Andre Renzaho

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

BackgroundThere 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.MethodsA systematic review of relevant studies was undertaken using six EBSCOhost databases and following the Centre for Reviews and Dissemination’s Guidance for Undertaking Reviews in Health Care.ResultsThe initial search identified 1135 potentially relevant publications, of which only nine studies met the selection criteria. All of the studies were from the US with migrant populations from eight different countries. Six studies employed bi-directional acculturation scales and three used uni-directional scales. Six studies indicated positive general associations between higher acculturation and body mass index (BMI), and three studies reported that higher acculturation was associated with lower BMI, as mainly among women.ConclusionDespite the small number of studies, a number of potential explanatory hypotheses were developed for these emerging patterns. The ‘Healthy Migrant Effect’ may diminish with greater acculturation as the host culture potentially promotes more unhealthy weight gain than heritage cultures. This appears particularly so for men and a rapid form of nutrition transition represents a likely contributor. The inconsistent results observed for women may be due to the interplay of cultural influences on body image, food choices and physical activity. That is, the Western ideal of a slim female body and higher values placed on physical activity and fitness may counteract the obesogenic food environment for female migrants.

Maintenance of traditional cultural orientation is associated with lower rates of obesity and sedentary behaviours among African migrant children to Australia.

Background:Migrants from developing to developed countries rapidly develop more obesity than the host population. While the effects of socio-economic status on obesity are well established, the influence of cultural factors, including acculturation, is not known.Objective:To examine the association between acculturation and obesity and its risk factors among African migrant children in Australia.Design and participants:A cross-sectional study using a non-probability sample of 3- to 12-year-old sub-Saharan African migrant children. A bidimensional model of strength of affiliation with African and Australian cultures was used to divide the sample into four cultural orientations: traditional (African), assimilated (Australian), integrated (both) and marginalized (neither).Main outcome measures:Body mass index (BMI), leisure-time physical activity (PA) and sedentary behaviours (SBs) and energy density of food.Results:In all, 18.4% (95% confidence interval (CI): 14–23%) were overweight and 8.6% (95% CI: 6–12%) were obese. After adjustment for confounders, integrated (β=1.1; P<0.05) and marginalized (β=1.4; P<0.01) children had higher BMI than traditional children. However, integrated children had significantly higher time engaged in both PA (β=46.9, P<0.01) and SBs (β=43.0, P<0.05) than their traditional counterparts. In comparison with traditional children, assimilated children were more sedentary (β=57.5, P<0.01) while marginalization was associated with increased consumption of energy-dense foods (β=42.0, P<0.05).Conclusions:Maintenance of traditional orientation was associated with lower rates of obesity and SBs. Health promotion programs and frameworks need to be rooted in traditional values and habits to maintain and reinforce traditional dietary and PA habits, as well as identify the marginalized clusters and address their needs.

Vitamin D, obesity, and obesity-related chronic disease among ethnic minorities: A systematic review

OBJECTIVE To assess the association between 25-hydroxyvitamin D (25[OH]D) status and obesity, cardiovascular diseases (CVDs), the metabolic syndrome, and type 2 diabetes mellitus (T2DM) in ethnic minorities. METHODS Databases searched were CINHAL with full text, Global Health, MEDLINE with full text, and PsycINFO from 1980 through 2010 (February). Studies were included if they 1) targeted immigrants from low- to high-income countries or ethnic minorities, 2) focused primarily on 25(OH)D and its relation to obesity, T2DM, and/or CVDs, and 3) were published in peer-reviewed journals. The influences of key confounders such as age, gender, and ethnicity on any observed relations were also assessed. Due to the heterogeneity of study characteristics, only a narrative synthesis was undertaken. RESULTS Ethnic minorities had significantly higher rates of vitamin D insufficiency (25[OH]D <50 nmol/L; children 43.6-48.7% versus 10%; adults 30.3-53% versus 13.7-26%) than their white counterparts. None of the studies reported a prevalence of obesity stratified by ethnicity. There was evidence supporting links between vitamin D deficiency and obesity-related chronic diseases, with 14 of 14 studies reporting a statistically significant result with a measurement of obesity, four of five for T2DM, four of five for CVDs, and one of one for the metabolic syndrome. However, the strength of the association varied across ethnic groups depending on the index used to measure adiposity, T2DM, and CVDs. Because most of the included studies were cross-sectional and there were variations in outcome measurements, it was not possible to determine the relative contributions of obesity or vitamin D insufficiency to CVD risk and risk of T2DM or which is the initial driver It is possible both have a role to play. CONCLUSION Further research specific to migrant populations using randomized controlled trials are required to establish whether causal links between 25(OH)D and obesity-related chronic disease exist, and whether vitamin D supplementation could be valuable in the prevention or treatment of obesity-related diseases.

Associations between body mass index and health-related quality of life among Australian adults.

ObjectivesTo assess the relationship between body mass index (BMI) and health-related quality of life (HQoL), as measured by the Short Form Health Survey (SF-36) within a sample with broad population coverage.Subjects and methodsSurvey data incorporating the SF-36 questionnaire, height and weight were obtained from a nationally representative sample of 9,771 Australians aged 21 or older (4,649 men and 5,122 women). Linear multiple regression methods were employed to estimate the magnitude of association between BMI classes and HQoL variables, adjusting for disability and other covariates.ResultsLess than 1% of men and just 3.5% of women were classified as underweight while 52.2% of women and 65.9% of men were classified as overweight or obese. For all SF-36 health dimensions, people with BMI scores in the healthy range reported, on average, higher health-related HQoL scores than underweight and obese people, and HQoL scores decreased with the degree of obesity. Although overweight and obesity were associated with decreasing levels of both physical and emotional well-being, the deterioration in health status was significantly more evident in the physical than in the mental, social or emotional dimensions.ConclusionsLow and high BMIs were associated with decreasing levels of both physical and emotional well-being, but the deterioration in health status was more consistent in the physical than in other dimensions.

Food security measurement in cultural pluralism : missing the point or conceptual misunderstanding?

OBJECTIVE Food Security has become a global concern, yet its measurement has varied considerably across disciplines and countries. We examined the current discrepancies in the definitions of food security and propose a framework for understanding and measuring food security. METHODS This conceptual review draws from a range of works published in Medline and the gray literature to advance the understanding of food security concepts. We begin by examining the historical background of food security and then move on to examine its various definitions and interpret food through cultural lenses in terms of food access and utilization. We finish by examining various measurements and indicators of food security and reviewing implications for public health. RESULTS We argue that the reliance on coping strategies as surrogate measurements of food insecurity without taking into account the social, cultural, and political contexts in which they occur is misleading, and viewing food insecurity solely from a food access or availability perspective, without taking into account food utilization and asset creation as pillars of food security, paints an incomplete picture. Although this review does not claim to provide solutions to the discrepancies in the conceptual definition of food security, it attempts to highlights areas of concern and provide a way forward. CONCLUSION When coping strategies are used as an indicator of food insecurity, they need to be culturally relevant and focus tested, and together with objective measurements of nutritional outcomes, would allow policy makers to make evidence-based decisions to inform social and nutrition policies.

The relationship between family functioning and child and adolescent overweight and obesity: a systematic review.

There is mounting evidence that family functioning is linked to childhood overweight and obesity, and that both of these are associated with health-related behaviours and adverse health outcomes in children and adolescents. This paper systematically examines the peer-reviewed evidence regarding the relationship between child and adolescent overweight and obesity and family functioning. Peer-reviewed literature published between 1990 and 2011 hosted in Scopus, Pub Med or Psyc INFO were searched, in addition to the reference lists of included papers. Twenty-one studies met the selection criteria. Of the 17 identified cross-sectional and longitudinal studies, 12 reported significant associations between family functioning and childhood overweight and obesity. The instruments used to measure family functioning in the identified studies were heterogeneous. Poor family functioning was associated with increased risk of obesity and overweight in children and adolescents, and obese children and adolescents were more likely to come from families with poor family functioning. Aspects of family functioning which were associated with increased risk of child and adolescent obesity included poor communication, poor behaviour control, high levels of family conflict and low family hierarchy values. Half (2/4) of the identified intervention studies showed a significant relationship between family functioning and changes in child weight. The results demonstrate that family functioning is linked to obesity; however, higher level evidence and greater understanding of the mechanisms behind this relationship are required. The results indicate a need for a standardised family functioning measure applicable across populations. The results provide evidence of the value of considering family functioning in childhood obesity research and intervention.

Community-based study on knowledge, attitude and practice on the mode of transmission, prevention and treatment of the Buruli ulcer in Ga West District, Ghana

Buruli ulcer disease (BUD), a devastating tropical disease caused by Mycobacterium ulcerans, occurs in more than 80% of the administrative districts of Ghana. To elucidate community perceptions and understanding of the aetiology of BUD, attitudes towards Buruli patients and treatment‐seeking behaviours, we conducted a survey with 504 heads of households and seven focus group discussions in Ga West District, Ghana. Although 67% of participants regarded BUD as a health problem, 53% did not know its cause. Sixteen per cent attributed the cause to drinking non‐potable water, 8.1% mentioned poor personal hygiene or dirty surroundings, and 5.5% identified swimming or wading in ponds as a risk factor. About 5.2% thought that witchcraft and curses cause BUD, and 71.8% indicated that BU sufferers first seek treatment from herbalists and only refer to the hospital as a last resort. The main reasons were prospects of prolonged hospital stay, cost of transport, loss of earnings and opportunity associated with parents attending their childrens hospitalization over extended period, delays in being attended by medical staff, and not knowing the cause of the disease or required treatment. The level of acceptance of BUD sufferers was high in adults but less so in children. The challenge facing health workers is to break the vicious cycle of poor medical outcomes leading to poor attitudes to hospital treatment in the community. Because herbalists are often the first people consulted by those who contract the disease, they need to be trained in early recognition of the pre‐ulcerative stage of Buruli lesions.

Vitamin D supplementation to reduce depression in adults: Meta-analysis of randomized controlled trials

OBJECTIVES The aim of this study was to estimate the weighted mean effect of vitamin D supplementation in reducing depressive symptoms among individuals aged ≥18 y diagnosed with depression or depressive symptoms. METHODS A meta-analysis of randomized controlled trials (RCTs) in which vitamin D supplementation was used to reduce depression or depressive symptoms was conducted. Databases MEDLINE, EMBASE, psych INFO, CINAHL plus, and the Cochrane library were searched from inception to August 2013 for all publications on vitamin D and depression regardless of language. The search was further updated to May 2014 to include newer studies being published. Studies involving individuals aged ≥18 y who were diagnosed with depressive disorder based on both the Diagnostic and Statistical Manual of Mental Disorders or other symptom checklist for depression were included. Meta-analysis was performed using random effects model due to differences between the individual RCTs. RESULTS The analysis included nine trials with a total of 4923 participants. No significant reduction in depression was seen after vitamin D supplementation (standardized mean difference = 0.28; 95% confidence interval, -0.14 to 0.69; P = 0.19); however, most of the studies focused on individuals with low levels of depression and sufficient serum vitamin D at baseline. The studies included used different vitamin D doses with a varying degree of intervention duration. CONCLUSIONS Future RCTs examining the effect of vitamin D supplementation among individuals who are both depressed and vitamin D deficient are needed.

Urbanisation, urbanicity, and health: a systematic review of the reliability and validity of urbanicity scales

BackgroundDespite a plethora of studies examining the effect of increased urbanisation on health, no single study has systematically examined the measurement properties of scales used to measure urbanicity. It is critical to distinguish findings from studies that use surrogate measures of urbanicity (e.g. population density) from those that use measures rigorously tested for reliability and validity. The purpose of this study was to assess the measurement reliability and validity of the available urbanicity scales and identify areas where more research is needed to facilitate the development of a standardised measure of urbanicity.MethodsDatabases searched were MEDLINE with Full Text, CINAHL with Full Text, and PsycINFO (EBSCOhost) as well as Embase (Ovid) covering the period from January 1970 to April 2012. Studies included in this systematic review were those that focused on the development of an urbanicity scale with clearly defined items or the adoption of an existing scale, included at least one outcome measure related to health, published in peer-reviewed journals, the full text was available in English and tested for validity and reliability.ResultsEleven studies met our inclusion criteria which were conducted in Sri Lanka, Austria, China, Nigeria, India and Philippines. They ranged in size from 3327 to 33,404 participants. The number of scale items ranged from 7 to 12 items in 5 studies. One study measured urban area socioeconomic disadvantage instead of urbanicity. The emerging evidence is that increased urbanisation is associated with deleterious health outcomes. It is possible that increased urbanisation is also associated with access and utilisation of health services. However, urbanicity measures differed across studies, and the reliability and validity properties of the used scales were not well established.ConclusionThere is an urgent need for studies to standardise measures of urbanicity. Longitudinal cohort studies to confirm the relationship between increased urbanisation and health outcomes are urgently needed.

Intergenerational Differences in Food, Physical Activity, and Body Size Perceptions Among African Migrants

We assessed intergenerational differences in food, physical activity, and body size perceptions among refugees and migrants from the Horn of Africa living in Victoria, Australia. We used a qualitative design and obtained data from 48 participants (18 individual interviews; 3 semistructured focus groups). Three major themes emerged: (a) food and physical activity, (b) preference of body size and social expectations, and (c) perceived consequences of various body sizes. For parents, large body size was perceived to equate with being beautiful and wealthy; slimness was associated with chronic illness and poverty. Parents adopted strategies that promoted weight gain in children. These included tailored food practices and restricting children’s involvement in physical activity. For young people, slimness was the ideal body size endorsed by their peers, and they adopted strategies to resist parental pressure to gain weight. Obesity-prevention programs in this subpopulation need to adopt a multigenerational approach.