SARS-CoV-2 vaccination uptake in six ethnic groups living in Amsterdam, the Netherlands: A registry-based study within the HELIUS cohort.

OBJECTIVE: Ethnic minority groups have experienced a disproportionate burden of COVID-19, and should therefore be especially encouraged to receive SARS-CoV-2 vaccination. This study compared first-dose uptake of the primary SARS-CoV-2 vaccination series across six ethnic groups in Amsterdam, the Netherlands in 2021. METHODS: We analyzed data from participants of the population-based HELIUS cohort. We linked their data to the SARS-CoV-2 vaccination registry data of the Public Health Service of Amsterdam. We included registry data from January 6, 2021 (the start of the Dutch vaccination campaign) until September 6, 2021 (a date by which all adults in the Netherlands could have received one or two vaccine doses). SARS-CoV-2 vaccination uptake was defined as having received at least one vaccine dose of the primary vaccination series. We examined the association between ethnicity and vaccination uptake using multivariable logistic regression, while accounting for the age and sex distribution of ethnic groups in Amsterdam. RESULTS: We included 19,006 participants (median age 53 years [interquartile range 41-62], 57% female). SARS-CoV-2 vaccination uptake was highest in the South-Asian Surinamese group (60.3%, 95%CI = 58.2-62.3%), followed by the Dutch (59.6%, 95%CI = 58.0-61.1%), Ghanaian (54.1%, 95%CI = 51.7-56.5%), Turkish (47.7%, 95%CI = 45.9-49.6%), African Surinamese (43.0%, 95%CI = 41.2-44.7%), and Moroccan (35.8%, 95%CI = 34.1-37.5%) groups. After adjusting for age, sex, perceived social support, and presence of relevant comorbidities, participants of African Surinamese, Ghanaian, Turkish and Moroccan origin were significantly less likely to be vaccinated than those of Dutch origin. CONCLUSIONS: Prevention strategies should continue tailoring to specific ethnic groups to encourage vaccination uptake and reduce barriers to vaccination.

Relative contributions of pre-pandemic factors and intra-pandemic activities to differential COVID-19 risk among migrant and non-migrant populations in the Netherlands: lessons for future pandemic preparedness.

BACKGROUND: Although risk factors for differences in SARS-CoV-2 infections between migrant and non-migrant populations in high income countries have been identified, their relative contributions to these SARS-CoV-2 infections, which could aid in the preparation for future viral pandemics, remain unknown. We investigated the relative contributions of pre-pandemic factors and intra-pandemic activities to differential SARS-CoV-2 infections in the Netherlands by migration background (Dutch, African Surinamese, South-Asian Surinamese, Ghanaians, Turkish, and Moroccan origin). METHODS: We utilized pre-pandemic (2011-2015) and intra-pandemic (2020-2021) data from the HELIUS cohort, linked to SARS-CoV-2 PCR test results from Public Health Service of Amsterdam (GGD Amsterdam). Pre-pandemic factors included socio-demographic, medical, and lifestyle factors. Intra-pandemic activities included COVID-19 risk aggravating and mitigating activities such as physical distancing, use of face masks, and other similar activities. We calculated prevalence ratios (PRs) in the HELIUS population that was merged with GGD Amsterdam PCR test data using robust Poisson regression (SARS-CoV-2 PCR test result as outcome, migration background as predictor). We then obtained the distribution of migrant and non-migrant populations in Amsterdam as of January 2021 from Statistics Netherlands. The migrant populations included people who have migrated themselves as well as their offspring. We used PRs and the population distributions to calculate population attributable fractions (PAFs) using the standard formula. We used age and sex adjusted models to introduce pre-pandemic factors and intra-pandemic activities, noting the relative changes in PAFs. RESULTS: From 20,359 eligible HELIUS participants, 8,595 were linked to GGD Amsterdam PCR test data and included in the study. Pre-pandemic socio-demographic factors (especially education, occupation, and household size) resulted in the largest changes in PAFs when introduced in age and sex adjusted models (up to 45%), followed by pre-pandemic lifestyle factors (up to 23%, especially alcohol consumption). Intra-pandemic activities resulted in the least changes in PAFs when introduced in age and sex adjusted models (up to 16%). CONCLUSION: Interventions that target pre-pandemic socio-economic status and other drivers of health inequalities between migrant and non-migrant populations are urgently needed at present to better prevent infection disparities in future viral pandemics.

Cardiovascular Risk Estimation Based on Country-of-Birth- and Country-of-Residence-Specific Scores among Migrants in the Netherlands: The HELIUS Study.

BACKGROUND: Regional and country-specific cardiovascular risk algorithms have been developed to improve CVD risk prediction. But it is unclear whether migrants' country-of-residence or country-of-birth algorithms agree in stratifying the CVD risk of these populations. We evaluated the risk stratification by the different algorithms, by comparing migrant country-of-residence-specific scores to migrant country-of-birth-specific scores for ethnic minority populations in the Netherlands. METHOD: data from the HELIUS study was used in estimating the CVD risk scores for participants using five laboratory-based (Framingham, Globorisk, Pool Cohort Equation II, SCORE II, and WHO II) and three nonlaboratory-based (Framingham, Globorisk, and WHO II) risk scores with the risk chart for the Netherlands. For the Globorisk, WHO II, and SCORE II risk scores, we also computed the risk scores using risk charts specified for the migrant home country. Risk categorization was first done according to the specification of the risk algorithm and then simplified to low (green), moderate (yellow and orange), and high risk (red). RESULTS: we observed differences in risk categorization for different risk algorithms ranging from 0% (Globorisk) to 13% (Framingham) for the high-risk category, as well as differences in the country-of-residence- and country-of-birth-specific scores. Agreement between different scores ranged from none to moderate. We observed a moderate agreement between the Netherlands-specific SCORE II and the country-of-birth SCORE II for the Turkish and a nonagreement for the Dutch Moroccan population. CONCLUSION: disparities exist in the use of the country-of-residence-specific, as compared to the country-of-birth, risk algorithms among ethnic minorities living in the Netherlands. Hence, there is a need for further validation of country-of-residence- and country-of-birth-adjusted scores to ascertain appropriateness and reliability.

Associations of psychosocial stress with type 2 diabetes and glycaemic control among Ghanaians: The RODAM study.

BACKGROUND: The extent to which psychosocial stress relates to type 2 diabetes among sub-Saharan Africans is not well understood. We assessed associations of psychosocial stresses with type 2 diabetes status and glycaemic control among Ghanaians. METHODS: We used data from Research on Obesity and Diabetes among African Migrants (RODAM) study. We performed logistic and linear regression models to assess association of psychosocial stresses with type 2 diabetes and HbA1c respectively with adjustments for age, sex, education and other stresses. We also assessed moderation effects of migration status (migrant Ghanaians vs. non-migrant Ghanaians), age, sex and education by adding interaction terms in models. RESULTS: Four thousand eight hundred and forty one Ghanaians were included with 44% resident in Ghana, 62% women, mean age of 46 years and 10% having type 2 diabetes. Psychosocial stress at home and at work were not associated with type 2 diabetes or HbA1c levels. Negative life events in past 12 months were negatively associated with type 2 diabetes (adjusted odds ratio = 0.93, 95% CI 0.87-0.99). Perceived discrimination was positively associated with type 2 diabetes (aOR = 1.01, 95% CI 1.004-1.03). Both associations were more pronounced in men. Perceived discrimination was also positively associated with HbA1c levels, especially among those with type 2 diabetes (adjusted ß = 0.01, 95% CI 0.007-0.02). CONCLUSIONS: Perceived discrimination and negative life events are associated with type 2 diabetes and glycaemic control among Ghanaians, especially in men. Further studies are needed to identify context-specific mechanisms underlying these associations.

Inequalities in COVID-19 deaths by migration background during the first wave, interwave period and second wave of the COVID-19 pandemic: a closed cohort study of 17 million inhabitants of the Netherlands.

BACKGROUND: It is not known how differences in COVID-19 deaths by migration background in the Netherlands evolved throughout the pandemic, especially after introduction of COVID-19 prevention measures targeted at populations with a migration background (in the second wave). We investigated associations between migration background and COVID-19 deaths across first wave of the pandemic, interwave period and second wave in the Netherlands. METHODS: We obtained multiple registry data from Statistics Netherlands spanning from 1 March 2020 to 14 March 2021 comprising 17.4 million inhabitants. We estimated incidence rate ratios for COVID-19 deaths by migration background using Poisson regression models and adjusted for relevant sociodemographic factors. RESULTS: Populations with a migration background, especially those with Turkish, Moroccan and Surinamese background, exhibited higher risk of COVID-19 deaths than the Dutch origin population throughout the study periods. The elevated risk of COVID-19 deaths among populations with a migration background (as compared with Dutch origin population) was around 30% higher in the second wave than in the first wave. CONCLUSIONS: Differences in COVID-19 deaths by migration background persisted in the second wave despite introduction of COVID-19 prevention measures targeted at populations with a migration background in the second wave. Research on explanatory mechanisms and novel prevention measures are needed to address the ongoing differences in COVID-19 deaths by migration background.

An epigenome-wide association study of insulin resistance in African Americans.

BACKGROUND: African Americans have a high risk for type 2 diabetes (T2D) and insulin resistance. Studies among other population groups have identified DNA methylation loci associated with insulin resistance, but data in African Americans are lacking. Using DNA methylation profiles of blood samples obtained from the Illumina Infinium® HumanMethylation450 BeadChip, we performed an epigenome-wide association study to identify DNA methylation loci associated with insulin resistance among 136 non-diabetic, unrelated African American men (mean age 41.6 years) from the Howard University Family Study. RESULTS: We identified three differentially methylated positions (DMPs) for homeostatic model assessment of insulin resistance (HOMA-IR) at 5% FDR. One DMP (cg14013695, HOXA5) is a known locus among Mexican Americans, while the other two DMPs are novel-cg00456326 (OSR1; beta = 0.027) and cg20259981 (ST18; beta = 0.010). Although the cg00456326 DMP is novel, the OSR1 gene has previously been found associated with both insulin resistance and T2D in Europeans. The genes HOXA5 and ST18 have been implicated in biological processes relevant to insulin resistance. Differential methylation at the significant HOXA5 and OSR1 DMPs is associated with differences in gene expression in the iMETHYL database. Analysis of differentially methylated regions (DMRs) did not identify any epigenome-wide DMRs for HOMA-IR. We tested transferability of HOMA-IR associated DMPs from five previous EWAS in Mexican Americans, Indian Asians, Europeans, and European ancestry Americans. Out of the 730 previously reported HOMA-IR DMPs, 47 (6.4%) were associated with HOMA-IR in this cohort of African Americans. CONCLUSIONS: The findings from our study suggest substantial differences in DNA methylation patterns associated with insulin resistance across populations. Two of the DMPs we identified in African Americans have not been reported in other populations, and we found low transferability of HOMA-IR DMPs reported in other populations in African Americans. More work in African-ancestry populations is needed to confirm our findings as well as functional analyses to understand how such DNA methylation alterations contribute to T2D pathology.

COVID-19 Impacts Across Multiple Life Domains of Vulnerable Socio-Demographic Groups Including Migrants: A Descriptive Cross-Sectional Study.

Objectives: We assessed the impacts of COVID-19 on multiple life domains across socio-demographic groups in Netherlands. Methods: After the first COVID-19 wave, we distributed online questionnaires among 13,031 participants of the multi-ethnic HELIUS cohort. Questionnaires contained questions on changes in income status, healthy behaviors, mental health, and access to non-COVID-19 health care. We then calculated differences in adjusted proportions of participants that reported negative changes across multiple life domains by migration background, age, sex, education, and occupation. Results: 4,450 individuals (35%) responded, of which 4,294 were included. Older populations and men seemed to be less vulnerable to negative changes in multiple life domains during the COVID-19 pandemic as compared to the pre-pandemic period, while populations with a migration background and lower education/occupation groups seemed to be more vulnerable to negative changes. Conclusion: Not all populations vulnerable to SARS-CoV-2 infection and mortality are also more vulnerable to COVID-19 impacts across multiple other life domains. Targeted interventions are needed in socio-demographic groups that are most impacted by COVID-19 in various life domains to prevent a further increase of their already increased risk of chronic diseases after the pandemic.

The Magnitude and Directions of the Associations between Early Life Factors and Metabolic Syndrome Differ across Geographical Locations among Migrant and Non-Migrant Ghanaians-The RODAM Study.

BACKGROUND: Early-life factors (ELFs) such as childhood nutrition and childhood socio-economic status could be the drivers of the increase in metabolic syndrome (MetSyn) among African populations, but data are lacking. This study evaluated whether markers of childhood nutritional status and childhood socio-economic status were associated with MetSyn in adulthood among migrant Ghanaians living in Europe and non-migrant Ghanaians living in Ghana. METHODS: Data from the Research on Obesity and Diabetes among African Migrants (RODAM) study, involving 2008 migrants and 2320 non-migrants aged ≥25 years, were analysed for this study. We used leg-length to height ratio (LHR), which is an anthropometric marker of childhood nutritional status, and parental education, which is a marker of childhood socio-economic status, as proxies. Adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) were calculated by logistic regression with adjustments for demographic and lifestyle factors. RESULTS: Parental education was higher among Ghanaians in Europe than among residents in rural and urban Ghana. The prevalence of MetSyn was 18.5%, 27.7% and 33.5% for rural, urban, and migrant residents, respectively. LHR was inversely associated with MetSyn among migrants. Compared with high paternal education, individuals with low paternal education had lower odds of MetSyn in migrants (AOR 0.71 95% CI 0.54-0.94). In contrast, compared with high maternal education, individuals with intermediate maternal education had higher odds of MetSyn in urban Ghanaians (AOR 4.53 95% CI 1.50-3.74). No associations were found among rural Ghanaians. CONCLUSION: The magnitude and direction of the associations between ELFs and MetSyn differ across geographical locations. Intermediate maternal education was positively associated with MetSyn among urban Ghanaians, while LHR and low paternal education were inversely associated with MetSyn among migrant Ghanaians. Further research into the interplay of genetics, environment and behaviour is needed to elucidate the underlying pathological mechanisms of MetSyn amongst migrants.

Genome-wide DNA methylation analysis on C-reactive protein among Ghanaians suggests molecular links to the emerging risk of cardiovascular diseases.

Molecular mechanisms at the intersection of inflammation and cardiovascular diseases (CVD) among Africans are still unknown. We performed an epigenome-wide association study to identify loci associated with serum C-reactive protein (marker of inflammation) among Ghanaians and further assessed whether differentially methylated positions (DMPs) were linked to CVD in previous reports, or to estimated CVD risk in the same population. We used the Illumina Infinium® HumanMethylation450 BeadChip to obtain DNAm profiles of blood samples in 589 Ghanaians from the RODAM study (without acute infections, not taking anti-inflammatory medications, CRP levels < 40 mg/L). We then used linear models to identify DMPs associated with CRP concentrations. Post-hoc, we evaluated associations of identified DMPs with elevated CVD risk estimated via ASCVD risk score. We also performed subset analyses at CRP levels ≤10 mg/L and replication analyses on candidate probes. Finally, we assessed for biological relevance of our findings in public databases. We subsequently identified 14 novel DMPs associated with CRP. In post-hoc evaluations, we found that DMPs in PC, BTG4 and PADI1 showed trends of associations with estimated CVD risk, we identified a separate DMP in MORC2 that was associated with CRP levels ≤10 mg/L, and we successfully replicated 65 (24%) of previously reported DMPs. All DMPs with gene annotations (13) were biologically linked to inflammation or CVD traits. We have identified epigenetic loci that may play a role in the intersection between inflammation and CVD among Ghanaians. Further studies among other Africans are needed to confirm our findings.

DNA methylation as the link between migration and the major noncommunicable diseases: the RODAM study.

Aim: We assessed epigenome-wide DNA methylation (DNAm) differences between migrant and non-migrant Ghanaians. Materials & methods: We used the Illumina Infinium® HumanMethylation450 BeadChip to profile DNAm of 712 Ghanaians in whole blood. We used linear models to detect differentially methylated positions (DMPs) associated with migration. We performed multiple post hoc analyses to validate our findings. Results: We identified 13 DMPs associated with migration (delta-beta values: 0.2-4.5%). Seven DMPs in CPLX2, EIF4E3, MEF2D, TLX3, ST8SIA1, ANG and CHRM3 were independent of extrinsic genomic influences in public databases. Two DMPs in NLRC5 were associated with duration of stay in Europe among migrants. All DMPs were biologically linked to migration-related factors. Conclusion: Our findings provide the first insights into DNAm differences between migrants and non-migrants.

Epigenetic age acceleration in the emerging burden of cardiometabolic diseases among migrant and non-migrant African populations: the population based cross-sectional RODAM study.

BACKGROUND: African populations are experiencing health transitions due to rapid urbanization and international migration. However, the role of biological aging in this emerging burden of cardiometabolic diseases (CMD) among migrant and non-migrant Africans is unknown. We aimed to examine differences in epigenetic age acceleration (EAA) as measured by four clocks (Horvath, Hannum, PhenoAge and GrimAge) and their associations with cardiometabolic factors among migrant Ghanaians in Europe and non-migrant Ghanaians. METHODS: Genome-wide DNA methylation (DNAm) data of 712 Ghanaians from cross-sectional RODAM study were used to quantify EAA. We assessed correlation of DNAmAge measures with chronological age, and then performed linear regressions to determine associations of body mass index (BMI), fasting blood glucose (FBG), blood pressure, alcohol consumption, smoking, physical activity, and one-carbon metabolism nutrients with EAA among migrant and non-migrants. We replicated our findings among 172 rural-urban sibling pairs from India migration study and among 120 native South Africans from PURE-SA-NW study. FINDINGS: We found that Ghanaian migrants have lower EAA than non-migrants. Within migrants, higher FBG was positively associated with EAA measures. Within non-migrants, higher BMI, and Vitamin B9 (folate) intake were negatively associated with EAA measures. Our findings on FBG, BMI and folate were replicated in the independent cohorts. INTERPRETATION: Our study shows that migration is negatively associated with EAA among Ghanaians. Moreover, cardiometabolic factors are differentially associated with EAA within migrant and non-migrant subgroups. Our results call for context-based interventions for CMD among transitioning populations that account for effects of biological aging. FUNDING: European Commission.

Epigenome-wide association study for perceived discrimination among sub-Saharan African migrants in Europe - the RODAM study.

Sub-Saharan African (SSA) migrants in Europe experience psychosocial stressors, such as perceived discrimination (PD). The effect of such a stressor on health could potentially be mediated via epigenetics. In this study we performed an epigenome-wide association study (EWAS) to assess the association between levels of PD with genome-wide DNA methylation profiles in SSA migrants. The Illumina 450 K DNA-methylation array was used on whole blood samples of 340 Ghanaian adults residing in three European cities from the cross-sectional Research on Obesity and Diabetes among African Migrants (RODAM) study. PD was assessed using sum scores of the Everyday Discrimination Scale (EDS). Differentially methylated positions and regions (DMPs and DMRs) were identified through linear regression analysis. Two hypo-methylated DMPs, namely cg13986138 (CYFIP1) and cg10316525(ANKRD63), were found to be associated with PD. DMR analysis identified 47 regions associated with the PD. To the best of our knowledge, this survey is the first EWAS for PD in first generation SSA migrants. We identified two DMPs associated with PD. Whether these associations underlie a consequence or causal effect within the scope of biological functionality needs additional research.

Hyperuricaemia and its association with 10-year risk of cardiovascular disease among migrant and non-migrant African populations: the RODAM study.

OBJECTIVE: In the advent of rapid urbanisation, migration and epidemiological transition, the extent to which serum uric acid (sUA) affects cardiovascular disease (CVD) risk among Africans is not well understood. We assessed differences in sUA levels and associations with CVD risk among migrant Ghanaians in Europe and non-migrant Ghanaians in rural and urban Ghana. METHODS: Baseline data from 633 rural, 916 urban and 2315 migrant participants (40-70 years) from the cross-sectional RODAM study were analysed. Hyperuricaemia was defined as sUA >7 mg/dl in men and >6 mg/dl in women. The 10-year risk of atherosclerotic cardiovascular disease (ASCVD) was calculated using the American College of Cardiology (ACC)/American Heart Association (AHA) risk score which takes into account ethnic minority populations. High CVD risk was defined as ASCVD risk scores ≥7.5%. Logistic regressions were used to assess associations between hyperuricaemia and CVD risk. RESULTS: Prevalence for hyperuricaemia in rural, urban and migrant participants was 17.4%, 19.1% and 31.7% for men, and 15.9%, 18.2% and 33.2% for women, respectively. Hyperuricaemia was positively associated with elevated CVD risk among rural residents (adjusted OR for men 3.28, 95% CI: 1.21-8.96, 6.36, 95% CI: 2.98-13.56 for women), urban residents (1.12, 95% CI: 0.45-2.81 for men, 2.11, 95% CI: 1.26-3.52 for women) and migrants (1.73, 95% CI: 1.01-2.96 for men, 4.61, 95% CI: 3.05-6.97 for women). CONCLUSION: Our study shows variations of sUA levels in different African contexts. Hyperuricaemia is associated with elevated 10-year CVD risk in both migrants and non-migrants. Further studies should identify factors driving associations between sUA and CVD risk in Africans.

OBJECTIF: Avec l'avènement de l'urbanisation rapide, de la migration et de la transition épidémiologique, la mesure dans laquelle l'acide urique sérique (AUs) affecte le risque de maladie cardiovasculaire (MCV) chez les Africains n'est pas bien comprise. Nous avons évalué les différences dans les niveaux d'AUs et les associations avec le risque de MCV chez les ghanéens migrants en Europe et non migrants dans les zones rurales et urbaines du Ghana. MÉTHODES: Les données de base de 633 participants ruraux, 916 urbains et 2.315 migrants, de 40 à 70 ans de l'étude transversale RODAM ont été analysées. L'hyperuricémie a été définie comme une AUs > 7 mg/dl chez les hommes et >6 mg/dl chez les femmes. Le risque sur 10 ans de MCV athérosclérosique (MCVAS) a été calculé en utilisant le score de risque de l'American College of Cardiology (ACC)/American Heart Association (AHA) qui prend en compte les populations des minorités ethniques. Un risque de MCV élevé était défini comme un score de risque MCVAS ≥7,5%. Des régressions logistiques ont été utilisées pour évaluer les associations entre l'hyperuricémie et le risque de MCV. RÉSULTATS: La prévalence de l'hyperuricémie chez les participants ruraux, urbains et migrants était de 17,4% ; 19,1% et 31,7% pour les hommes et 15,9%, 18,2% et 33,2% pour les femmes, respectivement. L'hyperuricémie était positivement associée à un risque élevé de MCV chez les résidents ruraux (OR ajusté 3,28 ; IC95%: 1,21-8,96 pour les hommes, 6,36, IC95%: 2,98-13,56 pour les femmes), les résidents urbains (1,12 ; IC95%: 0,45-2,81 pour les hommes, 2,11 ; IC95%: 1,26-3,52 pour les femmes) et les migrants (1,73 ; IC95%: 1,01-2,96 pour les hommes, 4,61 ; IC95%: 3,05-6,97 pour les femmes). CONCLUSION: Notre étude montre des variations des niveaux d'AUs dans différents contextes africains. L'hyperuricémie est associée à un risque élevé de MCV sur 10 ans chez les migrants et les non-migrants. Des études plus poussées devraient identifier les facteurs à l'origine des associations entre le risque d'AUs et de MCV chez les africains.

Prevalence and determinants of type 2 diabetes among lean African migrants and non-migrants: the RODAM study.

BACKGROUND: Exposure to adverse conditions earlier in life-course can predispose to type 2 diabetes in adulthood, irrespective of body mass index (BMI). However, the burden of type 2 diabetes in lean Africans is not well understood despite higher exposure to adverse early life conditions. Mirroring ongoing epidemiological transition, we assessed the burden and determinants of type 2 diabetes in a homogenous group of lean Ghanaians residing in rural and urban Ghana, and as migrants in Europe. METHODS: Baseline data from 2179 RODAM study participants with BMI<25kg/m2 (25-70 years) were analyzed. Prevalence and determinants of type 2 diabetes were estimated using logistic regression analysis. Adjustments were made for socio-demographic and lifestyle factors, use of anti-diabetic medication and optimal blood glucose control. RESULTS: Prevalence of type 2 diabetes in rural, urban and migrant lean participants were 3.5%, 8.9% and 7.5% respectively, representing 55.4%, 35.6%, 13.2% of all participants with type 2 diabetes. Compared with lean rural participants, the odds of type 2 diabetes were higher in lean urban participants (adjusted OR = 8.81, 95% CI = 6.56-11.06), followed by migrants (5.27, 95% CI = 3.51-6.91). Irrespective of site, determinants of type 2 diabetes in lean participants include; presence of hypertension, physical inactivity, hypercholesterolemia and age (>45 years). CONCLUSIONS: Our study shows a high prevalence of type 2 diabetes among lean African populations in different geographical settings. Future studies are needed in-order to examine how contextual differences are related to the pathophysiology of type 2 diabetes in lean individuals.

Investigating associations between rural-to-urban migration and cardiometabolic disease in Malawi: a population-level study.

BACKGROUND: The extent to which rural-to-urban migration affects risk for cardiometabolic diseases (CMD) in Africa is not well understood. We investigated prevalence and risk for obesity, diabetes, hypertension and precursor conditions by migration status. METHODS: In a cross-sectional survey in Malawi (February 2013-March 2017), 13 903 rural, 9929 rural-to-urban migrant and 6741 urban residents (≥18 years old) participated. We interviewed participants, measured blood pressure and collected anthropometric data and fasting blood samples to estimate population prevalences and odds ratios, using negative binomial regression, for CMD, by migration status. In a sub-cohort of 131 rural-urban siblings-sets, migration-associated CMD risk was explored using conditional Poisson regression. RESULTS: In rural, rural-to-urban migrant and urban residents, prevalence estimates were; 8.9, 20.9 and 15.2% in men and 25.4, 43.9 and 39.3% in women for overweight/obesity; 1.4, 2.9 and 1.9% in men and 1.5, 2.8 and 1.7% in women for diabetes; and 13.4, 18.8 and 12.2% in men and 13.7, 15.8 and 10.2% in women for hypertension. Rural-to-urban migrants had the greatest risk for hypertension (adjusted relative risk for men 1.18; 95% confidence interval 1.04-1.34 and women 1.17: 95% confidence interval 1.05-1.29) and were the most screened, diagnosed and treated for CMD, compared with urban residents. Within sibling sets, rural-to-urban migrant siblings had a higher risk for overweight and pre-hypertension, with no evidence for differences by duration of stay. CONCLUSIONS: Rural-to-urban migration is associated with increased CMD risk in Malawi. In a poor country experiencing rapid urbanization, interventions for the prevention and management of CMD, which reach migrant populations, are needed.

Perceived discrimination and stressful life events are associated with cardiovascular risk score in migrant and non-migrant populations: The RODAM study.

BACKGROUND: Psychosocial stress could be an underlying factor for emerging risk of cardiovascular diseases (CVD) in Africans. We assessed the association between psychosocial stress and estimated CVD risk among non-migrant Ghanaians and migrant Ghanaians living in Europe. METHODS: Data from the Research on Obesity and Diabetes among African Migrants (RODAM) study, involving 2315 migrant and 1549 non-migrants aged 40-70 years were used for this study. Psychosocial stress included self-reported stress at work and home, recent negative life events and perceived discrimination. CVD risk was estimated using the pooled cohort equations with estimates ≥7.5% over 10 years defining high CVD risk. Adjusted Odds Ratios (AOR) and 95% confidence intervals (95% CI) were calculated by logistic regression with adjustments for socioeconomic status. RESULTS: Prevalence for migrant and non-migrants were; 72.5% and 84.9% for psychosocial stress and 35.9% and 27.4% for high estimated CVD risk. Stress at work and home was not associated with a high estimated CVD risk in either group. Recent negative life events were associated with a high estimated CVD risk in non-migrants only (AOR 1.29, 95%CI 1.02-1.68, p = 0.048). Higher levels of perceived discrimination were associated with a high estimated CVD risk in migrants only (AOR 2.74, 95%CI 1.95-3.86, p < 0.001). CONCLUSIONS: Among migrant populations, higher levels of perceived discrimination were associated with a high estimated CVD risk, and this was also true for recent negative life events among non-migrant populations. Further research is needed to identify context specific mechanisms that underlie associations between psychological characteristics and CVD risk.