The effect of age at migration on cardiovascular mortality among elderly Mexican immigrants

Africans Who Arrive in the United States before 20 Years of Age Maintain Both Cardiometabolic Health and Cultural Identity: Insight from the Africans in America Study

The overall consensus is that foreign-born adults who come to America age < 20 y achieve economic success but develop adverse behaviors (smoking and drinking) that lead to worse cardiometabolic health than immigrants who arrive age ≥ 20 y. Whether age of immigration affects the health of African-born Blacks living in America is unknown. Our goals were to examine cultural identity, behavior, and socioeconomic factors and determine if differences exist in the cardiometabolic health of Africans who immigrated to America before and after age 20 y. Of the 482 enrollees (age: 38 ± 1 (mean ± SE), range: 20–65 y) in the Africans in America cohort, 23% (111/482) arrived age < 20 y, and 77% (371/482) arrived age ≥ 20 y. Independent of francophone status or African region of origin, Africans who immigrated age < 20 y had similar or better cardiometabolic health than Africans who immigrated age ≥ 20 y. The majority of Africans who immigrated age < 20 y identified as African, had African-born spouses, exercised, did not adopt adverse health behaviors, and actualized early life migration advantages, such as an American university education. Due to maintenance of cultural identity and actualization of opportunities in America, cardiometabolic health may be protected in Africans who immigrate before age 20. In short, immigrant health research must be cognizant of the diversity within the foreign-born community and age of immigration.

Gender and Age of Migration Differences in Mortality Among Older Mexican Americans

OBJECTIVES

Using a gendered life course perspective, we examine whether the relationship between age of migration and mortality is moderated by gender among a cohort of older Mexican Americans.

METHODS

Data from the Hispanic Established Populations for the Epidemiological Study of the Elderly and recently matched mortality data are used to estimate Cox proportional hazard models.

RESULTS

Our findings indicate that the relationship between age of migration and mortality is moderated by gender, suggesting a more nuanced perspective of the immigrant mortality paradox. Among men, midlife migrants exhibit an 18% lower risk of mortality compared to their U.S.-born co-ethnics, possibly due to immigrant selectivity at the time of migration. Conversely, late-life migrant women exhibit a 17% lower risk of mortality relative to U.S.-born women, attributed in part to socio-cultural characteristics that influence lifestyle risk factors across the life course.

DISCUSSION

Selection mechanisms and acculturation processes associated with the immigrant experience are contingent on both age and gender, suggesting the utility of an integrated life course approach to contextualize the mortality profiles of older immigrants. These findings demonstrate the heterogeneity among immigrants and highlight the need to understand gender differences in the migration process when assessing the immigrant mortality paradox.

Heterogeneous Exposure Associations in Observational Cohort Studies: The Example of Blood Pressure in Older Adults

Heterogeneous exposure associations (HEAs) can be defined as differences in the association of an exposure with an outcome among subgroups that differ by a set of characteristics. In this article, we intend to foster discussion of HEAs in the epidemiologic literature and present a variant of the random forest algorithm that can be used to identify HEAs. We demonstrate the use of this algorithm in the setting of the association between systolic blood pressure and death in older adults. The training set included pooled data from the baseline examination of the Cardiovascular Health Study (1989-1993), the Health, Aging, and Body Composition Study (1997-1998), and the Sacramento Area Latino Study on Aging (1998-1999). The test set included data from the National Health and Nutrition Examination Survey (1999-2002). The hazard ratios ranged from 1.25 (95% confidence interval: 1.13, 1.37) per 10-mm Hg increase in systolic blood pressure among men aged ≤67 years with diastolic blood pressure greater than 80 mm Hg to 1.00 (95% confidence interval: 0.96, 1.03) among women with creatinine concentration ≤0.7 mg/dL and a history of hypertension. HEAs have the potential to improve our understanding of disease mechanisms in diverse populations and guide the design of randomized controlled trials to control exposures in heterogeneous populations.

"Men like to Eat More Rice and Beans and Things like That": The Influence of Childhood Experience and Life Course Events on Dietary Acculturation

Life course perspective provides a framework for examining the immigrant experience within the context of globalization and transnationalism. Life course perspective states that individuals develop food choice trajectories based on childhood experiences with food. This study examined the influence of childhood experiences and life events on eating behaviors of Dominican born women in Santo Domingo, Dominican Republic, and New York City. Findings revealed that women developed traditional or non-traditional food choice trajectories. These food choice trajectories remained stable through transition points, such as immigration, marriage, and divorce. Women discussed changes in the amount of food that was eaten, which may explain weight gain after immigration. These findings highlight the limitations of acculturation theory in understanding the eating behaviors of immigrants and provide an alternative explanation for weight gain after immigration.

Physical Functioning and Disability Trajectories by Age of Migration Among Mexican Elders in the United States

Objectives

To address a gap in our understanding of the long-term consequences of nativity and age of migration for the health of the Mexican elderly population.

Method

We employ age graded latent growth curve models stratified by gender to examine the extent of physical functioning and disability, measured in terms of performance-oriented mobility assessments (POMAs) and activities of daily living (ADLs) after age 65 in a large longitudinal sample of Mexican-origin individuals.

Results

Self-care measured ADLs show no age of migration differences. However, physical capacity measured POMAs differ significantly for men and women by age of migration. Migrants who arrived in midlife have fewer functional limitations at age 65 but have steeper increase in POMAs with age.

Discussion

With a rapidly changing demographic profile that includes a large number of aging Mexican-origin immigrants, our society must implement social and health policies to ameliorate the negative health outcomes among immigrant and U.S.-born minority groups.

Physical Functioning and Disability Trajectories by Age of Migration Among Mexican Elders in the United States

Objectives

To address a gap in our understanding of the long-term consequences of nativity and age of migration for the health of the Mexican elderly population.

Method

We employ age graded latent growth curve models stratified by gender to examine the extent of physical functioning and disability, measured in terms of performance-oriented mobility assessments (POMAs) and activities of daily living (ADLs) after age 65 in a large longitudinal sample of Mexican-origin individuals.

Results

Self-care measured ADLs show no age of migration differences. However, physical capacity measured POMAs differ significantly for men and women by age of migration. Migrants who arrived in midlife have fewer functional limitations at age 65 but have steeper increase in POMAs with age.

Discussion

With a rapidly changing demographic profile that includes a large number of aging Mexican-origin immigrants, our society must implement social and health policies to ameliorate the negative health outcomes among immigrant and U.S.-born minority groups.

Association of Acculturation and Health Literacy with Prevalent Dysglycemia and Diabetes Control Among Latinos in the Boston Area Community Health (BACH) Survey

This study assessed the effect of acculturation on type 2 diabetes and whether health literacy may mediate this association. The Boston Area Community Health cohort is a multi-stage stratified random sample of adults from Boston including 744 Latinos. We defined dysglycemia as a HbA1c ≥5.7 %. Multivariable analyses examined the associations between acculturation and health literacy adjusting for demographic and clinical variables. Similar analyses were performed among participants with HbA1c ≥7.0 % to assess the association between acculturation and diabetes control. Among an insured primarily foreign born Spanish speaking Latino population, with a long residence period in the US and good healthcare utilization, higher levels of acculturation were not associated with dysglycemia. Lower levels of acculturation were associated with worse diabetes control. Health literacy level did not modify these associations. Elucidating the components of heterogeneity among Latinos will be essential for understanding the influence of acculturation on diabetes.

Age of Migration Life Expectancy with Functional Limitations and Morbidity in Mexican Americans

The U.S. Mexican American population enjoys longer life expectancies relative to other racial/ethnic groups but is disproportionately affected by chronic conditions and functional limitations. Studying the impact of heterogeneity in age, time and other characteristics of migration among older Mexican Americans can inform our understanding of health disparities and healthcare needs in later-life. This research used 20 years of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to assess the proportion of life spent with functional limitations and one or more morbidity (according to age of migration and sex) in the U.S. Mexican-American population. The results indicate that early-life and late-life migrant women spend more years with Performance-Oriented Mobility Assessment limitations than U.S.-born women. Conversely, midlife migrant women were not statistically different from U.S.-born women in years spent disabled. In men, midlife migrants had longer life expectancies and had more disability-free years than U.S.-born men. For morbidity, late-life migrant women spent a significantly smaller proportion of their elderly years with morbidity than U.S.-born women, but late-life migrant men spent more years with morbidity than U.S.-born men. These findings illustrate that older Mexican Americans in the United States are heterogeneous in nativity and health outcomes. More years spent disabled or unhealthy may result in greater burden on family members and greater dependence on public resources. These findings have implications for the development of social and health policies to appropriately target the medical conditions and disabilities of older Mexican Americans entering late life.

Health Risk Behaviors by Length of Time in the United States Among High School Students in Five Sites

One in five public school students is from an immigrant-headed household. We used Youth Risk Behavior Survey data from one state and four large urban school districts to examine whether length of time living in the US was associated with health risk behaviors. Logistic regression models, using weighted data, controlled for sex, race/ethnicity, and grade. Compared to US natives, not having always lived in the US was correlated with lower risk for some behaviors (e.g., current marijuana use and alcohol use) among high school students, but higher risk for other behaviors (e.g., attempted suicide, physical inactivity). Many findings were inconsistent across the study sites. Interventions that specifically target recently-arrived school-aged youth to prevent behaviors that put health and safety at risk, may result in the best outcomes for immigrant youth. Care should be taken to understand the specific health risks present in different immigrant communities.

Explaining the Immigrant Health Advantage: Self-selection and Protection in Health-Related Factors Among Five Major National-Origin Immigrant Groups in the United States

Despite being newcomers, immigrants often exhibit better health relative to native-born populations in industrialized societies. We extend prior efforts to identify whether self-selection and/or protection explain this advantage. We examine migrant height and smoking levels just prior to immigration to test for self-selection; and we analyze smoking behavior since immigration, controlling for self-selection, to assess protection. We study individuals aged 20-49 from five major national origins: India, China, the Philippines, Mexico, and the Dominican Republic. To assess self-selection, we compare migrants, interviewed in the National Health and Interview Surveys (NHIS), with nonmigrant peers in sending nations, interviewed in the World Health Surveys. To test for protection, we contrast migrants' changes in smoking since immigration with two counterfactuals: (1) rates that immigrants would have exhibited had they adopted the behavior of U.S.-born non-Hispanic whites in the NHIS (full "assimilation"); and (2) rates that migrants would have had if they had adopted the rates of nonmigrants in sending countries (no-migration scenario). We find statistically significant and substantial self-selection, particularly among men from both higher-skilled (Indians and Filipinos in height, Chinese in smoking) and lower-skilled (Mexican) undocumented pools. We also find significant and substantial protection in smoking among immigrant groups with stronger relative social capital (Mexicans and Dominicans).

Substance use, age at migration, and length of residence among adult immigrants in the United States

In this study we scrutinize prevalence of current smoking and binge drinking among adult US immigrants, and examine whether age at migration predicts these two behaviors and moderates the effect of length of residence. Immigrant groups include those from Latin America/Caribbean, East and South Asia, Sub-Saharan Africa, Europe/Central Asia, and Middle East/North Africa. Multivariate logistic regressions are estimated using cross-sectional data from the New Immigrant Survey (N = 7,397). Results show that patterns of smoking and binge drinking vary by gender and by region of origins. In addition, arriving at age 0-9 are directly associated with higher odds of binge drinking among adult women. Among adult men, age at migration moderates the association between length of residence and substance use. Specifically, length of residence has more detrimental effects for adolescent immigrants (arriving at age 10-18) on smoking, while its detrimental effects are more pronounced for childhood immigrants (arriving at age 0-9) on binge drinking. We interpret our findings within the critical period model in epidemiological research, concluding that adolescence and childhood are critical life stages that are associated with differential effects of length of residence when looking at smoking and binge drinking among immigrant men.

Rural-to-Urban Migration: Socioeconomic Status But Not Acculturation was Associated with Overweight/Obesity Risk

To investigate whether socioeconomic status (SES) and acculturation predict overweight/obesity risk as well as the mediating effect of physical activity (PA) in the context of internal migration. Cross-sectional study of 587 rural-to-urban migrants participating in the PERU MIGRANT study. Analyses were conducted using logistic regression and structured equation modeling. Interaction effects of SES and acculturation were tested. Models were controlled for age, gender and education. Only SES was a significant predictor of overweight/obesity risk. Lower SES decreased the odds of being overweight/obese by 51.4 %. This association did not vary by gender nor was it explained by PA. Mechanisms underlying the relationship between SES and overweight/obesity may differ depending on the geographic location and sociocultural context of the population studied. Research on internal migration and health would benefit from the development of tailored acculturation measures and the evaluation of exploratory models that include diet.

The Relationship Between Duration of U.S. Residence, Educational Attainment, and Adult Health Among Asian Immigrants

There is substantial educational heterogeneity among Asian immigrants to the United States, suggesting that the association between duration of U.S. residence with their health outcomes and behaviors may vary considerably by educational attainment. Using data from the 2003 New Immigrant Survey (N=2,373), we find strong evidence that the detrimental associations between duration of U.S. residence and self-reported health, activity limitation status, chronic health conditions and current smoking are concentrated among Asian immigrants with less than a high school education; in contrast, the health outcomes and behaviors of Asian immigrants who have at least a high school degree exhibit very few differences by duration of U.S. residence. These distinct duration-health patterns by educational attainment are not explained by duration related differences in country of origin, class of admission, or English speaking skills. We also find a stronger duration relationship with current smoking than those with the health status measures among the least educated Asian men, indicating a potential behaviorally-based explanation for poorer health among Asian immigrant men with longer duration of residence.

Age at Immigration and Kidney Function among Self-Identified Healthy Africans in the United States

Kidney disease disparately affects those of African descent. Age trends have generally been established for kidney function in the overall US population, but the contribution of age at the time of immigration for African immigrants is unknown. To examine the independent and joint effects of age and age at the time of immigration, and kidney function. Estimated glomerular filtration rate (eGFR) was calculated for 93 African immigrants (60 % male; mean age = 33.5). Hierarchical regression and post hoc analyses revealed a significant age × age at the time of immigration interaction after accounting for traditional risk factors among those who immigrated at age ≤21. Younger age at the time of immigration to the US may exacerbate an inverse relationship between age and kidney function in a self-identified healthy African immigrant sample. Investigation of biopsychosocial factors associated with kidney health among African immigrants is warranted.

Impact of acculturation on cardiovascular risk factors among elderly Mexican Americans

PURPOSE

Higher levels of acculturation among Latinos have been shown to be associated with a higher prevalence of cardiovascular (CV) risk factors in some studies of middle-age persons. The association of acculturation and prevalence of CV risk factors in elderly Latinos is less well established.

METHODS

Acculturation was measured using the validated bidimensional Acculturation Rating Scale for Mexican Americans-II. We conducted a cross-sectional analysis of the association of acculturation with prevalence of CV risk factors among 1789 elderly men and women from the Sacramento Area Latino Study on Aging using multivariate linear and logistic regression. We tested for the interaction of acculturation with risk factors by nativity status.

RESULTS

Median age was 69.8 years. Higher acculturation was associated with lower systolic blood pressure, lower low-density lipoprotein, higher high-density lipoprotein, and lower prevalence of CV disease after age and sex adjustment. Higher acculturation remained associated with lower level of low-density lipoprotein and higher level of high-density lipoprotein after full adjustment. Nativity status did not affect these results.

CONCLUSIONS

Contrary to other reports in middle-aged persons, higher levels of acculturation were associated with better lipid profiles and no significant differences in other CV risk factors by acculturation level in elderly Latinos.

Negative Acculturation and Nothing More? Cumulative Disadvantage and Mortality during the Immigrant Adaptation Process among Latinos in the United States

Foreign- and U.S.-born Hispanic health deteriorates with increasing exposure and acculturation to mainstream U.S. society. Because these associations are robust to (static) socioeconomic controls, negative acculturation has become their primary explanation. This overemphasis, however, has neglected important alternative structural explanations. Examining Hispanic mortality using the 1998–2006 U.S. National Health Interview Survey-Linked Mortality File according to nativity, immigrant adaptation measures, and health behaviors, this study presents indirect but compelling evidence that suggests negative acculturation is not the only or main explanation for this deterioration.

Association between chronic kidney disease detected using creatinine and cystatin C and death and cardiovascular events in elderly Mexican Americans: the Sacramento Area Latino Study on Aging

OBJECTIVES

Creatinine, the current clinical standard to detect chronic kidney disease (CKD), is biased by muscle mass, age and race. The authors sought to determine whether cystatin C, an alternative marker of kidney function less biased by these factors, can identify elderly Mexican Americans with CKD who are at high risk for death and cardiovascular disease.

DESIGN

Longitudinal, with mean follow-up of 6.8 years.

SETTING

Sacramento Area Latino Study of Aging (SALSA).

PARTICIPANTS

One thousand four hundred and thirty five Mexican Americans aged 60 to 101.

MEASUREMENTS

Estimated glomerular filtration rate (eGFR, mL/min per 1.73 m(2)) was determined according to creatinine (eGFRcreat) and cystatin C (eGFRcys), and participants were classified into four mutually exclusive categories: CKD neither (eGFRcreat ≥60 mL/min per 1.73 m(2); eGFRcys ≥60 mL/min per 1.73 m(2)), CKD creatinine only (eGFRcreat <60 mL/min per 1.73 m(2); eGFRcys ≥60 mL/min per 1.73 m(2)), CKD cystatin only (eGFRcreat ≥60 mL/min per 1.73 m(2); eGFRcys <60), and CKD both (eGFRcreat <60 mL/min per 1.73 m(2); GFRcys <60 mL/min per 1.73 m(2)). The associations between each CKD classification and all-cause death and cardiovascular (CV) death were studied using Cox regression.

RESULTS

At baseline, mean age was 71 ± 7; 481 (34%) had diabetes mellitus, and 980 (68%) had hypertension. Persons with CKD both had higher risk for all-cause (HR = 2.30, 95% confidence interval (CI) = 1.78-2.98) and CV disease (CVD) (HR = 2.75, 95% CI = 1.96-3.86) death than CKD neither after full adjustment. Persons with CKD cystatin C only were also at greater risk of all-cause (HR = 1.91, 95% CI = 1.37-2.67) and CV (HR = 2.56, 95% CI = 1.64-3.99) death than CKD neither. In contrast, persons with CKD creatinine only were not at greater risk for CV death (HR = 1.39, 95% CI = 0.71-2.72) but were at higher risk for all-cause death (HR = 1.95, 95% CI = 1.27-2.98).

CONCLUSION

Cystatin C may be a useful alternative to creatinine for detecting high risk of death and CVD in elderly Mexican Americans with CKD.

Life-course exposure to early socioeconomic environment, education in relation to late-life cognitive function among older Mexicans and Mexican Americans

OBJECTIVES

To examine the associations between life-course education and late-life cognitive function along with the modifying role of migration history.

METHOD

The combined sample includes 1,789 participants from the Sacramento Area Latino Study on Aging and 5,253 participants from the Mexican Health and Aging Study. Aged 60+ at baseline, participants were classified as Mexican residents, Mexicans-return migrants, Mexicans-immigrants to the United States, and Mexicans-U.S. born. Cognitive function was measured using standardized z scores of a short-term verbal recall test. Multivariate linear regression analysis was conducted.

RESULTS

Participants' z scores were higher among those whose mother had more than elementary education (β = 0.28, p < .05). Participant's education mediated this association. For 5-year difference in education, the cognitive z score increased by 0.3 points for a U.S. born. Results were similar with father's education.

DISCUSSION

Adult educational attainment mediates the effect of childhood socioeconomic status on late-life cognition. Migration plays a role in shaping cognitive aging.

"Vulnerability, Resiliency, and Adaptation: The Health of Latin Americans during the Migration Process to the United States"

In this paper, we offer a general outlook of the health of Latin Americans (with a special emphasis on Mexicans) during the different stages of the migration process to the U.S. given the usefulness of the social vulnerability concept and given that said vulnerability varies conspicuously across the different stages of the migration process. Severe migrant vulnerability during the transit and crossing has serious negative health consequences. Yet, upon their arrival to the U.S., migrant health is favorable in outcomes such as mortality by many causes of death and in several chronic conditions and risk factors, though these apparent advantages seem to disappear during the process of adaptation to the host society. We discuss potential explanations for the initial health advantage and the sources of vulnerability that explain its erosion, with special emphasis in systematic timely access to health care. Given that migration can affect social vulnerability processes in sending areas, we discuss the potential health consequences for these places and conclude by considering the immigration and health policy implications of these issues for the United States and sending countries, with emphasis on Mexico.

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.

Testing healthy immigrant effects among late life immigrants in the United States: using multiple indicators

OBJECTIVE

This study tested a healthy immigrant effect (HIE) and postimmigration health status changes among late life immigrants.

METHODS

Using three waves of the Second Longitudinal Study of Aging (1994-2000) and the linked mortality file through 2006, this study compared (a) chronic health conditions, (b) longitudinal trajectories of self-rated health, (c) longitudinal trajectories of functional impairments, and (d) mortality between three groups (age 70+): (i) late life immigrants with less than 15 years in the United States (n = 133), (ii) longer term immigrants (n = 672), and (iii) U.S.-born individuals (n = 8,642). Logistic and Poisson regression, hierarchical generalized linear modeling, and survival analyses were conducted.

RESULTS

Late life immigrants were less likely to suffer from cancer, had lower numbers of chronic conditions at baseline, and displayed lower hazards of mortality during the 12-year follow-up. However, their self-rated health and functional status were worse than those of their counterparts over time.

CONCLUSION

A HIE was only partially supported among older adults.

Life-course socioeconomic position and incidence of dementia and cognitive impairment without dementia in older Mexican Americans: results from the Sacramento area Latino study on aging

There have been few investigations of the link between changes in life-course socioeconomic position (SEP) and cognitive decline or incidence of dementia. The authors examined the impact of changes in life-course SEP on incidence of dementia and cognitive impairment but not dementia (CIND) over a decade of follow-up. Participants of Mexican origin (n = 1,789) were members of the Sacramento Area Latino Study on Aging cohort. Incidence of dementia/CIND was ascertained by using standard diagnostic criteria. SEP indicators at 3 life stages (childhood, adulthood, and midlife) were used to derive a measure of cumulative SEP (range, 0 to 8) and SEP mobility. Nearly 24% of the sample maintained a low SEP throughout life. Hazard ratios and 95% confidence intervals were computed from Cox proportional hazards regression models. In fully adjusted models, participants with a continuously high SEP had lower hazard ratios for dementia/CIND compared with those with a continuously low SEP at all 3 life stages (hazard ratio = 0.49, 95% confidence interval: 0.24, 0.98; P = 0.04). In age-adjusted models, participants experienced a 16% greater hazard of dementia/CIND with every 1-unit increase in cumulative SEP disadvantage across the life course (hazard ratio = 1.16, 95% confidence interval: 1.01, 1.33; P = 0.04). Early exposures to social disadvantage may increase the risk of late-life dementia.

Differences in cardiovascular risk factors in rural, urban and rural-to-urban migrants in Peru

OBJECTIVES

To assess differences in cardiovascular risk profiles among rural-to-urban migrants and non-migrant groups.

METHODS

Cross-sectional study in Ayacucho and Lima, Peru. Participants were: rural (n=201); rural-to-urban migrants (n=589); and urban (n=199). Cardiovascular risk factors were assessed according to migrant status (migrants vs non-migrants), age at first migration, length of residency in an urban area and lifetime exposure to an urban area.

RESULTS

For most risk factors, the migrant group had intermediate levels of risk between those observed for the rural and urban groups. Prevalence for rural, migrant and urban groups was 3%, 20% and 33%, respectively, for obesity, and 0.8%, 3% and 6% for type-2 diabetes. This gradient of risk was not observed uniformly across all risk factors. Blood pressure did not show a clear gradient of difference between groups. The migrant group had similar systolic blood pressure but lower diastolic blood pressure than the rural group. The urban group had higher systolic blood pressure but similar diastolic blood pressure than rural group. Hypertension was more prevalent among the urban (29%) than both the rural and migrant groups (11% and 16%, respectively). For HbA(1c), although the urban group had higher levels, the migrant and rural groups were similar to each other. No differences were observed in triglycerides between the three groups. Within migrants, those who migrated when aged older than 12 years had higher odds of diabetes, impaired fasting glucose and metabolic syndrome compared to people who migrated at younger ages. Adjustment for age, sex and socioeconomic indicators had little impact on the patterns observed.

CONCLUSIONS

The impact of rural-to-urban migration on cardiovascular risk profile is not uniform across different risk factors, and is further influenced by the age at which migration occurs. A gradient in levels was observed for some risk factors across study groups. This observation indicates that urbanisation is indeed detrimental to cardiovascular health.

Multiple sclerosis in Hispanics: a study of clinical disease expression

Background: Hispanics living with multiple sclerosis (MS) in the United States are not well defined.

Objective: To describe the clinical characteristics of MS among Hispanic Whites (HW) in Southern California with those of non-Hispanic Whites (NHW).

Methods: We performed a medical chart review to identify all cases of HW with MS ( n = 125) who were treated at our institution during a 1-year period. We also identified cases of NHW with MS (100 NHW) treated at those clinics. All HW patients were interviewed to ascertain ancestry including detailed migration history. Disease progression was assessed by ambulatory disability and defined as Expanded Disability Status Scale (EDSS) score ≥6.

Results: Compared with NHW, HW were more likely to have a relapsing–remitting form of MS and a younger age of onset (28.4 ± 0.97 years) with presenting symptoms of optic neuritis and transverse myelitis. However, overall ambulatory disability did not differ between HW and NHW. Migration to the US at age >15 years was associated with increased risk of disability in HW.

Conclusions: HW living in the USA may be at risk of developing MS at an earlier age compared with NHW. Migration history can play an important role in the management of HW with MS.

Migration surrogates and their association with obesity among within-country migrants

Limited studies have evaluated the link between acculturation and health outcomes of within-country migrants. The objective of this study was to evaluate whether well-known acculturation surrogates were associated with obesity among Peruvian rural-to-urban migrants. We performed a cross-sectional survey, the PERU MIGRANT study, using single-stage random sampling. Evaluation included weight, height, and waist circumference (WC) as well as acculturation surrogates. Obesity was assessed using BMI and WC. Length of residence, age at migration, language proficiency, and language preferences (Spanish or Quechua) were assessed in logistic regression models to calculate odd ratios and 95% confidence intervals adjusting for potential confounders. A total of 589 rural-to-urban migrants were enrolled. The mean age was 47.8 (s.d.: 11.7, range: 30-92), and 280 (47.5%) were men. Obesity prevalence assessed using BMI was 30.4% among women and 10.7% among men (P < 0.001), whereas abdominal obesity assessed using WC was 29.1% among women and 19.1% among men (P < 0.01). Obesity was associated with older age at first migration, language speaking proficiency, and language preferences. The association between obesity and acculturation surrogates is variable in this population. Thus, acculturation per se can explore positive channels associated with better health outcomes. The patterns shown in this report suggest a more complex association for these factors.