This prospective cohort study used linked Swedish administrative registers and pension payment data to examine post-retirement migration patterns and health selection among Finnish migrants compared to native-born Swedes. The cohort included individuals born between 1938 and 1955 who were resident in Sweden at age 64, with follow-up from age 65 until death or the end of 2021 (n = 1794,196; 80,313 Finnish-born). Health status was assessed using the Charlson Comorbidity Index (CCI), while pension payments were used to identify country of residence and mortality occurring after emigration. Post-retirement emigration was substantially more common among Finnish migrants (3.0 %) than native-born Swedes (0.3 %), primarily due to return migration to Finland. Contrary to the "salmon bias" hypothesis, poorer health reduced rather than increased the likelihood of emigration for both groups. Among Finnish migrants, lower CCI scores, male sex, being unmarried, and lower income predicted a higher likelihood of post-retirement migration. Sequence analyses revealed three distinct Finnish migration trajectories: early return, late return, and return with onward migration. Mortality did not differ significantly between Finnish migrants who remained in Sweden and those who resided in Finland or other countries; adjusted models even indicated slightly lower mortality among return migrants Extending follow-up abroad with pension data did not change mortality estimates, indicating unrecorded deaths abroad likely did not bias results. The findings indicate positive health selection into return migration and no evidence of a salmon bias effect. Post-retirement migration among Finnish migrants in Sweden is rare and has little impact on migrant-native mortality differences.

BACKGROUND:Ethnic inequalities in COVID-19 outcomes are extensively documented, yet underlying causes remain unclear. We investigated ethnic disparities in clinical severity at admission with COVID-19 and their relation to mechanical ventilation (MV), 60-day mortality, and long COVID. METHODS:Retrospective cohort study of adults (≥18 years) admitted with COVID-19 (March 2020-March 2022). Clinical and sociodemographic data extracted from patient records were linked to national register data. Using logistical regression, competing risk, and Cox proportional hazards models, we estimated risk of high-flow oxygen upon admission, MV, 60-day mortality, and long COVID comparing ethnic minority patients with patients of Danish origin. RESULTS:Of 1610 patients, 39.1% were ethnic minority patients. Ethnic minorities were younger, had longer symptom duration (7 vs 6 days, p < 0.001), and a higher risk of requiring high-flow oxygen upon admission (OR 1.41, 95% CI: 1.12;1.79) than patients of Danish origin until adjusted for age. However, ethnic minorities were not at higher risk of MV (HR 1.00, 95% CI: 0.69;1.44), 60-day mortality (HR 0.81, 95% CI: 0.61;1.09), long COVID (HR 0.82, 95% CI: 0.56;1.19) or related symptom diagnosis (HR 1.32, 95% CI: 0.85;2.05). CONCLUSION:While ethnic minorities presented later and more severely ill at admission with a higher risk of receiving high-flow oxygen, their risk of MV, 60-day mortality, and long COVID were comparable to patients of Danish origin. This was largely explained by a substantial difference in age. Our findings emphasise the need for public health interventions to ensure equitable and timely healthcare access for all populations.

It is well known that countries differed in their response to the COVID-19 pandemic in terms of the timing and intensity of specific measures such as lockdowns, face masks and vaccine rollout. However, previous studies have not investigated systematic differences in the overall pandemic strategies. We use daily data from the Oxford COVID-19 Government Response Tracker (OxCGRT), between January 2020 and December 2022 focusing on 16 key pandemic policies, including containment, economic, and health system measures, and apply a three-dimensional k-means clustering algorithm to identify distinct overarching strategies based on the type, intensity, and timing of the response adopted by different countries. We identify four distinct strategies; 1) the traditional infectious disease control approach, adopted by a wide range of high- and middle-income countries, which emphasises strict containment policies and movement restrictions, 2) the public health-oriented approach, adopted by developed welfare states with ageing populations and high health care expenditures, which is more flexible over time and focuses more on economic and health policies, such as income support and testing strategies, with less emphasis on stringent containment, 3) high stringency with gradual relaxation, and 4) reactive policies at a minimal level, both adopted by less democratic low- and middle income countries with substantial inequalities and with younger and less vulnerable populations. The findings contribute to understanding how different countries adapted to the pandemic and how these responses may relate to broader socio-political contexts, including welfare state arrangements and economic resilience.

Objectives:Polycystic ovary syndrome (PCOS) is an endocrine disorder in women of fertile age which may also affect the labor market attachment. We investigated labor market attachment trajectories among working age women diagnosed with PCOS. Methods:A cohort of 157,356 women born in 1975-1977 were followed annually between the ages of 30 and 39, using data from Swedish administrative registers. Multinomial logistic regression was employed to assess associations between being diagnosed with PCOS (after the age of 15) and belonging to the identified clusters of labor market attachment trajectories. Results:Women with PCOS spent less time in employment and were more dependent on sickness benefits during the follow-up time than those without PCOS. Five labor market attachment clusters were identified: stable employment, education into employment, labor market exclusion, continuously unstable position, long-term sickness. Compared to being in the stable employment cluster, women diagnosed with PCOS were more likely to experience long-term sickness [RRR (relative risk ratio): 1.97 (CI: 1.90-2.05)], and education into employment [RRR: 1.11 (CI: 1.07-1.15)]. Conclusion:PCOS can lead to disadvantaged labor market outcomes. Better strategies are needed to prevent economic exclusion among women diagnosed with PCOS.

BACKGROUND:Many studies have found more severe COVID-19 outcomes in migrants and ethnic minorities throughout the COVID-19 pandemic, while recent evidence also suggests higher risk of longer-term consequences. We studied the risk of a long COVID diagnosis among adult residents in Sweden, dependent on country of birth and accounting for known risk factors for long COVID. METHODS:We used linked Swedish administrative registers between March 1, 2020 and April 1, 2023, to estimate the risk of a long COVID diagnosis in the adult population that had a confirmed COVID-19 infection. Poisson regressions were used to calculate incidence rate ratios (IRR) of long COVID by country/region of birth. The contribution of sex, preexisting health status, disease severity, vaccination status, and socioeconomic factors to differences in long COVID diagnosis by country/region of birth were further investigated. RESULTS:Of the 1,869,188 persons diagnosed with COVID-19 that were included, 7539 had received a long COVID diagnosis. Compared with residents born in Sweden, we found higher risks of long COVID among migrants from East Europe (IRR: 1.44 CI: 1.29-1.60), Finland (IRR: 1.36 CI: 1.15-1.61), South Asia (IRR: 1.28 CI: 1.03-1.59), Other Asia (IRR: 1.35 CI: 1.13-1.62), Other Africa (IRR: 1.48 CI: 1.17-1.87), and the Middle East (IRR: 1.43 CI: 1.27-1.63) in models adjusted for age and sex. We discovered that disease severity, i.e., whether the person was hospitalized (IRR: 18.6 CI: 17.3-20.0) or treated in an intensive care unit (IRR: 120.5 CI: 111.7-129.8), primarily contributed to the higher risk of long COVID found in migrants while the contribution of vaccinations and social conditions were moderate. Preexisting health problems did not contribute to the increased risk of long COVID in migrants. CONCLUSIONS:The greater exposure and impact of the COVID-19 virus among migrants also affected longer-term consequences. Disease severity was the most important risk factor for long COVID in migrants. The findings emphasize the need for targeted health interventions for migrant communities during an infectious disease pandemic, such as strategic vaccination campaigns and extending social insurance schemes, focusing on reducing disease severity to mitigate the longer-term health consequences of an infection.

Background:In recent decades, Sweden has become an increasingly diverse society by origin, but one in which residential segregation by migrant background has also increased. This study examines how different aspects of migrant residential segregation are associated with all-cause mortality among native-born and migrant populations. Methods:Using Swedish population-based registers, this longitudinal open cohort study assessed associations between four local level indices of migrant residential segregation and all-cause mortality among adult migrant and native-born residents of Sweden's three largest metropolitan areas (Stockholm, Gothenburg, and Malmö) between 2004 and 2016. Multilevel Poisson regression models, adjusted for individual-level sociodemographic and socioeconomic factors as well as area-level socioeconomic conditions, were used to estimate associations between these indices and all-cause mortality. Results:Moderate decreased mortality risks were observed among migrants in residential areas with higher levels of migrant density, isolation, and exposure in fully adjusted models. However, isolation and exposure effects could not be distinguished due to a high degree of correlation between the isolation and exposure measures. In fully adjusted models mortality gradients were largely unobserved among native-born individuals in relation to migrant residential segregation. The evenness dimension of segregation showed limited relevance for mortality risk in both groups. Conclusions:This study provides evidence that higher migrant density is associated with lower mortality risks among migrants, suggesting that residential areas with higher proportions of migrants may offer health benefits for migrants. These findings highlight the importance of residential contexts in shaping migrant health outcomes.

There is a scarcity of studies examining the impact of the COVID-19 pandemic on the descendants of immigrants, a group representing a growing segment of the population in many countries. This study utilized a national cohort event history analysis in Sweden, consisting of all residents aged over 20 years at the end of 2019 (n = 7 871 444), with a follow-up period from 31 December 2019 to 1 June 2021. Poisson regression was used to estimate incidence rate ratios for severe COVID-19 morbidity [hospitalization, intensive care unit (ICU) admission] and COVID-19-related mortality based on generation status [first generation (G): foreign-born, arrived as adults; the 1.5 generation: foreign-born, arrived as a child; second generation: native-born to two foreign-born parent; and 2.5 generation: native-born to one foreign-born parents] stratified by their region of origin (Nordics, Global South, and Global North) using the majority population (two native-born parents) as reference. All immigrant generations experienced higher rates for severe COVID-19 morbidity compared to the majority population. While this pattern is observed across all regions of origin, the largest differences appear among individuals with a Global South background. Adjusting for social and health factors moderately attenuates the estimates for the descendants of immigrants. Mixed results are found regarding COVID-19 mortality by region of origin and generational status. All immigrant generations experience a COVID-19 morbidity burden comparable to first-generation immigrants and should thus be considered when planning preventive measures to prepare for future pandemics and health crises.

BACKGROUND: Low socioeconomic status has been demonstrated as a risk factor for COVID-19 severity and mortality. However, whether socioeconomic disparities also influence the risk of long COVID diagnosis among ethnic minorities compared to the native majority population remains unclear. METHODS: We conducted a nationwide register-based cohort study in Denmark, including individuals with a first-time COVID-19 diagnosis between January 2020 and August 2022. The risk of long COVID diagnosis among ethnic groups (defined by country of birth) was compared according to socioeconomic status. RESULTS: Among 2 287 175 COVID-19 cases, 4579 were diagnosed with long COVID. The risk of long COVID diagnosis did not significantly differ by income or educational attainment for most ethnic groups. However, among low-income individuals, migrants had a higher risk of long COVID than native Danes, particularly Eastern Europeans (HR adjusted 1.45, 95 % CI [1.25,1.70], p < 0.001), Southeast Asians (HR adjusted 2.08, 95 % CI [1.32,3.28], p = 0.002), Middle Easterners (HR adjusted 1.65, 95 % CI [1.31,2.07], p < 0.001), and North Africans (HR adjusted 1.68, 95 % CI [1.24,2.27], p < 0.001). Additionally, migrant workers (Eastern European, Middle Eastern, and South Asian) in occupational sectors such as "economy, business, and administration", "operator, driver and transportation service", "sales and customer service", "general office and secretarial service" and "education" had a higher long COVID risk than native Danish workers in the same workplaces. IMPLICATIONS: These findings highlight the need to address ethnic disparities in long COVID, particularly among migrants with low income. Workplace interventions and policies targeting work-related vulnerabilities could help reduce the disproportionate burden of long COVID among migrant workers.

Background: Explanations for the disproportional COVID-19 burden among immigrants relative to host-country natives include differential exposure to the virus and susceptibility due to poor health conditions. Prior to the pandemic, immigrants displayed deteriorating health with duration of residence that may be associated with increased susceptibility over time. The aim of this study was to compare immigrant–native COVID-19 mortality by immigrants’ duration of residence to examine the role of differential susceptibility. Methods: A population-based cohort study was conducted with individuals between 18 and 100 years old registered in Sweden between 1 January 2015 and 15 June 2022. Cox regression models were run to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Inequalities in COVID-19 mortality between immigrants and the Swedish-born population in the working-age group were concentrated among those of non-Western origins and from Finland with more than 15 years in Sweden, while for those of retirement age, these groups showed higher COVID-19 mortality HRs regardless of duration of residence. Both age groups of immigrants from Africa and the Middle East showed consistently higher COVID-19 mortality HRs. For the working-age population: Africa: HR<15: 2.46, 95%CI: 1.78, 3.38; HR≥15: 1.49, 95%CI: 1.01, 2.19; and from the Middle East: HR<15: 1.20, 95%CI: 0.90, 1.60; HR≥15: 1.65, 95%CI: 1.32, 2.05. For the retirement-age population: Africa: HR<15: 3.94, 95%CI: 2.85, 5.44; HR≥15: 1.66, 95%CI: 1.32, 2.09; Middle East: HR<15: 3.27, 95%CI: 2.70, 3.97; HR≥15: 2.12, 95%CI: 1.91, 2.34. Conclusions: Differential exposure, as opposed to differential susceptibility, likely accounted for the higher COVID-19 mortality observed among those origins who were disproportionately affected by the pandemic in Sweden.

Abstract Numerous studies have reported lower overall cancer mortality rates among immigrants compared to native populations. However, limited information exists regarding cancer mortality among immigrants based on specific birth countries and cancer types. We used population‐based registries and followed 10 million individuals aged 20 years or older in Sweden between 1992 and 2016. The Cox proportional hazard model was used to explore the disparities in cancer mortality by country of birth and cancer type, stratified by gender. Age‐standardized mortality rates were also computed using the world standard population. Hazard ratio (HR) of all‐site cancer was slightly lower among immigrants (males: HRm = 0.97: 95% confidence interval: 0.95, 0.98; females: HRf = 0.93: 0.91, 0.94) than Swedish‐born population. However, the immigrants showed higher mortality for infection‐related cancers, including liver (HRf = 1.10: 1.01, 1.19; HRm = 1.10: 1.02, 1.17), stomach (HRf = 1.39: 1.31, 1.49; HRm = 1.33: 1.26, 1.41) cancers, and tobacco‐related cancers, including lung (HRm = 1.44: 1.40, 1.49), and laryngeal cancers (HRm = 1.47: 1.24, 1.75). The HR of mesothelioma was also significantly higher in immigrants (HRf = 1.44: 1.10, 1.90). Mortality from lung cancer was specifically higher in men from Nordic (HRm = 1.41: 1.27, 1.55) and non‐Nordic Europe (HRm = 1.49: 1.43, 1.55) countries and lower in Asian (HRm = 0.78: 0.66, 0.93) and South American men (HRm = 0.70: 0.57, 0.87). In conclusion, there are large variations in cancer mortality by country of birth, and cancer type and require regular surveillance. Our detailed analyses lead to some novel findings such as excess mortality rate of mesothelioma and laryngeal cancers in Immigrants in Sweden. A targeted cancer prevention program among immigrants in Sweden is needed.

Abstract Background Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of fertile age and is associated with several burdensome comorbidities. We use Swedish longitudinal register data to identify and compare clusters of employment trajectories among working age women, in order to investigate how PCOS affects labor market attachment. Data and Methods A cohort of 157,356 women born in 1975-1977 were followed annually between the ages of 30 and 39. Labor market states were constructed by combining detailed data on various types of earned income. PCOS was identified through national inpatient and outpatient registers. Sociodemographic covariates (civil status, region of origin, highest attained education, number of children) were measured at the age of 29 years. Sequence analysis was used to identify clusters of typical labor market trajectories. Multinomial logistic regression was employed to assess the associations between being diagnosed with PCOS and belonging to the identified clusters. Results Women with PCOS spent less time in employment and were more dependent on sickness benefits during the follow-up time than those without PCOS. Five clusters of trajectories were identified: stable employment, education into employment, labor market exclusion, continuous unstable position, long-term sickness. Compared to being in stable employment cluster, women diagnosed with PCOS were 97% more likely to experience long-term sickness (RRR (relative risk ratio): 1.97 [CI: 1.90-2.05]), and had 11% higher risk of belonging to education into employment (RRR: 1.11 [CI: 1.07-1.15]) and a 4% higher risk (RRR: 1.04 [CI: 1.00-1.09]) of experiencing labor market exclusion. The magnitude of the association increased for education into employment and labor market exclusion after adjusting for covariates. Conclusions PCOS can lead to disadvantaged labor market outcomes and better strategies are needed in order to prevent economic exclusion among women diagnosed with the condition. Key messages • PCOS leads to disadvantaged labor market outcomes. • Women with PCOS may experience economic exclusion.

Conjugal ties may contribute to a convergence of health behaviours between migrants and natives, but the association between intermarriage and health outcomes remains understudied. We investigated mortality patterns among Finnish migrants in Sweden according to the spouse's country of birth and compared these patterns with those observed in the native populations of both Sweden and Finland. Leveraging register data from Sweden and Finland, we identified all married Finnish migrants aged 40-64 and their spouses in Sweden in 1999 and corresponding reference groups in both countries. We used a combination of direct matching and inverse probability weighting to adjust for sociodemographic differences between the groups. We followed individuals for all-cause, alcohol-related, smoking-related, and cardiovascular disease (CVD) mortality during 2000-17. Accounting for sociodemographic characteristics, Finnish migrant men married to Swedish-born as opposed to Finnish-born spouses showed lower all-cause [incidence rate ratio (IRR) 0.94, 95% confidence interval (CI) 0.90-0.98], and CVD mortality (IRR 0.88, 95% CI 0.81-0.95), levels more akin to native Swedes. Migrant women with Swedish-born spouses instead had higher smoking-related mortality (IRR 1.41, 95% CI 1.24-1.61) than those married to Finnish-born spouses, mirroring the higher smoking-related mortality of native Swedish women. Individual-level regression analysis on migrants further indicated lower alcohol-related mortality for intermarried men, adjusted for duration of marriage (IRR 0.74, 95% CI 0.56-0.98). These findings suggest that intermarriage with a native spouse can facilitate the convergence of health behaviours and behaviour-related mortality between migrants and natives.

Abstract Background Polycystic ovary syndrome (PCOS) has previously been associated with several comorbidities that may have shared genetic, epigenetic, developmental or environmental origins. PCOS may be influenced by prenatal androgen excess, poor intrauterine or childhood environmental factors, childhood obesity and learned health risk behaviors. We analyzed the association between PCOS and several relevant comorbidities while adjusting for early-life biological and socioeconomic conditions, also investigating the extent to which the association is affected by familial risk factors. Methods This total-population register-based cohort study included 333,999 full sisters, born between 1962 and 1980. PCOS and comorbidity diagnoses were measured at age 17-45 years through national hospital register data from 1997 to 2011, and complemented with information on the study subjects´ early-life and social characteristics. In the main analysis, sister fixed effects (FE) models were used to control for all time-invariant factors that are shared among sisters, thereby testing whether the association between PCOS and examined comorbidities is influenced by unobserved familial environmental, social or genetic factors. Results Three thousand five hundred seventy women in the Sister sample were diagnosed with PCOS, of whom 14% had obesity, 8% had depression, 7% had anxiety and 4% experienced sleeping, sexual and eating disorders (SSE). Having PCOS increased the odds of obesity nearly 6-fold (adjusted OR (aOR): 5.9 [95% CI:5.4-6.5]). This association was attenuated in models accounting for unobserved characteristics shared between full sisters, but remained considerable in size (Sister FE: aOR: 4.5 [95% CI: 3.6-5.6]). For depression (Sister FE: aOR: 1.4 [95% CI: 1.2-1.8]) and anxiety (Sister FE: aOR: 1.5 [95% CI: 1.2-1.8), there was a small decrease in the aORs when controlling for factors shared between sisters. Being diagnosed with SSE disorders yielded a 2.4 aOR (95% CI:2.0-2.6) when controlling for a comprehensive set of individual-level confounders, which only decreased slightly when controlling for factors at the family level such as shared genes or parenting style. Accounting for differences between sisters in observed early-life circumstances influenced the estimated associations marginally. Conclusion Having been diagnosed with PCOS is associated with a markedly increased risk of obesity and sleeping, sexual and eating disorders, also after accounting for factors shared between sisters and early-life conditions.

Abstract Background Residential segregation can be operationalized and measured in many ways, along distinct dimensions. There are multiple mechanisms through which segregation and health mutually affect each other. Consequently, contextual health effects of segregation may vary depending on how segregation is measured. Methods We used longitudinal Swedish register data to compare associations between local measures of residential segregation (migrant density, migrant isolation, and the mutual information index) and all-cause mortality among the adult migrant and native-born populations in Sweden’s three largest metropolitan regions between 2004-2016. Results Among migrants, modest positive mortality gradients were observed across measures of migrant density and isolation, where a higher level of segregation was associated with higher risks of all-cause mortality (Q5 RR ranged from 1.08-1.20 across cities and measures). However, these effects were largely attenuated by individual-level socioeconomic factors, and reversed when further controlling for neighborhood economic deprivation (Q5 RR ranged from 0.74-0.87). Among the native-born, a positive gradient for mortality was found (Q5 RR ranged from 1.31-1.45), although this was reduced when accounting for neighborhood deprivation (Q5 RR ranged from 1.01 -1.11). For both migrants and the native-born, the mutual information index showed no clear association with mortality, although a mortality advantage is observed for migrants in the most segregated areas after individual and neighborhood level adjustments (Q5 RR ranged from 0.73-0.86). Conclusions Our findings show that the manner in which residential segregation is conceptualized and operationalized alters associations with health. However, individual and other contextual level confounders are important determinants which influences the patterns. Much of the negative health effects of residential segregation can be perceived through the lack of economic opportunities. Key messages • Associations between segregation and all-cause mortality depends on how segregation is conceptualized and measured. • The mortality disadvantage observed in local areas with high migrant density may be attributed to the lack of economic opportunities in the neighborhood.

Background Ethnic minorities living in high-income countries have been disproportionately affected by COVID-19 in terms of infection rates and hospitalisations; however, less is known about long COVID in this population. Our aim was to examine the risk of long COVID and associated symptoms among ethnic minorities. Methods and Findings A Danish nationwide register-based cohort study of individuals diagnosed with COVID-19 aged [≥]18 years (n=2 334 271) between January 2020 and August 2022. We calculated the risk of long COVID diagnosis and long COVID symptoms among ethnic minorities compared with native Danes using multivariable Cox proportional hazard regression and logistic regression, respectively. Ethnic minorities from North Africa (adjusted hazard ratio [aHR] 1.41; 95% CI 1.12-1.79), Middle East (aHR 1.38; 95% CI 1.24-1.55), Eastern Europe (aHR 1.35; 95% CI 1.22-1.49), and Asia (aHR 1.23; 95% CI 1.09-1.40) had significantly greater risk of long COVID diagnosis than native Danes in both unadjusted and adjusted models. In the analysis by largest countries of origin, the greater risks of long COVID diagnosis were found in Iraqis (aHR 1.56; 95% CI 1.30- 1.88), Turks (aHR 1.42; 95% CI 1.24-1.63), and Somalis (aHR 1.42; 95% CI 1.07-1.91) after adjustment for confounders. Significant factor associated with an increased risk of long COVID diagnosis was COVID-19 hospitalisation. Furthermore, the odds of reporting cardiopulmonary symptoms (including dyspnoea, cough, and chest pain) and any long COVID symptoms were higher among North African, Middle Eastern, Eastern European, and Asian than among native Danes in both unadjusted and adjusted models. Conclusions Belonging to an ethnic minority group was significantly associated with an increased risk of long COVID indicating the need to better understand long COVID drivers and address care and treatment strategies in this population.

Abstract Background and aim A number of studies have found higher COVID-19 infection rates, hospitalizations and deaths in migrants and ethnic minorities throughout the Corona Pandemic. Some recent evidence also suggests higher risk of long COVID in migrants although less is known about the risk factors for long COVID in this population. The objective of our study is to examine the risk of long COVID in migrants and to examine whether preexisting health conditions, disease severity, social inequalities and vaccinations contribute to the association. Methods We used linked Swedish administrative registers to estimate the risk of a long COVID diagnosis in the population that had a confirmed COVID-19 infection. Poisson regressions were used to calculate incidence rate ratios between the Swedish born and migrant groups. Adjustments for preexisting health conditions, disease severity, vaccinations and social inequalities were separately introduced. Results Higher risks of long COVID were found among migrants from Africa, Asia, Eastern Europe, Finland, Middle-East and South America. While the contribution of vaccinations and social inequalities were modest, we found that disease severity (i.e. whether the person was hospitalized or treated in an intensive care unit) primarily contributed to the higher risk of long COVID found in migrants. Conclusions The greater exposure and impact of the COVID-19 virus among migrants during the pandemic also affected the longer-term consequences of infection in this at-risk population.

BackgroundEthnic minorities living in high-income countries have been disproportionately affected by Coronavirus Disease 2019 (COVID-19) in terms of infection rates, hospitalisations, and deaths; however, less is known about long COVID in these populations. Our aim was to examine the risk of long COVID and associated symptoms among ethnic minorities.Methods and findingsWe used nationwide register-based cohort data on individuals diagnosed with COVID-19 aged ≥18 years (n = 2,287,175) between January 2020 and August 2022 in Denmark. We calculated the risk of long COVID diagnosis and long COVID symptoms among ethnic minorities compared with native Danes using multivariable Cox proportional hazard regression and logistic regression, respectively. Among individuals who were first time diagnosed with COVID-19 during the study period, 39,876 (1.7%) were hospitalised and 2,247,299 (98.3%) were nonhospitalised individuals. Of the diagnosed COVID-19 cases, 1,952,021 (85.3%) were native Danes and 335,154 (14.7%) were ethnic minorities. After adjustment for age, sex, civil status, education, family income, and Charlson comorbidity index, ethnic minorities from North Africa (adjusted hazard ratio [aHR] 1.41, 95% confidence interval [CI] [1.12,1.79], p = 0.003), Middle East (aHR 1.38, 95% CI [1.24,1.55], p < 0.001), Eastern Europe (aHR 1.35, 95% CI [1.22,1.49], p < 0.001), and Asia (aHR 1.23, 95% CI [1.09,1.40], p = 0.001) had significantly greater risk of long COVID diagnosis than native Danes. In the analysis by largest countries of origin, the greater risks of long COVID diagnosis were found in people of Iraqi origin (aHR 1.56, 95% CI [1.30,1.88], p < 0.001), people of Turkish origin (aHR 1.42, 95% CI [1.24,1.63], p < 0.001), and people of Somali origin (aHR 1.42, 95% CI [1.07,1.91], p = 0.016). A significant factor associated with an increased risk of long COVID diagnosis was COVID-19 hospitalisation. The risk of long COVID diagnosis among ethnic minorities was more pronounced between January 2020 and June 2021. Furthermore, the odds of reporting cardiopulmonary symptoms (including dyspnoea, cough, and chest pain) and any long COVID symptoms were higher among people of North African, Middle Eastern, Eastern European, and Asian origins than among native Danes in both unadjusted and adjusted models. Despite including the nationwide sample of individuals diagnosed with COVID-19, the precision of our estimates on long COVID was limited to the sample of patients with symptoms who had contacted the hospital.ConclusionsBelonging to an ethnic minority group was significantly associated with an increased risk of long COVID, indicating the need to better understand long COVID drivers and address care and treatment strategies in these populations.

BACKGROUND:Socioeconomically vulnerable groups were overall more likely to develop severe Covid-19, but specific conditions in terms of preparedness, knowledge and the properties of the virus itself changed during the course of the pandemic. Inequalities in Covid-19 may therefore shift over time. This study examines the relationship between income and intensive care (ICU) episodes due to Covid-19 in Sweden during three distinct waves. METHODS:This study uses Swedish register data on the total adult population and estimates the relative risk (RR) of ICU episodes due to Covid-19 by income quartile for each month between March 2020 and May 2022, and for each wave, using Poisson regression analyses. RESULTS:The first wave had modest income-related inequalities, while the second wave had a clear income gradient, with the lowest income quartile having an increased risk compared to the high-income group [RR: 1.55 (1.36-1.77)]. In the third wave, the overall need for ICU decreased, but RRs increased, particularly in the lowest income quartile [RR: 3.72 (3.50-3.96)]. Inequalities in the third wave were partly explained by differential vaccination coverage by income quartile, although substantial inequalities remained after adjustment for vaccination status [RR: 2.39 (2.20-2.59)]. CONCLUSIONS:The study highlights the importance of considering the changing mechanisms that connect income and health during a novel pandemic. The finding that health inequalities increased as the aetiology of Covid-19 became better understood could be interpreted through the lens of adapted fundamental cause theory.

Abstract Background Finnish migrants in Sweden experience a mortality disadvantage relative to the native population in part due to health behaviours. Interaction between migrants and natives may lead to a convergence of health behaviours and thereby mortality between the groups. Finnish migrants who are married to a native Swede may thus have mortality rates that are more similar to the Swedish population compared to those married to fellow Finns. Conversely, mortality rates of migrants married to a fellow Finn may more closely resemble those of the population in Finland. Methods We use register data to identify all Finnish migrants aged 40-64 in Sweden in 1999 who were married to a native Swede or a fellow Finn. We identify reference groups in both Sweden and Finland, using a combination of inverse probability weighting and direct matching to adjust for differences in sociodemographic characteristics between the groups. We analyse mortality from all causes, CVD, alcohol and smoking related causes during 2000-2017. Results Compared to Finnish migrant men married to a fellow Finn, migrant men who are married to a native Swede have lower mortality rates, closer to that of the native population of Sweden. This difference is largely explained by sociodemographic characteristics, although lower levels of all-cause and CVD mortality remain after adjustment. By contrast, migrant women married to a native Swede have higher smoking-related mortality, closer to that of native Swedish women. Migrant women married to a fellow Finn have lower smoking-related mortality, closer to that of Finnish-born women in Finland. This pattern is especially pronounced when adjusting for sociodemographic characteristics. Conclusions Being married to a native is associated with lower all-cause and CVD mortality for migrant men and higher smoking-related mortality for migrant women. Depending on gender and risk factor intermarriage can be either protective or detrimental for migrant health. Key messages • The mortality risk of Finnish migrants in Sweden vary by spousal country of birth but if intermarriage is protective or detrimental for health depends on gender and risk factor. • Being married to a native Swede is associated with lower CVD mortality for Finnish migrant men and higher smoking-related mortality for Finnish migrant women.

Polycystic ovary syndrome (PCOS) is a medical condition with important consequences for women’s well-being and reproductive outcomes. Although the etiology of PCOS is not fully understood, there is increasing evidence of both genetic and environmental determinants, including development in early life. We studied a population of 977,637 singleton women born in in Sweden between 1973 and 1995, followed sometime between the age 15 and 40. The incidence of PCOS was measured using hospital register data during 2001–2012, complemented with information about the women’s, parents’ and sisters’ health and social characteristics from population and health care registers. Cox regression was used to study how PCOS is associated with intergenerational factors, and a range of early life characteristics. 11,594 women in the study sample were diagnosed with PCOS during the follow-up period. The hazard rate for PCOS was increased 3-fold (HR 2.98, 95% CI 2.43–3.64) if the index woman’s mother had been diagnosed with PCOS, and with 1.5-fold (HR 1.51, 95% CI 1.39–1.63) if their mother had diabetes mellitus. We found associations of PCOS with lower (<7) one-minute Apgar score (HR 1.19, 95% CI 1.09–1.29) and with post-term birth (HR 1.19, 95% CI 1.13–1.26). Furthermore, heavy (10+ cigarettes/day) maternal smoking (HR 1.30, 95% CI 1.18–1.44) and maternal obesity (HR 1.90, 95% CI 1.62–2.36) were strongly associated with PCOS. This study finds support for the heritability and fetal origins of PCOS. Risk of PCOS could be reduced by further emphasizing the importance of maternal and early life health.