. Net of reason for migration, only minor differences were observed depending on Human Development Index characteristics of sending countries.

CONCLUSION

Independent of reason for migration and characteristics of sending countries, those who immigrate to Norway in adulthood appear to be particularly healthy. The higher death risk associated with prolonged lengths of stay suggests that disadvantageous 'acculturation' or stress factors related to the post-migration period may play a role in the long run. The health and welfare of long-term immigrants thus warrants further research.

Distinctive role of income in the all-cause mortality among working age migrants and the settled population in Finland: A follow-up study from 2001 to 2014

BACKGROUND

Although income level may play a significant part in mortality among migrants, previous research has not focused on the relationship between income, migration and mortality risk. The aim of this register study was to compare all-cause mortality by income level between different migrant groups and the majority settled population of Finland.

METHODS

A random sample was drawn of 1,058,391 working age people (age range 18-64 years; 50.4% men) living in Finland in 2000 and linked to mortality data from 2001 to 2014. The data were obtained from Statistics Finland. Cox proportional hazards models were used to investigate the association between region of origin and all-cause mortality in low- and high-income groups.

RESULTS

The risk for all-cause mortality was significantly lower among migrants than among the settled majority population (hazards ratio (HR) 0.57; 95% confidence interval (CI) 0.53-0.62). After adjustment for age, sex, marital status, employment status and personal income, the risk of mortality was significantly reduced for low-income migrants compared with the settled majority population with a low income level (HR 0.46; 95% CI 0.42-0.50) and for high-income migrants compared with the high-income settled majority (HR 0.81; 95% CI 0.69-0.95). Results comparing individual high-income migrant groups and the settled population were not significant. Low-income migrants from Africa, the Middle East and Asia had the lowest mortality risk of any migrant group studied (HR 0.32; 95% CI 0.27-0.39).

CONCLUSIONS

Particularly low-income migrants seem to display a survival advantage compared with the corresponding income group in the settled majority population. Downward social mobility, differences in health-related lifestyles and the healthy migrant effect may explain this phenomenon.

Ethnic differences in the incidence of cancer in Norway

Traditionally there have been differences in cancer incidence across geographic regions. When immigrants have moved from low-income to high-income countries, their incidence have changed as they have adapted to the lifestyle in the new host country. Given worldwide changes in lifestyle factors over time, we decided to examine cancer incidence in immigrant groups in Norway, a country with a recent immigration history, complete cancer registration and universal public health care. We linked immigration history for the complete population to information on cancer diagnosis from the Cancer Registry of Norway for the period 1990-2012. Age-standardized (world) overall and site-specific cancer incidence were estimated for different immigrant groups and compared to incidence among individuals born in Norway. Among 850,008 immigrants, 9,158 men and 10,334 women developed cancer, and among 5,508,429 Norwegian-born, 263,316 men and 235,020 women developed cancer. While incidence of breast and colorectal cancer were highest among individuals born in Norway and other high-income countries, other cancer types were higher in immigrants from low-income countries. Lung cancer incidence was highest in Eastern European men, and men and women from Eastern Europe had high incidence of stomach cancer. Incidence of liver cancer was substantially higher in immigrants from low-income countries than in individuals born in Norway and other high-income countries. Our results mirror known cancer challenges across the world. Although cancer incidence overall is lower in immigrants from low-income countries, certain cancers, such as lung, liver and stomach cancer, represent major challenges in specific immigrant groups.