Experiences of migration and the determinants of obesity among recent Iranian immigrants in Victoria, Australia

Objectives. There is evidence to suggest that immigrant groups from low- or medium-human development index countries show a significant adoption of obesogenic behaviors and experience weight gain following migration to Australia. The objective of this study is to understand the changes that Iranian immigrants experience in relation to the determinants of obesity after migration to Victoria, Australia.

Design. We conducted five focus group discussions with 33 recent Iranian immigrants. This study took an interpretive qualitative approach to data analysis using the constant comparative method.

Results. Participants discussed individual level acculturation (e.g., in diet, body size, attitudes), as well as environmental level changes (e.g., physical/structural and sociocultural) that occurred after immigration. Stress during the initial immigration transition, which affected diet and physical activity habits, was a common experience among participants. Gender and the effect of political/religious changes were also important factors. Participants' discourse largely focused on their ability and willingness to adopt positive health behaviors after migration.

Conclusion. This study provides insight into the effect of migration on the determinants of obesity among Iranian immigrants in Victoria, Australia, and offers a contrast with the existing evidence by considering the experience of a group that is generally well educated, often emigrates for reasons related to personal freedom as opposed to material deprivation, and has rates of obesity similar to high-income countries.

Progression of cardiovascular and endocrine dysfunction in a rabbit model of obesity

In rabbits, mean arterial pressure (MAP) increases in response to fat feeding, but does not increase further with progressive weight gain. We documented the progression of adiposity and the alterations in endocrine/cardiovascular function in response to fat feeding in rabbits, to determine whether stabilization of MAP after 3 weeks could be explained by stabilization of neurohormonal factors. Rabbits were fed a control diet or high-fat diet for 9 weeks (n¼23). Fat feeding progressively increased body mass and adiposity. Heart rate (HR) was elevated by week 3 (15±3%) but changed little thereafter. The effects of fat feeding on MAP were dependent on baseline MAP and peaked at 3 weeks. From baseline, MAP p80mmHg, MAP had increased by 8.1±1.3, 4.7±1.7 and 5.6±1.2mmHg, respectively, 3, 6 and 9 weeks after commencing the high-fat diet, but by only 2.6±1.5, 3.0±1.7 and 3.9±1.4mmHg, respectively, in control rabbits. Fat feeding did not increase MAP from a baseline 480mmHg. Plasma concentrations of leptin and insulin increased during the first 3–6 weeks of fat feeding and then stabilized (increasing by 111±17% and 731±302% by week 9, respectively), coinciding with the pattern of changes in MAP and HR. Plasma total cholesterol, triglycerides, renin activity, aldosterone and atrial natriuretic peptide were not significantly altered by fat feeding. Given that the changes in plasma leptin and insulin mirrored the changes in MAP and HR, leptin and insulin may be important factors in the development of hypertensionand tachycardia in the rabbit model of obesity.

Acculturation and obesity among migrant populations in high income countries - a systematic review

Background:
There is evidence to suggest that immigrant populations from low or medium-income countries to high income countries show a significant change in obesogenic behaviors in the host society, and that these changes are associated with acculturation. However, the results of studies vary depending on how acculturation is measured. The objective of this study is to systematically review the evidence on the relationship between acculturation - as measured with a standardized acculturation scale - and overweight/obesity among adult migrants from low/middle countries to high income countries.

Methods:

A health promotion intervention can affect diet quality in early childhood

Initiatives to promote children’s nutrition and prevent childhood obesity are vital. Dietary patterns are a useful way to characterize whole diets, though no previous early childhood health promotion trial has assessed intervention impact using this approach. This research aimed to assess the effect on young children’s dietary patterns of a healthy eating and physical activity intervention. The Melbourne Infant Feeding Activity and Nutrition Trial (InFANT) Program was a health promotion cluster-randomized controlled trial involving 542 families. Child diets were assessed by multiple 24-hour recalls post-intervention, at approximately 18 months of age. An Obesity Protective Dietary Index was created, and dietary patterns were also assessed by principal components analysis. These outcomes were used to compare intervention and control participants to test the effectiveness of the intervention. Children in the intervention arm scored significantly higher (15.6 ± 5.9) than those in the control arm (14.5 ± 6.7) for the Obesity Protective Dietary Index (scores out of 30, p=0.01). Three dietary patterns were identified by principal components analysis, however, scores were not significantly different between intervention and control arms. In conclusion, this paper presents novel results in both the evaluation of an early childhood health promotion intervention and in the assessment of child dietary patterns. The results highlight the capacity for such an initiative to improve child diets, and the need for further research in this area.

Components of the diet associated with child adiposity: a cross-sectional study

Objective:
This study sought to determine which components of youths' diets were related to adiposity while controlling for potential often-neglected confounders such as moderate to vigorous physical activity (MVPA) and dietary reporting error. Secondary goals of this study were to determine the extent to which MVPA confounded the associations between diet and adiposity and whether associations between diet and adiposity would differ depending on reporting error.

Methods:
An ethnically diverse urban sample of 342 children aged 9–10 years and 323 adolescents aged 17–18 years were recruited for this cross-sectional study. Body mass index (BMI) and waist circumference (WC) were measured in the school; dietary assessment included three 24-hour recalls via telephone in the evenings, and MVPA assessment included 5 days of accelerometry. Over (n = 68), under (n = 250), or plausible (n = 347) dietary intake reporters were identified with the Huang calculation method. Linear regression assessed the relationship between adiposity indicators (BMI z-score and WC) and components of the diet (energy intake, food groups, macronutrients) after controlling for reporting error, demographic variables, and MVPA.

Results:
When dietary reporting error and potential confounders such as MVPA and demographic variables were controlled, energy intake (EI), vegetables, refined grains, total fat, total protein, and total carbohydrate were positively related to BMI z-score and WC and artificially sweetened beverages to WC. MVPA was a significant confounder. For BMI z-score, but not WC, relationships and strength of these relationships differed depending on dietary reporting error group (plausible, underreporter, overreporter).

Conclusions:
Among plausible reporters, as expected, EI, refined grains, and all macronutrients were positively related to adiposity; however, artificially sweetened beverages and vegetables, which are low-energy-dense foods, were also positively related to adiposity. Reporting error interfered with associations between diet and BMI z-score but not WC, suggesting WC is a more robust measure of adiposity in relation to diet.

Severe obesity and diabetes self-care attitudes, behaviours and burden: implications for weight management from a matched case-controlled study.

Aims
To investigate whether diabetes self-care attitudes, behaviours and perceived burden, particularly related to weight management, diet and physical activity, differ between adults with Type 2 diabetes who are severely obese and matched non-severely obese control subjects.

Methods
The 1795 respondents to the Diabetes MILES—Australia national survey had Type 2 diabetes and reported height and weight data, enabling BMI calculation: 530 (30%) were severely obese (BMI ≥ 35 kg/m2; median BMI = 41.6 kg/m2) and these were matched with 530 control subjects (BMI < 35 kg/m2; median BMI = 28.2 kg/m2). Diabetes self-care behaviours, attitudes and burden were measured with the Diabetes Self-Care Inventory—Revised. Within-group and between-group trends were examined.

Results
The group with BMI ≥ 35 kg/m2 was less likely to achieve healthy diet and exercise targets, placed less importance on diet and exercise recommendations, and found the burden of diet and exercise recommendations to be greater than the group with BMI < 35 kg/m2. The group with BMI ≥ 35 kg/m2 was more likely to be actively trying to lose weight, but found weight control a greater burden. These issues accentuated with increasing obesity and were greatest in those with BMI > 45 kg/m2. There were no between-group differences in other aspects of diabetes self-care: self-monitoring of blood glucose, use of medications and smoking. Moderate-to-severe symptoms of depression were independently associated with reduced likelihood of healthy diet and physical activity, and with greater burden associated with diet, physical activity and weight management.

Conclusions
Severely obese people with diabetes demonstrated self-care attitudes, behaviours and burdens that infer barriers to weight loss. However, other important diabetes self-care behaviours are supported equally by severely obese and non-severely obese individuals.

Systematic review of lifestyle interventions to limit postpartum weight retention: implications for future opportunities to prevent maternal overweight and obesity following childbirth

Postpartum weight retention can predict future weight gain and long-term obesity. Moreover, failure to lose weight gained during pregnancy can lead to increased body mass index for subsequent pregnancies, increasing the risk of adverse maternal and foetal pregnancy outcomes. This systematic review evaluates the effectiveness of lifestyle interventions aimed at reducing postpartum weight retention. Seven electronic databases were searched for intervention studies and trials enrolling women with singleton pregnancies and published in English from January 1990 to October 2012. Studies were included when postpartum weight was a main outcome and when diet and/or exercise and/or weight monitoring were intervention components. No limitations were placed on age, body mass index or parity. Eleven studies were identified as eligible for inclusion in this review, of which 10 were randomized controlled trials. Seven studies were successful in decreasing postpartum weight retention, six of which included both dietary and physical activity components, incorporated via a range of methods and delivered by a variety of health practitioners. Few studies utilized modern technologies as alternatives to traditional face-to-face support and cost-effectiveness was not assessed in any of the studies. These results suggest that postpartum weight loss is achievable, which may form an important component of obesity prevention in mothers; however, the optimal setting, delivery, intervention length and recruitment approach remains unclear.

The effect of an early childhood obesity intervention on father's obesity risk behaviors: the Melbourne InFANT program

Background
To investigate the effect of an early childhood obesity prevention intervention, incorporating a parent modelling component, on fathers’ obesity risk-related behaviours.

Methods
Cluster randomized-controlled trial in the setting of pre-existing first-time parents groups organised by Maternal and Child Health Nurses in Victoria, Australia. Participants were 460 first-time fathers mean age = 34.2 (s.d.4.90) years. Dietary pattern scores of fathers were derived using principal component analysis, total physical activity and total television viewing time were assessed at baseline (infant aged three to four months) and after 15 months.

Results
No significant beneficial intervention effect was observed on fathers’ dietary pattern scores, total physical activity or total television viewing time.

Conclusion
Despite a strong focus on parent modelling (targeting parents own diet, physical activity and television viewing behaviours), and beneficial impact on mothers’ obesity risk behaviours, this intervention, with mothers as the point of contact, had no effect on fathers’ obesity risk-related behaviours. Based on the established links between children’s obesity risk-related behaviors and that of their fathers, a need exists for research testing the effectiveness of interventions with a stronger engagement of fathers.