Migration and its impact on adiposity and type 2 diabetes

Ethnic variation in fat and lean body mass and the association with insulin resistance

CONTEXT

Body fat distribution varies among different ethnic groups, yet less is known regarding differences in lean mass and how this may affect insulin resistance.

OBJECTIVE

Our objective was to compare total body fat to lean mass ratio (F:LM) in Aboriginal, Chinese, European, and South Asian individuals with differences in insulin resistance.

PARTICIPANTS, DESIGN, AND SETTING

Aboriginal (196), Chinese (222), European (202), and South Asian (208) individuals were recruited across a range of body mass index to participate in this cross-sectional community study.

MAIN OUTCOME MEASURES

Total body fat, lean mass, and insulin resistance were assessed using homeostasis model assessment (HOMA).

RESULTS

After adjustment for confounders and at a given body fat, South Asian men had less lean mass than Aboriginal [3.42 kg less; 95% confidence interval (CI) = 1.55-5.29], Chinese (3.01 kg less; 95% CI = 1.33-4.70), and European (3.57 kg less; 95% CI = 1.82-5.33) men, whereas South Asian women had less lean mass than Aboriginal (1.98 kg less; 95% CI = 0.45-3.50), Chinese (2.24 kg less; 95% CI = 0.81-3.68), and European (2.97 kg less; 95% CI = 1.67-4.27) women. In adjusted models, F:LM was higher in South Asian compared with Chinese and European men and higher in South Asian compared with Aboriginal, Chinese, and European women (P < 0.01 for all). Insulin and HOMA were greatest in South Asians after adjustment; however, these differences were no longer apparent when F:LM was considered.

CONCLUSIONS

South Asians have a phenotype of high fat mass and low lean mass, which may account for greater levels of insulin and HOMA compared with other ethnic groups.

Cardiovascular risk factors in Assyrians/Syrians and native Swedes with type 2 diabetes: a population-based epidemiological study

BACKGROUND

A large number of people throughout the world have diabetes and the prevalence is increasing. Persons with diabetes have a twice higher risk of cardiovascular disease than those without diabetes. There is a lack of studies focusing on cardiovascular risk factors in Assyrians/Syrians with type 2 diabetes. The aim of this study is to estimate the prevalence of some cardiovascular risk factors among Assyrians/Syrians and native Swedes with type 2 diabetes and to study whether the association between ethnicity and cardio-vascular risk factors remains after adjustment for age, gender, employment status and housing tenure.

METHODS

In the Swedish town of Södertälje 173 Assyrians/Syrians and 181 ethnic Swedes with type 2 diabetes participated in a study evaluating cardiovascular risk factors such as increased haemoglobin A1c (HbA1c), high blood lipids (total serum cholesterol and triglycerides), hypertension and high urinary albumin. The associations between the outcome variables and sociodemographic characteristics were estimated using unconditional logistic regression.

RESULTS

The prevalence of increased triglycerides in Swedish-born subjects and Assyrian-Syrians was 61.5% and 39.7% respectively. Swedes had a prevalence of hypertension 76.8% compared to 57.8% in Assyrians/Syrians. In the final logistic models adjusted for gender, age, housing and employment the odds ratio (OR) for Swedish-born subjects for increased triglycerides was 2.80 (95% CI1.61-4.87) and for hypertension 2.32 (95% CI 1.35-4.00) compared to Assyrians-Syrians.

CONCLUSION

Ethnic Swedes had higher prevalence of increased triglycerides and hypertension than Assyrians/Syrians. Total cholesterol, HbA1c and urinary albumin did not differ between the two ethnic groups.

Meat consumption and the risk of type 2 diabetes: a systematic review and meta-analysis of cohort studies

AIMS/HYPOTHESIS

Diet is thought to play an important role in the aetiology of type 2 diabetes. Previous studies have found positive associations between meat consumption and the risk of type 2 diabetes, but the results have been inconsistent. We conducted a systematic review and meta-analysis of cohort studies of meat consumption and type 2 diabetes risk.

METHODS

We searched several databases for cohort studies on meat consumption and type 2 diabetes risk, up to December 2008. Summary relative risks were estimated by use of a random-effects model.

RESULTS

We identified 12 cohort studies. The estimated summary RR and 95% confidence interval of type 2 diabetes comparing high vs low intake was 1.17 (95% CI 0.92-1.48) for total meat, 1.21 (95% CI 1.07-1.38) for red meat and 1.41 (95% CI 1.25-1.60) for processed meat. There was heterogeneity amongst the studies of total, red and processed meat which, to some degree, was explained by the study characteristics.

CONCLUSIONS/INTERPRETATION

These results suggest that meat consumption increases the risk of type 2 diabetes. However, the possibility that residual confounding could explain this association cannot be excluded.

Effectiveness of prevention programmes for obesity and chronic diseases among immigrants to developed countries - a systematic review

OBJECTIVE

To determine whether interventions tailored specifically to particular immigrant groups from developing to developed countries decrease the risk of obesity and obesity-related diseases.

DESIGN

Databases searched were MEDLINE (1966-September 2008), CINAHL (1982-September 2008) and PsychINFO (1960-September 2008), as well as Sociological Abstracts, PsychARTICLES, Science Direct, Web of Knowledge and Google Scholar. Studies were included if they were randomised control trials, 'quasi-randomised' trials or controlled before-and-after studies. Due to the heterogeneity of study characteristics only a narrative synthesis was undertaken, describing the target population, type and reported impact of the intervention and the effect size.

RESULTS

Thirteen studies met the inclusion criteria. Ten out of thirteen (77 %) studies focused on diabetes, seven (70 %) of which showed significant improvement in addressing diabetes-related behaviours and glycaemic control. The effect on diabetes was greater in culturally tailored and facilitated interventions that encompassed multiple strategies. Six out of the thirteen studies (46 %) incorporated anthropometric data, physical activity and healthy eating as ways to minimise weight gain and diabetes-related outcomes. Of the six interventions that included anthropometric data, only two (33 %) reported improvement in BMI Z-scores, total skinfold thickness or proportion of body fat. Only one in three (33 %) of the studies that included cardiovascular risk factors reported improvement in diastolic blood pressure after adjusting for baseline characteristics. All studies, except four, were of poor quality (small sample size, poor internal consistency of scale, not controlling for baseline characteristics).

CONCLUSIONS

Due to the small number of studies included in the present review, the findings that culturally tailored and facilitated interventions produce better outcomes than generalised interventions, and that intervention content is more important than the duration or venue, require further investigation.

[Prevalence of diagnosed chronic disorders in the immigrant and native population]

OBJECTIVE

To estimate the prevalence rates of chronic disorders in immigrants and to compare them with those in the native population, based on electronic clinical records in primary care (ECRPC).

METHODS

We performed a descriptive cross-sectional study in patients aged 16 and over included in the Madrid Regional Public Health System. Age-adjusted prevalence rates for each sex and region were estimated on the basis of medically examined cases registered in the ECRPC with any new data entry made in 2005 or 2006.

RESULTS

After age-adjustment, a total of 36.8% immigrants had some chronic health problem (vs. 55.3% natives). These disorders were more frequent among women and among the population from Africa and Latin America. The highest overall prevalence rates in the foreign population were allergy (10.2% crude rate), low-back pain (9.1%), chronic skin problems (6.8%) and mental disorders (6.4%).

CONCLUSIONS

The prevalence rate of chronic disease is lower in the foreign population and differs according to sex and country of origin.

Cultural and social influences on food consumption in dutch residents of Turkish and moroccan origin: a qualitative study

OBJECTIVE

To explore the social and cultural influences on food intake in 2 non-Western migrant origin groups. The authors were particularly interested in the influence of the traditional culture and its relevance within the context of migration and associated changes in social, economic and cultural context, including acculturation.

DESIGN

Qualitative focus group discussions.

SETTING

City of Amsterdam, the Netherlands.

PARTICIPANTS

Young adults of Turkish and Moroccan migrant origin.

PHENOMENON OF INTEREST

Social and cultural influences on food intake.

ANALYSIS

Focus groups were recorded, transcribed, and analyzed using framework analysis.

RESULTS

A dominant theme that emerged is that of hospitality and the central role of food herein. Hospitality is rooted within the cultural and religious tradition of both groups. Additional themes that emerged were: cultural identity; migration and lifestyle change; and acculturation.

CONCLUSIONS AND IMPLICATIONS

Among Dutch residents of Turkish and Moroccan migrant origin, the central role of food in culture coupled with the changes that come about as a result of migration create an environment of abundance that can lead to overeating, which may impact energy balance and overweight development. These results indicate that younger members of migrant origin populations continue to value their traditional food cultures, underpinning the need for interventions to be culturally sensitive.

Is migration status a determinant of urban nutrition insecurity? Empirical evidence from Mumbai city, India

From an economic perspective that understood it as a spillover of development, migration is now also the subject of socioeconomic investigation incorporating the problems of assimilation, relative deprivation and isolation. The corollary is an increased emphasis on economic and social understanding of migration and its consequences. This entails studying migration or migrants in terms of factors beyond income. Health outcome is important among these non-income factors but at the same time remains less studied. Although there have been a few influential studies on health issues as linked to migration status, the issue of malnutrition in this context continues to be under-researched. This paper explores, theoretically and empirically, migration status and malnutrition in Mumbai in India. An econometric analysis of Demographic and Health Survey data gives insight into the dynamics of child and maternal undernutrition as mediated by migration status in Mumbai.

Influence of acculturation among Tunisian migrants in France and their past/present exposure to the home country on diet and physical activity

Objective

To study how dietary patterns and physical activity vary with acculturation and with past and current exposure to socio-cultural norms of the home country among Tunisian migrants.

Design

A retrospective cohort study was conducted using quota sampling (n 150) based on age and residence. Dietary intake was assessed using a validated FFQ. Physical activity level and dietary aspects were compared according to length of residence (acculturation), age at migration (past exposure) and social ties with the home country (current exposure).

Subjects and setting

Tunisian migrant men residing in the South of France.

Results

Migrants who had lived in France for more than 9 years had a higher percentage contribution of meat to energy intake (P = 0·04), a higher Na intake (P = 0·04), a lower percentage contribution of sugar and sweets (P = 0·04) and a lower percentage of carbohydrates (P = 0·03) than short-term migrants. Men who migrated before 21 years of age had a higher Na intake than ‘late’ migrants (P = 0·02). Men who had distant social ties with Tunisia had a lower physical activity level (P = 0·01) whereas men who had close ties had a higher percentage of fat (P = 0·01) and a higher ratio of MUFA to SFA (P = 0·02).

Conclusions

Acculturation led to a convergence of some characteristics to those of the host population, while some results (meat and salt consumption) were at variance with other acculturation studies. Past and current exposure to the home country helped maintain some positive aspects of the diet. Nevertheless, present dietary changes in Tunisia could soon lessen these features.

The association between body mass index and hypertension is different between East and Southeast Asians

BACKGROUND

Few studies have allowed direct comparison of the association between body mass index (BMI; in kg/m2) and hypertension in different Asian ethnicities.

OBJECTIVE

We compared the association of BMI with hypertension in Chinese, Indonesian, and Vietnamese adults and determined BMI cutoffs that best predicted hypertension in these populations.

DESIGN

We included 7562 Chinese, 18,502 Indonesian, and 77,758 Vietnamese participants aged 18-65 y. Blood pressure, weight, and height were measured by trained health workers. To define an optimal BMI cutoff, we computed and searched for the shortest distance on receiver operating characteristic curves.

RESULTS

Despite a low mean BMI, the prevalences of hypertension in Chinese, Indonesian, and Vietnamese men were 22.9%, 24.8%, and 14.4%, respectively, and in women were 16.6%, 26.9%, and 11.7%, respectively. At all BMI levels, the sex-specific prevalence of hypertension was higher in Indonesian adults than in Chinese and Vietnamese adults (P < 0.05 at almost all BMI levels). The overall and stratified analyses suggested optimal BMI cutoffs of 23-24, 21-22.5, and 20.5-21 for Chinese, Indonesian, and Vietnamese adults, respectively. The cutoffs were approximately 0.5-1.0 units higher in women than in men and in the older (41-65 y) than in the younger (18-40 y) participants.

CONCLUSIONS

The study showed an ethnic difference in the BMI-hypertension association and in optimal BMI cutoffs between Chinese, Indonesian, and Vietnamese adults. Country-specific or even country-, sex-, and age-specific BMI cutoffs might be needed to identify persons at high risk of cardiovascular diseases.

Diabetes in African American youth: prevalence, incidence, and clinical characteristics: the SEARCH for Diabetes in Youth Study

OBJECTIVE

To report the prevalence and incidence of type 1 and type 2 diabetes among African American youth and to describe demographic, clinical, and behavioral characteristics.

RESEARCH DESIGN AND METHODS

Data from the SEARCH for Diabetes in Youth Study, a population-based, multicenter observational study of youth with clinically diagnosed diabetes aged 0-19 years, were used to estimate the prevalence for calendar year 2001 (692 cases) and incidence based on 748 African American case subjects diagnosed in 2002-2005. Characteristics of these youth were obtained during a research visit for 436 African American youth with type 1 diabetes and 212 African American youth with type 2 diabetes.

RESULTS

Among African American youth aged 0-9 years, prevalence (per 1,000) of type 1 diabetes was 0.57 (95% CI 0.47-0.69) and for those aged 10-19 years 2.04 (1.85-2.26). Among African American youth aged 0-9 years, annual type 1 diabetes incidence (per 100,000) was 15.7 (13.7-17.9) and for those aged 10-19 years 15.7 (13.8-17.8). A1C was >or=9.5% among 50% of youth with type 1 diabetes aged >or=15 years. Across age-groups and sex, 44.7% of African American youth with type 1 diabetes were overweight or obese. Among African American youth aged 10-19 years, prevalence (per 1,000) of type 2 diabetes was 1.06 (0.93-1.22) and annual incidence (per 100,000) was 19.0 (16.9-21.3). About 60% of African American youth with type 2 diabetes had an annual household income of <$25,000. Among those aged >or=15 years, 27.5% had an A1C >or=9.5%, 22.5% had high blood pressure, and, across subgroups of age and sex, >90% were overweight or obese.

CONCLUSIONS

Type 1 diabetes presents a serious burden among African American youth aged <10 years, and African American adolescents are impacted substantially by both type 1 and type 2 diabetes.

Ethnic differences in metabolic syndrome among overweight and obese children and adolescents: the Oslo Adiposity Intervention Study

AIM

Are there differences in the prevalence of metabolic syndrome between obese and overweight Norwegian and immigrant children and adolescents?

METHODS

Two hundred and three overweight and obese Norwegian, Pakistani, Tamil and Turkish patients aged 6-17 years living in Norway were included. Metabolic syndrome was defined as the presence of at least three abnormal values of waist circumference, blood pressure, fasting triglycerides, fasting glucose and HDL cholesterol.

RESULTS

The prevalence of metabolic syndrome was significantly higher among the immigrant compared to Norwegian subjects when adjusted for age, gender and BMI-Z-score (20.8 vs. 30.6%; OR = 2.2, 95% CI = 1.05-4.77). The prevalence of metabolic syndrome increased with increasing severity of obesity and reached 50% in severely obese immigrants and 30% in severely obese Norwegians. Among the overweight subjects metabolic syndrome prevalence was 23.5% among immigrants and 19.4% among Norwegians.

CONCLUSION

Metabolic syndrome was found more frequently among children and adolescents with Middle Eastern and South Asian origins than Norwegians. Differences were found even after adjustment for age, sex and degree of obesity. This suggests that ethnic minorities may have an increased sensitivity to adiposity and need more aggressive prevention and treatment than their Norwegian counterparts.

South Asian diets and insulin resistance

A role of dietary nutrients in relation to insulin resistance has been suggested but conclusive evidence in human beings is lacking. Asian Indians and South Asians are prone to develop insulin resistance and the metabolic syndrome. In the present paper, data pertaining to nutrient intake, insulin resistance and cardiovascular risk factors in Asian Indians and South Asians have been reviewed. In these populations, several dietary imbalances have been reported: low intake of MUFA, n-3 PUFA and fibre, and high intake of fats, saturated fats, carbohydrates and trans-fatty acids (mostly related to the widespread use of Vanaspati, a hydrogenated oil). Some data suggest that these nutrient imbalances are associated with insulin resistance, dyslipidaemia and subclinical inflammation in South Asians. Specifically, in children and young individuals, a high intake of n-6 PUFA is correlated with fasting hyperinsulinaemia, and in adults, high-carbohydrate meal consumption was reported to cause hyperinsulinaemia, postprandial hyperglycaemia and hypertriacylglycerolaemia. Dietary supplementation with n-3 PUFA leads to an improved lipid profile but not insulin sensitivity. Inadequate maternal nutrition in pregnancy, low birth weight and childhood 'catch-up' obesity may be important for the development of the metabolic syndrome and diabetes. Even in rural populations, who usually consume traditional frugal diets, there is an increasing prevalence of cardiovascular risk factors and the metabolic syndrome due to changes in diets and lifestyle. Nationwide community intervention programmes aimed at creating awareness about the consequences of unhealthy food choices and replacing them by healthy food choices are urgently needed in urban and rural populations in India, other countries in South Asia and in migrant South Asians.

Overweight and obesity among Ghanaian residents in The Netherlands: how do they weigh against their urban and rural counterparts in Ghana?

OBJECTIVE

To investigate differences in overweight and obesity between first-generation Dutch-Ghanaian migrants in The Netherlands and their rural and urban counterparts in Ghana.

DESIGN

Cross-sectional study.

SUBJECTS

A total of 1471 Ghanaians (rural Ghanaians, n 532; urban Ghanaians, n 787; Dutch-Ghanaians, n 152) aged > or = 17 years.

MAIN OUTCOME MEASURES

Overweight (BMI > or = 25 kg/m2) and obesity (BMI > or = 30 kg/m2).

RESULTS

Dutch-Ghanaians had a significantly higher prevalence of overweight and obesity (men 69.1%, women 79.5%) than urban Ghanaians (men 22.0%, women 50.0%) and rural Ghanaians (men 10.3%, women 19.0%). Urban Ghanaian men and women also had a significantly higher prevalence of overweight and obesity than their rural Ghanaian counterparts. In a logistic regression analysis adjusting for age and education, the odds ratios for being overweight or obese were 3.10 (95% CI 1.75, 5.48) for urban Ghanaian men and 19.06 (95% CI 8.98, 40.43) for Dutch-Ghanaian men compared with rural Ghanaian men. Among women, the odds ratios for being overweight and obese were 3.84 (95% CI 2.66, 5.53) for urban Ghanaians and 11.4 (95% CI 5.97, 22.07) for Dutch-Ghanaians compared with their rural Ghanaian counterparts.

CONCLUSION

Our current findings give credence to earlier reports of an increase in the prevalence of overweight/obesity with urbanization within Africa and migration to industrialized countries. These findings indicate an urgent need to further assess migration-related factors that lead to these increases in overweight and obesity among migrants with non-Western background, and their impact on overweight- and obesity-related illnesses such as diabetes among these populations.

Changes in dietary habits following temporal migration. The case of international students in Belgium

This paper reports findings from a cross-sectional survey carried out in April-May 2006 among international students enrolled at Ghent University in Belgium. The aim of the study was to assess their knowledge and attitudes related to nutrition, perceived changes in dietary habits, perceived barriers to healthy eating and the determinants of dietary changes since their arrival in Belgium. In total, 235 students from 60 countries participated. Following the reported dietary changes, which were factor-analyzed into "less energy-dense" foods, "more fruits and vegetables" and "less processed" foods, three clusters could be identified. Cluster 1 composed of students who increased their fruits, vegetables and fiber intake. Cluster 2, the largest, reported dietary changes overall and in particular towards less processed foods. Cluster 3 composed of students who changed in the main towards less energy-dense foods. Gender differences were observed in healthy dietary changes, particularly in males. Healthier choices were hindered by a perceived unavailability of healthy food products. Gender and availability of healthy foods should be taken into consideration when informing temporal migration populations, such as international students in this study, about the healthy food options available during their stay in a different cultural, food and dietary environment.

Estimation of diabetes prevalence among immigrants from the Middle East in Sweden by using three different data sources

AIMS

To estimate diabetes prevalence in immigrants from the Middle East in Sweden compared with Swedish-born subjects. This group accounts for around 15% of Sweden's non-European immigrants.

METHODS

Three samples were used: self-reported diabetes in a random sample (SALLS sample) of subjects aged 35-64 years in Sweden (n=22,032); known diabetes among patients aged 35-64 years in primary care (PC) at four primary healthcare centers in Stockholm County (n=30,679); and known and newly diagnosed diabetes in a random population sample of subjects aged 60 years in Stockholm County (n=4106).

RESULTS

The odds ratio (OR) for subjects from the Middle East was: 1.69 (95% confidence interval [CI] 0.96-2.99) in the SALLS sample; 4.43 (95% CI 3.38-5.56) in the PC sample; and 3.96 (95% CI 1.98-7.92) in the age-60 sample, compared with native Swedes. Subjects from European and other Organization for Economic Cooperation and Development (OECD) countries showed an excess risk only in the SALLS sample (1.43, 95% CI 1.11-1.83).

CONCLUSIONS

Immigrants from the Middle East showed a four-fold higher risk of diabetes compared with Swedish-born subjects in two of the three data sources. More studies are needed to confirm these results, but the findings call for targeted preventative strategies in this population group.

Does economic development contribute to sex differences in ischaemic heart disease mortality? Hong Kong as a natural experiment using a case-control study

BACKGROUND

The male excess risk of premature ischemic heart disease (IHD) mortality may be partially due to an unknown macro-environmental influence associated with economic development. We examined whether excess male risk of IHD mortality was higher with birth in an economically developed environment.

METHODS

We used multivariable logistic regression in a population-based case-control study of all adult deaths in Hong Kong Chinese in 1998 to compare sex differences in IHD mortality (1,189 deaths in men, 1,035 deaths in women and 20,842 controls) between Hong Kong residents born in economically developed Hong Kong or in contemporaneously undeveloped Guangdong province in China.

RESULTS

Younger (35-64 years) native-born Hong Kong men had a higher risk of IHD death than such women (odds ratio 2.91, 95% confidence interval 1.66 to 5.13), adjusted for age, socio-economic status and lifestyle. There was no such sex difference in Hong Kong residents who had migrated from Guangdong. There were no sex differences in pneumonia deaths by birth place.

CONCLUSION

Most of these people migrated as young adults; we speculate that environmentally mediated differences in pubertal maturation (when the male disadvantage in lipids and fat patterning emerges) may contribute to excess male premature IHD mortality in developed environments.

The impact of medication regimen factors on adherence to chronic treatment: a review of literature

This article reviews recent literature in chronic illness or long-term health management including asthma, contraception, diabetes, HIV disease, and hypertension/cardiovascular disease, mental disorders, pain, and other diseases to determine the relationship between regimen factors and adherence to medications. The authors conducted an electronic literature search to detect articles published between 1998 and 2007. Articles were included if they pertained to a chronic illness or to contraception, included a clear definition of how adherence was measured, and included regimen factors as primary or secondary explanatory variables. Methodology of the studies varied greatly, as did methods of measuring adherence and regimen factors. Surprisingly few of these articles concerned (1) chronic treatment, (2) regimen factors such as dosing, pill burden, and regimen complexity, and (3) adherence measured in a clear manner. Most studies failed to use state-of-the-art methods of measuring adherence. Despite these flaws, a suggestive pattern of the importance of regimen factors, specifically dose frequency and regimen complexity, emerged from this review.