Diabetes and ageing in the Melbourne Collaborative Cohort Study (MCCS)

Non-communicable diseases in migrants: an expert review

BACKGROUND

Non-communicable diseases (NCDs) remain a major challenge in the 21st century. High-income countries (HICs) populations are ethnically and culturally diverse due to international migration. Evidence suggests that NCDs rates differ between migrants and the host populations in HICs. This paper presents a review of NCDs burden among migrant groups in HICs in Europe, North America and Australia with a major focus on cardiovascular diseases (CVDs), cancer and diabetes.

METHODS

We performed a narrative review consisting of scholarly papers published between 1960 until 2018.

RESULTS

CVD risk differs by country of origin, country of destination and duration of residence. For example, stroke is more common in sub-Sahara African and South-Asian migrants, but lower in North African and Chinese migrants. Chinese migrants, however, have a higher risk of haemorrhagic stroke despite the lower rate of overall stroke. Coronary heart disease (CHD) is more common in South-Asian migrants, but less common in sub-Saharan and north African migrants although the lower risk of CHD in these population is waning. Diabetes risk is higher in all migrants and migrants seem to develop diabetes at an earlier age than the host populations. Migrants in general have lower rates of overall cancer morbidity and mortality than the host populations in Europe. However, migrants have a higher infectious disease-related cancers than the host populations in Europe. In North America, the picture is more complex. Data from cross-national comparisons indicate that migration-related lifestyle changes associated with the lifestyle of the host population in the country of settlement may influence NCDs risk among migrants in a very significant way.

CONCLUSION

With exception of diabetes, which is consistently higher in all migrant groups than in the host populations, the burden of NCDs among migrants seems to depend on the migrant group, country of settlement and NCD type. This suggests that more work is needed to disentangle the key migration-related lifestyle changes and contextual factors that may be driving the differential risk of NCDs among migrants in order to assist prevention and clinical management of NCDs in these populations.

Diabetes and abnormal glucose regulation in the adult population of Burkina Faso: prevalence and predictors

BACKGROUND

The prevalence of diabetes mellitus (DM) is reportedly growing fast in sub-Saharan Africa. There is however a scarcity of epidemiologic data on DM in Burkina Faso. We carried out a secondary analysis of the first survey conducted in Burkina Faso on a nationally representative sample following the World Health Organization (WHO) Stepwise approach to risk factors Surveillance (STEPS) for non-communicable diseases (NCDs) with the aims of identifying the prevalence of NCDs and the prevalence of common risk factors for NCDs. We report here on the prevalence of diabetes and overall abnormal glucose regulation (AGR) and their associated risk factors.

METHODS

In the primary study 4800 individuals were randomly sampled using a stratified multistage clusters sampling process. We used fasting capillary whole blood glucose level to define three glucose regulation statuses using WHO's cut-off levels: normal, diabetes and overall abnormal glucose regulation (impaired fasting glucose and diabetes). Appropriate statistical techniques for the analysis of survey data were used to identify the factors associated with diabetes and abnormal glucose regulation fitting a logistic regression model. Analyses were carried out using Stata Version 14 software.

RESULTS

The prevalence of DM and AGR were respectively 5.8% (95% CI: 5-6.7) and 9% (95% CI: 8-10.1). Significant risk factors for DM include age (OR = 1.9; P = 0.009 for the age group of 55-64), obesity (OR: 2.6; P = 0.001), former smoke (OR:2; P = 0.03), second-hand smoke (OR = 1.7; P = 0.006) and total cholesterol level (OR: 2.1; P = 0.024). The same predictors were also found significantly associated with AGR. In addition, having an history family diabetes was protective against AGR (OR = 0.5; P = 0.032).

CONCLUSION

Diabetes is no longer a rare disease in the adult active population of Burkina Faso. Its burden is significant in both rural and urban areas. Health policies that promote healthy life style are needed to give precedence to the prevention in a context of an under-resourced country.

Socioeconomic indicators in epidemiologic research: A practical example from the LIFEPATH study

Background

Several social indicators have been used in epidemiological research to describe socioeconomic position (SEP) of people in societies. Among SEP indicators, those more frequently used are education, occupational class and income. Differences in the incidence of several health outcomes have been reported consistently, independently from the indicator employed. Main objectives of the study were to present the socioeconomic classifications of the social indicators which will be employed throughout the LIFEPATH project and to compare social gradients in all-cause mortality observed in the participating adult cohorts using the different SEP indicators.

Methods

Information on the available social indicators (education, own and father’s occupational class, income) from eleven adult cohorts participating in LIFEPATH was collected and harmonized. Mortality by SEP for each indicator was estimated by Poisson regression on each cohort and then evaluated using a meta-analytical approach.

Results

In the meta-analysis, among men mortality was significantly inversely associated with both occupational class and education, but not with father’s occupational class; among women, the increase in mortality in lower social strata was smaller than among men and, except for a slight increase in the lowest education category, no significant differences were found.

Conclusions

Among men, the proposed three-level classifications of occupational class and education were found to predict differences in mortality which is consistent with previous research. Results on women suggest that classifying them through their sole SEP, without considering that of their partners, may imply a misclassification of their social position leading to attenuation of mortality differences.

The global dynamics of diabetes and tuberculosis: the impact of migration and policy implications

The convergence between tuberculosis (TB) and diabetes mellitus (DM) will represent a major public health challenge in the near future. DM increases the risk of developing TB by two to three times and also increases the risk of TB treatment failure, relapse, and death. The global prevalence of DM is predicted to rise significantly in the next two decades, particularly in some of the low- and middle-income countries with the highest TB burden. Migration may add further complexity to the effort to control the impact on TB of the growing DM pandemic. Migration may increase the risk of DM, although the magnitude of this association varies according to country of origin and ethnic group, due to genetic factors and lifestyle differences. Migrants with TB may have an increased prevalence of DM compared to the native population, and the risk of TB among persons with DM may be higher in migrants than in autochthonous populations. Screening for DM among migrants, screening migrants with DM for active and latent TB, and improving access to DM care, could contribute to mitigate the effects of DM on TB.

Diabetes in migrants and ethnic minorities in a changing World

On a worldwide scale, the total number of migrants exceeds 200 million and is not expected to reduce, fuelled by the economic crisis, terrorism and wars, generating increasing clinical and administrative problems to National Health Systems. Chronic non-communicable diseases (NCD), and specifically diabetes, are on the front-line, due to the high number of cases at risk, duration and cost of diseases, and availability of effective measures of prevention and treatment. We reviewed the documents of International Agencies on migration and performed a PubMed search of existing literature, focusing on the differences in the prevalence of diabetes between migrants and native people, the prevalence of NCD in migrants vs rates in the countries of origin, diabetes convergence, risk of diabetes progression and standard of care in migrants. Even in universalistic healthcare systems, differences in socioeconomic status and barriers generated by the present culture of biomedicine make high-risk ethnic minorities under-treated and not protected against inequalities. Underutilization of drugs and primary care services in specific ethnic groups are far from being money-saving, and might produce higher hospitalization rates due to disease progression and complications. Efforts should be made to favor screening and treatment programs, to adapt education programs to specific cultures, and to develop community partnerships.

Aging, the metabolic syndrome, and ischemic stroke: redefining the approach for studying the blood-brain barrier in a complex neurological disease

The blood-brain barrier (BBB) has many important functions in maintaining the brain's immune-privileged status. Endothelial cells, astrocytes, and pericytes have important roles in preserving vasculature integrity. As we age, cell senescence can contribute to BBB compromise. The compromised BBB allows an influx of inflammatory cytokines to enter the brain. These cytokines lead to neuronal and glial damage. Ultimately, the functional changes within the brain can cause age-related disease. One of the most prominent age-related diseases is ischemic stroke. Stroke is the largest cause of disability and is third largest cause of mortality in the United States. The biggest risk factors for stroke, besides age, are results of the metabolic syndrome. The metabolic syndrome, if unchecked, quickly advances to outcomes that include diabetes, hypertension, cardiovascular disease, and obesity. The contribution from these comorbidities to BBB compromise is great. Some of the common molecular pathways activated include: endoplasmic reticulum stress, reactive oxygen species formation, and glutamate excitotoxicity. In this chapter, we examine how age-related changes to cells within the central nervous system interact with comorbidities. We then look at how comorbidities lead to increased risk for stroke through BBB disruption. Finally, we discuss key molecular pathways of interest with a focus on therapeutic targets that warrant further investigation.