Family average income and body mass index above the healthy weight range among urban and rural resicents in regional Mainland China

Objective: To explore the relationship between family average income (FAI; an index of socio-economic status) and body mass index (BMI; a widely used, inexpensive indicator of weight status) above the healthy weight range in a region of Mainland China. Design: Population-based cross-sectional study, conducted between October 1999 and March 2000 on a sample of regular local residents aged 35 years or older who were selected by random cluster sampling. Setting: Forty-five administrative villages selected from three urban districts and two rural counties of Nanjing municipality, Mainland China, with a regional population of 5.6 million. Subjects: In total, 29 340 subjects participated; 67.7% from urban and 32.3% from rural areas; 49.8% male and 50.2% female. The response rate among eligible participants was 90.1%. Results: The proportion of participants classified as overweight was 30.5%, while 7.8% were identified as obese. After adjusting for possible confounding variables (age, gender, area of residence, educational level, occupational and leisure-time physical activity, daily vegetable consumption and frequency of red meat intake), urban participants were more likely to be overweight or obese relative to their rural counterparts, more women than men were obese, and participants in the lowest FAI tertile were the least likely to be above the healthy weight range. Conclusions: The proportion of adults with BMI above the healthy weight range was positively related to having a higher socio-economic status (indexed by FAI) in a regional Chinese population.

Trends in body mass index according to educational attainment for urban Australian adults between 1980 and 2007

BackgroundWe have previously demonstrated that between the years 1980 and 2000, the mean body mass index (BMI) of the urban Australian population increased, with greater increases observed with increasing BMI. The current study aimed to quantify trends over time in BMI according to education between 1980 and 2007.MethodsWe compared data from the 1980, 1983 and 1989 National Heart Foundation Risk Factor Prevalence Studies, 1995 National Nutrition Survey, 2000 Australian Diabetes, Obesity and Lifestyle Study and the 2007 National Health Survey. For survey comparability, analyses were restricted to urban Australian residents aged 25-64 years. BMI was calculated from measured height and weight. The education variable was dichotomised at completion of secondary school. Four age-standardised BMI indicators were compared over time by sex and education: mean BMI, mean BMI of the top five percent of the BMI distribution, prevalence of obesity (BMI⩾30 kg/m(2)), prevalence of class II(+) obesity (BMI⩾35 kg/m(2)).ResultsBetween 1980 and 2007, the mean BMI among men increased by 2.5 kg/m(2) and 1.7 kg/m(2) for those with low and high education levels, respectively, corresponding to increases in obesity prevalence of 20(from 12% to 32%) and 11(10% to 21%) %-points. Among women mean BMI increased by 2.9 kg/m(2) and 2.4 kg/m(2) for those with low and high education levels respectively, corresponding to increases in obesity prevalence of 16(12% to 28%) and 12(7% to 19%) %-points. The prevalence of class II(+) obesity among men increased by 9(1% to 10%) and 4(1% to 5%) %-points for those with low and high education levels, and among women increased by 8(4% to 12%) and 4(2% to 6%) %-points. Absolute and relative differences between education groups generally increased over time.ConclusionsEducational differences in BMI have persisted among urban Australian adults since 1980 without improvement. Obesity prevention policies will need to be effective in those with greatest socio-economic disadvantage if we are to equitably and effectively address the population burden of obesity and its corollaries.International Journal of Obesity accepted article preview online, 16 March 2015. doi:10.1038/ijo.2015.27.

Trends in the skewness of the body mass index distribution among urban Australian adults, 1980 to 2007

Purpose We analyzed the changes in the body mass index (BMI) distribution for urban Australian adults between 1980 and 2007.

Methods We used data from participants of six consecutive Australian nation-wide surveys with measured weight and height between 1980 and 2007. We used quantile regression to estimate mean BMI (for percentiles of BMI) and prevalence of severe obesity, modeled by natural splines in age, date of birth, and survey date.

Results Since 1980, the right skew in the BMI distribution for Australian adults has increased greatly for men and women, driven by increases in skew associated with age and birth cohort/period. Between 1980 and 2007, the average 5-year increase in BMI was 1 kg/m2 (0.8) for the 95th percentile of BMI in women (men). The increase in the median was about a third of this, and for the 10th percentile, a fifth of this. We estimated that for the cohort born in 1960 around 31% of men and women were obese by age 50 years compared with 11% of the 1930 birth cohort.

Conclusions There have been large increases in the right skew of the BMI distribution for urban Australian adults between 1980 and 2007, and birth cohort effects suggests similar increases are likely to continue.

Urban amphibian assemblages as metacommunities

1. Urban ecosystems are expanding throughout the world, and urban ecology is attracting increasing research interest. Some authors have questioned the value of existing ecological theories for understanding the processes and consequences of urbanization.
2. In order to assess the applicability of metacommunity theory to urban systems, I evaluated three assumptions that underlie the theory – the effect of patch area, the effect of patch isolation, and species–environment relations – using data on assemblages of pond-breeding amphibians in the Greater Melbourne area of Australia. I also assessed the relative impact of habitat fragmentation, habitat isolation, and changes to habitat quality on these assemblages.
3. Poisson regression modelling provided support for an important increase in species richness with patch area (pond size) and a decrease in species richness with increasing patch isolation, as measured by surrounding road cover. Holding all other variables constant, species richness was predicted to be 2·8–5·5 times higher at the largest pond than at the smallest, while the most isolated pond was predicted to have 12–19% of the species richness of the least isolated pond. Thus, the data were consistent with the first two assumptions of metacommunity theory evaluated.
4. The quality of habitat at a pond was also important, with a predicted 44–56% decrease in the number of species detected at ponds with a surrounding vertical wall compared with those with a gently sloping bank. This demonstrates that environmental differences between habitat patches were also influencing amphibian assemblages, providing support for the species-sorting and/or mass-effect perspectives of metacommunity theory.
5. Without management intervention, urbanization may lead to a reduction in the number of amphibian species persisting in urban ponds, particularly where increasing isolation of ponds by roads and associated infrastructure reduces the probability of re-colonization following local extinction.

Family average income and diagnosed Type 2 diabetes in urban and rural residents in regional mainland China.

Aims: To explore the relationship between family average income (FAI; an index of socio-economic status) and Type 2 diabetes in a region of mainland China. Methods: Population-based cross-sectional study, conducted between October 2000 and March 2001 in administrative villages (n = 45) randomly selected from three urban districts and two rural counties of NanJing municipality, mainland China, with a regional population of 5.6 million. Participants were all local residents aged ≥ 35 years old (n = 29 340); 67.7% from urban areas, 32.3% from rural areas, 49.8% male and 50.2% female. Results: The response rate of eligible participants was 90.1%. The overall prevalence of self-reported Type 2 diabetes was 1.9%. After adjustment for possible confounding variables (age, gender, area of residence, body mass index, educational level, smoking status, occupational and leisure-time physical activity), participants in the higher and middle FAI categories were more than twice as likely to have Type 2 diabetes as those in the lower FAI category. Conclusions: The prevalence of Type 2 diabetes is positively related to socio-economic status (indexed by FAI) in Chinese at the population level. After controlling for potential confounding factors, people in higher socio-economic status groups are more likely to have Type 2 diabetes. These associations are consistent with other effects of epidemiological transition and identify a need for preventive initiatives.

Landscape influences on avian density in urban remnant vegetation

The management of urban environments is an increasingly important issue on an international scale as humans emigrate from rural areas to cities. Designing cities that can sustain mass human expansion while maintaining biodiversity is becoming an increasingly complex challenge for land managers. This is largely due to the lack of knowledge on how urbanization impacts upon biodiversity. Our previous research has highlighted the importance of urban remnant vegetation for avian diversity, but also suggested that landscape scale influences may have considerable impacts on the ability for a remnant to sustain species. We have since conducted a study examining avian diversity in 38 urban remnants ranging in size from 5ha to 107ha. These sites vary in relation to the quality of vegetation in the patch and their level of isolation from other remnant patches. This talk discusses the relative influences of remnant patch size, vegetation quality and isolation on avian diversity in urban remnant vegetation. We discuss how the findings of this research could be applied to managing avian diversity in the urban landscape.

Urban living and obesity : is it independent of its population and lifestyle characteristics?

OBJECTIVES: Living in an urban area influences obesity. However, little is known about whether this relationship is truly independent of, or merely mediated through, the demographic, socio-economic and lifestyle characteristics of urban populations. We aimed to identify and quantify the magnitude of this relationship in a Sri Lankan population.

METHODS: Cross-sectional study of adults aged 20-64 years representing the urban (n = 770) and rural (n = 630) populations, in the district of Colombo in 2004. Obesity was measured as a continuous variable using body mass index (BMI). Demographic, socio-economic and lifestyle factors were assessed. Gender-specific multivariable regression models were developed to quantify the independent effect of urban/ rural living and other variables on increased BMI.

RESULTS: The BMI (mean; 95% confidence interval) differed significantly between urban (men: 23.3; 22.8-23.8; women: 24.2; 23.7-24.7) and rural (men: 22.3; 21.9-22.7; women: 23.2; 22.7-23.7) sectors (P < 0.01). The observed association remained stable independently of all other variables in the regression models among both men (coefficient = 0.64) and women (coefficient = 0.95). These coefficients equated to 2.2 kg weight for the average man and 1.7 kg for the average woman. Other independent associations of BMI were with income (coefficient = 1.74), marital status (1.48), meal size (1.53) and religion (1.20) among men, and with age (0.87), marital status (2.25) and physical activity (0.96) among women.

CONCLUSIONS: Urban living is associated with obesity independently of most other demographic, socio-economic and lifestyle characteristics of the population. Targeting urban populations may be useful for consideration when developing strategies to reduce the prevalence of obesity.

ID scanning, the media and the politics of urban surveillance in an Australian regional city

Computerised ID scanning technologies have permeated many urban night-time economies in Australia, the United States, Canada and the United Kingdom. This paper documents how one media organisation’s overt and tacit approval of ID scanners helped to normalise this form of surveillance as a precondition of entry into most licensed venues in the Australian city of Geelong. After outlining how processes of governance “from above” and “from below” interweave to generate distinct political and media demands for strategies to prevent localised crime problems, a chronological reconstruction of media reports over a three-and-a half year period demonstrates how ID scanning became the centrepiece of a holistic reform strategy to combat alcohol-related violence in this nightclub precinct. Several discursive techniques helped to normalise this “technological fix”, while suppressing critical discussion of viable concerns over information privacy, data security and system networking. These
included pairing reports of an initial “signal crime” with examples of “virtual victimhood” to stress the urgency of a radical surveillance-based response, which was supported by anecdotal statements from key “primary definers” highlighting the success of this initiative in targeting a wider population of antisocial “others”. The implications of these reporting practices are discussed in light of the media’s central role in reforming the Geelong night-time economy and broader trends in using novel surveillance technologies to combat urban crime problems at the expense of alternative measures that protect individual liberty.

Zonal banning and public order in urban Australia

In recent years, Australian governments of various ideological persuasions at local, state and territory and federal levels have introduced a range of zonal governing techniques to manage the flow of people in urban spaces. Zonal governance involves the identification and formal declaration of a specific urban geographic region to enable police and security personnel to deploy special powers and allied forms of surveillance technologies as a supplement to their conventional public order maintenance functions.

Despite the impetus towards open flows or movement within sovereign territories or larger territorial groupings, such as the European Union, considerable governmental effort has been directed towards the use of new forms of criminal law to re-territorialize urban space through new administrative, property law and regulatory measures. These low-level spatial demarcations introduce various supplementary police powers and discretionary procedures that enhance surveillance within a declared area to increase the level of contemporary urban security. Of particular concern is the legal right to ban or exclude “undesirable” individuals and groups from entering or using certain designated urban zones, to prevent antisocial or violent behavior usually associated with alcohol consumption.

To date, most discussion of the impact of banning and related surveillance measures focuses on illegal migration through ports of entry into sovereign nations and the commensurate burdens this creates for both citizens and non-citizens to authenticate their movements at national geographic borders. This logic is permeating more localized forms of regulation adopted by Australian local and mid-tier state and territory governments to control the movement of people in and out of major event sites and in the urban night-time economy.

A survey of recent reforms in the state of Victoria reveals how this new logic of mass-surveillance aims to promote greater levels of urban security while reshaping the conventional order maintenance functions of both the public and private police. This chapter describes these procedures and their impact in sanctioning the efficient screening of people to promote order in specific zones within the contemporary Australian urban environment, at the expense of more progressive and inclusive crime prevention initiatives. We focus on two exemplars of the intensification of surveillance through zonal governance techniques: ‘major events’ and ‘designated alcohol zones’.

Peak oxygen uptake of 12-18-year-old boys living in a densely populated urban environment

The purposes of this study were to provide data on the peak Vo 2 of 12-18-year-old boys from Hong Kong, a densely populated urban environment; to compare these data with those for other similarly aged populations; and to examine the correlations between peak Vo 2 and various anthropometric parameters of this group. A stratified, random sample of 86 ethnic Chinese boys had their peak Vo 2 determined using an on-line gas analysis system during incremental, treadmill running. The mean peak 17o2 of the boys was 2.7 SD 0.44 1- rain - 1 or, when expressed in relation to body mass, 52.0 SD 5-8 ml- kg- 1. min - 1. Peak Vo 2 (1. min - 1) was significantly correlated with body mass (r = 0.72, p < 0.001, age (r = 0.49, p < 0.001) and height (r = 0.71, p = 0-001). Peak Vo 2 (ml 'kg- 1. min- 1) showed no correlation with age or height. These data suggest that this population group has peak Vo 2 values very similar to those observed in boys from most other population groups.

Perceptions of subjective economic well-being and support for market reform among China's urban population

This article examines whether subjective economic assessments have any impact on support for further market reforms among China's urban population, utilising a large survey of 10,716 people across 32 cities. The effect of subjective economic well-being on support for market reforms is an important issue for the Chinese government as it seeks to sell the benefits of increased globalisation and marketisation to its citizens. Our main finding is that people's assessment of the overall economic situation helps to explain support for market reform, although the relationship is weak, while people's assessment of their own economic circumstances does not influence support for reform. The findings are compared with those of similar studies for Central and Eastern Europe. © 2005 Centre for Research into Post-Communist Economies.

Obesity in adults: an emerging problem in urban areas of Ho Chi Minh City, Vietnam

OBJECTIVE: To assess the prevalence of overweight, obesity and underweight among Vietnamese adults living in urban areas of Ho Chi Minh City (HCMC), Vietnam. DESIGN: This cross-sectional survey was conducted in the local health stations of 30 randomly selected wards, which represent all 13 urban districts of HCMC, over a period of 2 months from March to April 2004. SUBJECTS: A total of 1488 participants aged 20-60 years completed the interview, physical examination and venous blood collection. MEASUREMENTS: Anthropometric measurements of body weight, height, waist and hip circumference were taken to construct indicators of adiposity including body mass index (BMI), waist circumference, and waist-to-height and waist-to-hip ratios. Both systolic and diastolic blood pressure and biochemical indicators of cardiovascular disease and type II diabetes risk (lipid profile and fasting blood glucose) were also measured. RESULTS: The age and sex standardized prevalence of overweight and obesity using Asian specific BMI cutoffs of 23.0 and 27.5 kg/m2 was 26.2 and 6.4%, respectively. The prevalence of overweight and obesity was slightly higher in females (33.6%) than males (31.6%), and progressively increased with age. The age and sex-standardized prevalence of underweight (BMI <18.5 kg/m2) among Vietnamese adults living in HCMC was 20.4%. The prevalence was slightly higher in males (22.0%) than in females (18.9%), and there was a much higher prevalence in all underweight categories in younger women than in men but this was reversed for older men. CONCLUSION: The adult population in HCMC Vietnam is in an early 'nutrition transition' with approximately equal prevalence of low and high BMI. The prevalence of overweight and obesity of Vietnamese urban adults was lower than that reported for other east and southeast Asian countries.

Population, behavioural and physiological responses of an urban population of black swans to an intense annual noise event

Wild animals in urban environments are exposed to a broad range of human activities that have the potential to disturb their life history and behaviour. Wildlife responses to disturbance can range from emigration to modified behaviour, or elevated stress, but these responses are rarely evaluated in concert. We simultaneously examined population, behavioural and hormonal responses of an urban population of black swans Cygnus atratus before, during and after an annual disturbance event involving large crowds and intense noise, the Australian Formula One Grand Prix. Black swan population numbers were lowest one week before the event and rose gradually over the course of the study, peaking after the event, suggesting that the disturbance does not trigger mass emigration. We also found no difference in the proportion of time spent on key behaviours such as locomotion, foraging, resting or self-maintenance over the course of the study. However, basal and capture stress-induced corticosterone levels showed significant variation, consistent with a modest physiological response. Basal plasma corticosterone levels were highest before the event and decreased over the course of the study. Capture-induced stress levels peaked during the Grand Prix and then also declined over the remainder of the study. Our results suggest that even intensely noisy and apparently disruptive events may have relatively low measurable short-term impact on population numbers, behaviour or physiology in urban populations with apparently high tolerance to anthropogenic disturbance. Nevertheless, the potential long-term impact of such disturbance on reproductive success, individual fitness and population health will need to be carefully evaluated.

Trends in BMI of urban Australian adults, 1980-2000

OBJECTIVE: To analyse changes in the distribution of BMI in Australia between 1980 and 2000. DESIGN: Data were from the 1980, 1983 and 1989 National Heart Foundation Risk Factor Prevalence Study, the 1995 National Nutrition Survey and the 1999/2000 Australian Diabetes, Obesity and Lifestyle Study. Survey participants were aged 25-64 years and resident in Australian capital cities. BMI was calculated as weight divided by height squared (kg/m2), where weight and height were measured using standard procedures. RESULTS: Mean BMI was higher in 2000 than 1980 in all sex and age groups. The age-adjusted increase was 1.4 kg/m2 in men and 2.1 kg/m2 in women. The BMI distribution shifted rightwards for all sex and age groups and became increasingly right-skewed. The change between 1980 and 2000 ranged from a decrease of 0.04 kg/m2 at the lower end of the distribution for men aged 25-34 years to an increase of 7.4 kg/m2 at the higher end for women aged 55-64 years. While the prevalence of obesity (BMI >or= 30 kg/m2) doubled, the prevalence of obesity class III (BMI >or= 40 kg/m2) increased fourfold. CONCLUSIONS: BMI in urban Australian adults has increased and its distribution has become increasingly right-skewed. This has resulted in a large increase in the prevalence of obesity, particularly the more severe levels of obesity. It will be important to monitor changes in the different classes of obesity and the extent to which obesity interventions both shift the BMI distribution leftwards and decrease the skew of the distribution.

Prevalence of underweight, overweight and obesity in urban Hanoi, Vietnam

This study aims to assess the prevalence of underweight, overweight and obesity among adults in urban Hanoi, Vietnam; and compare these results to previous estimates among adults in urban Ho Chi Minh City. Survey participants were residents in urban Hanoi, Vietnam and aged between 25-74 years. Data from a cross-sectional biomedical survey conducted in 2004 were collected; which included a questionnaire, physical examination and blood tests. The age-standardised prevalence of overweight and obesity in 2004, using Asian-specific body mass index cut-offs, were 28.6% and 2.1%, respectively. The prevalence of overweight/obesity (combined) was similar in males (29.7%) and females (31.5%), and generally increased with age. The prevalence of overweight/obesity was considerably lower if the standard cut-off values of the World Health Organization were used. The age-standardised prevalence of underweight was 13.3%; and that of 'increased risk'/'substantially increased risk' waist circumference (combined) was 27.9% in males and 25.7% in females, respectively. Almost one in three adults in urban Hanoi were overweight or obese in 2004 and more than one in ten were underweight (based on Asian-specific cut-off values). This prevalence of overweight/obesity is similar to that for adults in urban Ho Chi Minh City, but the prevalence of underweight is lower. While low body weight remains a concern, overweight and obesity are an increasing problem for urban Vietnamese adults.