Is migration to Sweden associated with increased prevalence of risk factors for cardiovascular disease?

Empirical evidence of predictive adaptive response in humans: systematic review and meta-analysis of migrant populations

Meta-analysis is used to test a variant of a Developmental Origins of Adult Health and Disease (DOHaD)'s conjecture known as predictive adaptive response (PAR). According to it, individuals who are exposed to mismatches between adverse or constrained in utero conditions, on the one hand, and postnatal obesogenic environments, on the other, are at higher risk of developing adult chronic conditions, including obesity, type 2 diabetes (T2D), hypertension and cardiovascular disease. We argue that migrant populations from low and middle to high-income countries offer a unique opportunity to test the conjecture. A database was constructed from an exhaustive literature search of peer-reviewed papers published prior to May 2021 contained in PUBMED and SCOPUS using keywords related to migrants, DOHaD, and associated health outcomes. Random effects meta-regression models were estimated to assess the magnitude of effects associated with migrant groups on the prevalence rate of T2D and hypertension in adults and overweight/obesity in adults and children. Overall, we used 38 distinct studies and 78 estimates of diabetes, 59 estimates of hypertension, 102 estimates of overweight/obesity in adults, and 23 estimates of overweight/obesity in children. Our results show that adult migrants experience higher prevalence of T2D than populations at destination (PR 1.48; 95% CI 1.35-1.65) and origin (PR 1.80; 95% CI 1.40-2.34). Similarly, there is a significant excess of obesity prevalence in children migrants (PR 1.22; 95% CI 1.04-1.43) but not among adult migrants (PR 0.89; 95% CI 0.80-1.01). Although the total effect of migrant status on prevalence of hypertension is centered on zero, some migrant groups show increased risks. Finally, the size of estimated effects varies significantly by migrant groups according to place of destination. Despite limitations inherent to all meta-analyses and admitting that some of our findings may be accounted for alternative explanations, the present study shows empirical evidence consistent with selected PAR-like conjectures.

Inequalities in COVID-19 severe morbidity and mortality by country of birth in Sweden

Migrants have been more affected by the COVID-19 pandemic. Whether this has varied over the course of the pandemic remains unknown. We examined how inequalities in intensive care unit (ICU) admission and death related to COVID-19 by country of birth have evolved over the course of the pandemic, while considering the contribution of social conditions and vaccination uptake. A population-based cohort study was conducted including adults living in Sweden between March 1, 2020 and June 1, 2022 (n = 7,870,441). Poisson regressions found that migrants from Africa, Middle East, Asia and European countries without EU28/EEA, UK and Switzerland had higher risk of COVID-19 mortality and ICU admission than Swedish-born. High risks of COVID-19 ICU admission was also found in migrants from South America. Inequalities were generally reduced through subsequent waves of the pandemic. In many migrant groups socioeconomic status and living conditions contributed to the disparities while vaccination campaigns were decisive when such became available.

Uptake and effectiveness of a primary cardiovascular prevention program in an underserved multiethnic urban community

BACKGROUND AND AIMS

Cardiometabolic risk is increased among disadvantaged people and ethnic minorities. Paradoxically, their uptake of primary cardiovascular prevention is relatively low. New strategies are needed to tackle this public health problem. Aims of this study were to assess the uptake (as well as its determinants) and effectiveness of a primary cardiovascular prevention program for communities devised to facilitate access of disadvantaged and inclusion of ethnic minorities in addition to providing a state-of-the-art interdisciplinary personalized care.

METHODS AND RESULTS

Single center, hospital-based, open study. All the residents in an underserved multiethnic urban community aged 40-65 years (n = 1646, 43.6% immigrants) were proactively invited by post mail to participate in a cardiovascular prevention program and different approaches were adopted to promote accessibility and inclusiveness. Program uptake was 23% and individual features independently associated with program uptake were status of immigrant (OR [CI 95%]: 3.6 [2.6-5.1]), higher educational level (3.6 [2.8-4.7]), and female gender (1.6 [1.2-2.1]). Retention was 82% at 6 months and 69% at 12 months. A predefined outcome of global cardiovascular risk improvement at 12 months in subjects with glycaemia >126 mg/dl, LDL-C >115 mg/dl, systolic blood pressure ≥140 mmHg or BMI >28 at baseline was reached in 35%, 33%, 37% and 7% of the patients, respectively. 20% of smokers quitted and significant favorable changes were reported in diet quality, anxiety, depression and physical activity.

CONCLUSION

Access inequalities to effective prevention may be counteracted, but increasing global uptake requires further upstream sensitization and awareness actions. REGISTERED IN CLINICALTRIALS.GOV: NCT03129165.

Socioeconomic and demographic risk factors in COVID-19 hospitalization among immigrants and ethnic minorities

BACKGROUND

Immigrants and ethnic minorities have been shown to be at increased risk of hospitalization from COVID-19. Our aim was to analyse the contribution of socioeconomic and demographic risk factors on hospital admissions for COVID-19 among immigrants and ethnic minorities compared to the majority population.

METHODS

We used nationwide register data on all hospitalized COVID-19 cases between February and June 2020 (N = 2232) and random controls from the general population (N = 498 117). We performed logistic regression analyses and adjusted for age, sex, comorbidity, and socioeconomic and demographic factors. The main outcome measure was hospitalization with COVID-19 and was estimated using odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

Among 2232 COVID-19 cases, the OR of hospitalization with COVID-19 among immigrants and descendants of non-Western origin was 2.5 times higher (95% CI: 2.23-2.89) compared with individuals of Danish origin with most pronounced results among individuals from Iraq, Morocco, Pakistan and Somalia. The OR was largely attributed to comorbidity and socioeconomic factors, especially household size, occupation, and population density.

CONCLUSION

There is a significantly higher OR of hospitalization with COVID-19 among non-Western immigrants and ethnic minorities compared with ethnic Danes. This knowledge is crucial for health policymakers and practitioners in both the current and future pandemics to identify more vulnerable groups and target prevention initiatives.

Disparities in Coronavirus Disease 2019 Mortality by Country of Birth in Stockholm, Sweden: A Total-Population-Based Cohort Study

Preliminary evidence points to higher morbidity and mortality from coronavirus disease 2019 (COVID-19) in certain racial and ethnic groups, but population-based studies using microlevel data are lacking so far. We used register-based cohort data including all adults living in Stockholm, Sweden, between January 31, 2020 (the date of the first confirmed case of COVID-19) and May 4, 2020 (n = 1,778,670) to conduct Poisson regression analyses with region/country of birth as the exposure and underlying cause of COVID-19 death as the outcome, estimating relative risks and 95% confidence intervals. Migrants from Middle Eastern countries (relative risk (RR) = 3.2, 95% confidence interval (CI): 2.6, 3.8), Africa (RR = 3.0, 95% CI: 2.2, 4.3), and non-Sweden Nordic countries (RR = 1.5, 95% CI: 1.2, 1.8) had higher mortality from COVID-19 than persons born in Sweden. Especially high mortality risks from COVID-19 were found among persons born in Somalia, Lebanon, Syria, Turkey, Iran, and Iraq. Socioeconomic status, number of working-age household members, and neighborhood population density attenuated up to half of the increased COVID-19 mortality risks among the foreign-born. Disadvantaged socioeconomic and living conditions may increase infection rates in migrants and contribute to their higher risk of COVID-19 mortality.

Extent of the association between self-rated health and place of birth: a cross-sectional study among people at high risk of developing pre-diabetes and diabetes in Sweden

OBJECTIVE

The first aim was to determine the extent of the relationship between place of birth and self-rated health (SRH) in primary healthcare patients born outside Sweden and those born in Sweden. The second aim was to investigate whether socioeconomic and lifestyle factors explained any differences.

SETTING

Two academic primary healthcare centres in Stockholm County, Sweden.

PARTICIPANTS

825 patients at high risk of developing pre-diabetes and diabetes, aged 18-74 years, attending academic healthcare centres in areas with large numbers of immigrants, 56.8% born abroad and 43.2% born in Sweden. Patients with a diagnosis of diabetes were excluded. Inclusion criteria were based on previous research showing that people born in Middle Eastern and Asian countries who live in Sweden have a high prevalence of and risk for diabetes.

OUTCOME

SRH was dichotomised as optimal (very good/good) and suboptimal (fair/bad/very bad) and compared in those born outside Sweden and in Sweden.

RESULTS

There was a statistically significant difference in the SRH of the two groups (p=0.008). Logistic regression analysis showed a crude OR for reduced SRH of 1.46 (95% CI 1.10 to 1.92) in patients born outside Sweden. After controlling for education, employment and marital status, the OR increased to 1.50 (95% CI 1.11 to 2.02). After controlling for physical activity and smoking, it decreased to 1.36 (95% CI 1.00 to 1.85).

CONCLUSION

Socioeconomic and lifestyle factors influenced SRH. It could therefore be useful for clinicians to consider these factors when providing care for patients born outside Sweden and resettled in areas with large numbers of immigrants.

Immigrant health, our health

This final chapter reviews the main conclusions reached by the Special Issue articles in the areas of EUNAM (EU and North African Migrants: Health and Health Systems) activities, covering well-being, health status, disease panorama and use of health services of immigrants to the EU. The reviewed chapters show that immigrants are a vulnerable population experiencing, in some aspects, discrimination and hardship similar to the socially weakest national population groups. Immigration has changed the disease spectrum, particularly in infectious diseases and recessive conditions such as sickle cell disease and familial Mediterranean fever. Importantly, health questions of immigrants cannot be separated from those of any human health issues. An imminent new immigrant question for the EU will be the massive internal migration. Although the overall disease spectrum may not be vastly different between EU countries, the internal migrants will be exposed to lifestyle-dependent ill health and diseases probably in a similar way as did migrants from outside Europe. Migrant health research requires dedicated funding, which needs to come from central EU sources because multiple nationalities are involved. This funding should be able to project the course of health from the country of origin to the country of destination and back again, which was one of guidelines in the funding that initiated EUNAM.

Acculturation and nutritional health of immigrants in Canada: a scoping review

Although recent immigrants to Canada are healthier than Canadian born (i.e., the Healthy Immigrant Effect), they experience a deterioration in their health status which is partly due to transitions in dietary habits. Since pathways to these transitions are under-documented, this scoping review aims to identify knowledge gaps and research priorities related to immigrant nutritional health. A total of 49 articles were retrieved and reviewed using electronic databases and a stakeholder consultation was undertaken to consolidate findings. Overall, research tends to confirm the Healthy Immigrant Effect and suggests that significant knowledge gaps in nutritional health persist, thereby creating a barrier to the advancement of health promotion and the achievement of maximum health equity. Five research priorities were identified including (1) risks and benefits associated with traditional/ethnic foods; (2) access and outreach to immigrants; (3) mechanisms and coping strategies for food security; (4) mechanisms of food choice in immigrant families; and (5) health promotion strategies that work for immigrant populations.

Factors associated with self-rated health among North Korean defectors residing in South Korea

BACKGROUND

The number of North Korean refugees entering South Korea has increased recently. The health status of refugees is a significant factor in determining their success in resettlement; therefore, this study examined both the self-rated health status of North Korean defectors who have settled in South Korea and the factors associated with their self-rated health status.

METHODS

This study utilized data gained from face-to-face interviews with 500 North Korean defectors who arrived in South Korea in 2007. The interviews were structured and conducted by 'Yonsei University Research Team for North Korean defectors'. A stepwise multivariable linear regression was performed to determine the factors associated with their self-rated health status.

RESULTS

North Korean defectors who were female, elderly, or had low annual household income, disability or chronic diseases reported lower health status. However, self-rated health status was higher among those who had settled in South Korea for 18 months or more, who were satisfied with government support or their current life, and who had experienced more traumatic events in North Korea.

CONCLUSIONS

Government policies and refugee assistance programs should consider and reflect the factors relevant to the health status of North Korean defectors.

Epidemiological studies of migration and environmental risk factors in the inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are idiopathic chronic diseases of the gastrointestinal tract well known to be associated with both genetic and environmental risk factors. Permissive genotypes may manifest into clinical phenotypes under certain environmental influences and these may be best studied from migratory studies. Exploring differences between first and second generation migrants may further highlight the contribution of environmental factors towards the development of IBD. There are few opportunities that have been offered so far. We aim to review the available migration studies on IBD, evaluate the known environmental factors associated with IBD, and explore modern migration patterns to identify new opportunities and candidate migrant groups in IBD migration research.

Migration and health: a study of effects of early life experiences and current socio-economic situation on mortality of immigrants in Sweden

OBJECTIVES

Previous research has demonstrated mortality differences between immigrants and natives living in Sweden. The aim of this study is to investigate the effects of early life conditions in the country of birth and current socio-economic conditions in adult life in Sweden on cardiovascular, cancer, all other cause and total mortality among immigrants and natives in Sweden.

DESIGN

The cohort data concerning individual demographic characteristics and socio-economic conditions stems from the Swedish Longitudinal Immigrant Database (SLI), a register-based representative database, and consists of individuals from 11 countries of birth, born between 1921 and 1939, who were residents in Sweden between 1980 and 2001. The associations between current socio-economic conditions as well as infant mortality rates (IMR) and Gross Domestic Product (GDP) per capita in the year and country of birth, and total, cardiovascular, cancer and 'all other' mortality in 1980-2001 were calculated by survival analysis using Cox proportional hazards regression to calculate hazard rate ratios.

RESULTS

The effects of current adult life socio-economic conditions in Sweden on mortality are both stronger and more straightforward than the effects of early life conditions in the sense that higher socio-economic status is significantly associated with lower mortality in all groups of diagnoses; however, we find associations between infant mortality rates (IMR) in the year and country of birth, and cancer mortality among men and women in the final model.

CONCLUSIONS

Socioeconomic conditions in Sweden are more strongly associated with mortality than early life indicators IMR and GDP per capita in the year of birth in the country of origin. This finding has health policy and other policy implications.

Risk of inflammatory bowel disease in first- and second-generation immigrants in Sweden: a nationwide follow-up study

BACKGROUND

The objective was to analyze whether there is an association between country of birth in first-generation immigrants and first hospitalization for an inflammatory bowel disease, and to study whether any such association remains in second-generation immigrants.

METHODS

In this follow-up study a nationwide research database at Lund University was used to identify all primary hospital diagnoses of Crohn's disease (CD) and ulcerative colitis (UC) in all first- and second-generation immigrants in Sweden between January 1, 1964, and December 31, 2007. Standardized incidence ratios (SIRs) with regard to age, gender, time period, geographical region, and socioeconomic status were estimated in first- and second-generation immigrants.

RESULTS

No increased but some decreased risks for CD and UC were found among first-generation immigrants. These decreased risks partly remained in the second generation. Moreover, second-generation immigrants of Danish, Eastern European, and Iraqi origin had higher risks of CD than the reference group. Second-generation immigrants of Finnish and Iranian origin had higher risks of UC.

CONCLUSIONS

Decreased risks of CD and UC found in some first-generation immigrant groups partly persisted in the second generation. For some immigrant groups, increased risks of CD or UC emerged in the second generation.

Cardiovascular disease by diabetes status in five ethnic minority groups compared to ethnic Norwegians

Background

The population in Norway has become multi-ethnic due to migration from Asia and Africa over the recent decades. The aim of the present study was to explore differences in the self-reported prevalence of cardiovascular disease (CVD) and associated risk factors by diabetes status in five ethnic minority groups compared to ethnic Norwegians.

Methods

Pooled data from three population-based cross-sectional studies conducted in Oslo between 2000 and 2002 was used. Of 54,473 invited individuals 24,749 (45.4%) participated. The participants self-reported health status, underwent a clinical examination and blood samples were drawn. A total of 17,854 individuals aged 30 to 61 years born in Norway, Sri-Lanka, Pakistan, Iran, Vietnam or Turkey were included in the study. Chi-square tests, one-way ANOVAs, ANCOVAs, multiple and logistic regression were used.

Results

Age- and gender-standardized prevalence of self-reported CVD varied between 5.8% and 8.2% for the ethnic minority groups, compared to 2.9% among ethnic Norwegians (p < 0.001). Prevalence of self-reported diabetes varied from 3.0% to 15.0% for the ethnic minority groups versus 1.8% for ethnic Norwegians (p < 0.001). Among individuals without diabetes, the CVD prevalence was 6.0% versus 2.6% for ethnic minorities and Norwegians, respectively (p < 0.001). Corresponding CVD prevalence rates among individuals with diabetes were 15.3% vs. 12.6% (p = 0.364). For individuals without diabetes, the odds ratio (OR) for CVD in the ethnic minority groups remained significantly higher (range 1.5-2.6) than ethnic Norwegians (p < 0.05), after adjustment for age, gender, education, employment, and body height, except for Turkish individuals. Regardless of diabetes status, obesity and physical inactivity were prevalent in the majority of ethnic minority groups, whereas systolic- and diastolic- blood pressures were higher in Norwegians. In nearly all ethnic groups, individuals with diabetes had higher triglycerides, waist-to-hip ratio (WHR), and body mass index compared to individuals without diabetes. Age, diabetes, hypertension, hypercholesterolemia, and WHR were significant predictors of CVD in both ethnic Norwegians and ethnic minorities, but significant ethnic differences were found for age, diabetes, and hypercholesterolemia.

Conclusions

Ethnic differences in the prevalence of CVD were prominent for individuals without diabetes. Primary CVD prevention including identification of undiagnosed diabetes should be prioritized for ethnic minorities without known diabetes.

Dietary differences between elderly Iranians living in Sweden and Iran a cross-sectional comparative study

BACKGROUND

During the last decades, global migration has increased and many immigrant groups have a higher prevalence than the native born population of several cardiovascular disease risk factors, including poor dietary habits. However, it is uncertain if dietary habits in immigrant populations reflect dietary habits in their country of origin or if the current diet is a consequence of the migration and possible change of dietary habits. The aim of this study was to examine possible dietary differences between elderly Iranians living in Stockholm, Sweden with elderly Iranians living in Tehran, Iran, taking into account sex, age, marital status, and education.

METHODS

Dietary intakes were assessed by semi--quantitative food frequency questionnaire in a cross-sectional study of 121 Iranians living in Stockholm and 52 Iranians living in Tehran, aged 60-80. Differences in dietary habits between the two groups was analysed by bootstrapped regression analyses with 1000 replications.

RESULTS

Iranians living in Sweden had significantly higher intake of protein, total fat, fiber than Iranians living in Iran, but lower consumption of carbohydrates. The observed differences in intake of macronutrients were reflected in consumed amount of all food items, which were higher among Iranians living in Iran with the exception of bread and grain consumption which was lower.

CONCLUSIONS

There are general differences in dietary habits between Iranians living in Iran and Iranians living in Sweden. Parts of observed differences in dietary habits may reflect a favourable adoption process to the Swedish dietary habits after migration. Meanwhile other differences are point of concern in light of the high prevalence of overweight, among Iranians living in Sweden and can have unfavourable impact in particular in the context of cardiovascular health.

Diabetes and impaired glucose tolerance among Turkish immigrants in Sweden

AIM

To investigate whether the prevalence of diabetes and impaired glucose tolerance (IGT) was higher among Turkish immigrants in Sweden, than in their area of origin in Turkey.

METHODS

238 Turkish immigrants aged 20 years and older living in Flemingsberg, Sweden, were compared with 1549 participants of the same age living in the Konya area of Turkey. Data collection included anthropometric measurements, blood pressure (BP) measurements, and an oral glucose tolerance test (OGTT).

RESULTS

Prevalence of laboratory-verified diabetes was 11.8% among participants in Sweden compared to 7.1% among participants in Turkey (p 0.018). Turkish women in Sweden had a higher prevalence of diabetes than Turkish women in Turkey, 12.8% vs. 7.6% (p=0.037). Similarly, IGT was 17.8% among Turkish men in Sweden compared to 4.9% among men in Turkey (p<0.001) and 2-h blood glucose was higher among the immigrants (p<0.001). Systolic BP was also higher among the immigrants, especially in men (p<0.001) who also had a higher BMI (p=0.003).

CONCLUSIONS

The higher prevalence of diabetes and IGT among Turkish immigrants in Flemingsberg, Sweden, suggests that migration is associated with diabetes and that there are important implications for public health in Sweden.

Effects of a lifestyle modification trial among phenotypically obese metabolically normal and phenotypically obese metabolically abnormal adolescents in comparison with phenotypically normal metabolically obese adolescents

This study aimed to assess the effects of a 2-month lifestyle modification trial on cardio-metabolic abnormalities and C-reactive protein (CRP) among obese adolescents with metabolic syndrome [phenotypically obese metabolically abnormal (POMA)] and obese adolescents without a cardio-metabolic disorder [phenotypically obese metabolically normal (POMN)], as well as in normal-weight adolescents with at least one cardio-metabolic disorder [phenotypically normal metabolically obese (PNMO)]. The study comprised 360 adolescents assigned in three groups of equal number of POMN, POMA and PNMO. They were enrolled in a trial consisting of aerobic activity classes, diet and behaviour modification, and were recalled after 6 months. Overall, 94.7% of participants completed the 2-month trial, and 87.3% of them returned after 6 months. The mean CRP was not significantly different between the POMA and PNMO groups, but was higher than in the POMN group. After the trial, body mass index (BMI) and waist circumference (WC) decreased in obese participants, and the mean body fat mass decreased in all groups. At 2 months, the mean total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and CRP decreased in the POMA and PNMO groups. After 2 and 6 months, the decrease in mean TC, LDL-C, TG, CRP and systolic blood pressure was greater in the POMA than in the POMN group. The magnitude of decrease in CRP correlated with that of BMI, WC, fat mass, TG, TC and LDL-C. Lifestyle modification programmes for primordial/primary prevention of chronic diseases would be beneficial at the population level and should not be limited to obese children.

Migration background: a risk factor for caries development during adolescence

The influence of child and parental migration background on the risk of approximal caries increment in Swedish adolescents was investigated. This retrospective longitudinal register-based cohort study included all 13-yr-old adolescents (n = 18,142) who were resident in the County of Stockholm, Sweden, in 2000, and followed them up to 19 yr of age. At follow-up, 15,538 subjects were examined. Caries data [decayed, missing, and filled teeth/surfaces (DMFT/S)], were collected from a dental database. Socio-demographic determinants were collected from Swedish National Registers. After adjustments for socio-demographic confounders, logistic regression analysis revealed that adolescents with foreign-born parents, irrespective of whether the child was born in Sweden or abroad, exhibited a significantly elevated risk for approximal caries increment (DMFSa > 0), and developed, on average, 0.53 and 1.14 more approximal caries lesions, respectively, compared with their counterparts with Swedish-born parents. Furthermore, adolescents born in eastern Europe exhibited an increased risk for approximal caries increment (DMFSa > 0) and developed, on average, 1.06 more approximal caries lesions compared with Swedish-born adolescents. In conclusion, parental migration background must be considered as a risk factor for caries development during adolescence, irrespective of whether or not the adolescent was born in Sweden.

First nationwide study of the prevalence of the metabolic syndrome and optimal cutoff points of waist circumference in the Middle East: the national survey of risk factors for noncommunicable diseases of Iran

OBJECTIVE

The purpose of this study was to provide the first national estimate on the prevalence of the metabolic syndrome and its components and the first ethnic-specific cutoff point for waist circumference in the Eastern Mediterranean Region.

RESEARCH DESIGN AND METHODS

This national survey was conducted in 2007 on 3,024 Iranians aged 25-64 years living in urban and rural areas of all 30 provinces in Iran. The metabolic syndrome was defined by different criteria, namely the definition of the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III), the International Diabetes Federation (IDF) criteria, and the modified definition of the NCEP/ATP III (ATP III/American Heart Association [AHA]/National Heart, Lung, and Blood Institute [NHLBI]).

RESULTS

The age-standardized prevalence of the metabolic syndrome was about 34.7% (95% CI 33.1-36.2) based on the ATP III criteria, 37.4% (35.9-39.0%) based on the IDF definition, and 41.6% (40.1-43.2%) based on the ATP III/AHA/NHLBI criteria. By all definitions, the prevalence of the metabolic syndrome was higher in women, in urban areas, and in the 55- to 64-year age-group compared with the prevalence in men, in rural areas, and in other age-groups, respectively. The metabolic syndrome was estimated to affect >11 million Iranians. The optimal cutoff point of waist circumference for predicting at least two other components of the metabolic syndrome as defined by the IDF was 89 cm for men and 91 cm for women.

CONCLUSIONS

The high prevalence of the metabolic syndrome with its considerable burden on the middle-aged population mandates the implementation of national policies for its prevention, notably by tackling obesity. The waist circumference cutoff points obtained can be used in the region.

Cervical, endometrial and ovarian cancers among immigrants in Sweden: importance of age at migration and duration of residence

In order to compare the risk of gynaecologic cancer among foreign-born women to the risk among those born in Sweden and to elucidate risk of cancer in relation to age at migration and duration of residence, we followed a cohort of 5.3 million women between 1969 and 2004 in Sweden. Through linkage with the national cancer register, we estimated cancer risk as rate ratios (RRs) with 95% confidence intervals (CIs) using Poisson regression. We reported RRs adjusted for age, calendar year of follow-up and years of education. Overall, 18,247 cases of cervical, 35,290 cases of endometrial and 32,227 cases of ovarian cancers occurred during 117 million person-years of follow-up. We found that adjusted RRs of all the three cancers were lower or the same among foreign-born women compared to those born in Sweden. As for cervical cancer, women aged 35-49 years born in Poland and Bosnia and women aged 50 years or more born in South America showed an increased risk, which was related to increasing age at migration. The risk was lowest among women born in Iran, Iraq, Organisation for Economic Cooperation & Development (OECD) and Finland, and highest among women born in Bosnia and Eastern Europe during their first 5 years since immigration. RRs for endometrial and ovarian cancers did not vary by duration of residence or by age at migration. Health care providers should be aware of the higher risk of cervical cancer among immigrants from high-risk areas, especially among those who immigrate at older ages. On the other hand, protective factors for ovarian and endometrial cancers seem to be retained upon migration.