Objectively measured waist circumference is most strongly associated in father-boy and mother-girl dyads in a large nationally representative sample of New Zealanders.

BACKGROUND: The prevalence of children with elevated weight or obesity is concerning for public health due to associated comorbidities. This study investigates associations between parental adiposity, physical activity (PA), fruit and vegetable consumption, and child adiposity and moderation by both child and parent gender. METHODS: Cross-sectional nationally representative data from the New Zealand Health Survey were pooled for the years 2013/14-2016/17. Parent and child surveys were matched resulting in 13,039 child (2-14 years) and parent (15-70 years) dyads. Parent and child, height (cm), weight (kg) and waist circumference (WC) were measured objectively. Height and weight were used to calculate BMI. Linear regression, accounting for clustered samples (b [95% CI]) investigated associations between parental characteristics and child BMI z-score and WC. Interactions and stratification were used to investigate effect moderation by parent gender, child gender, and parent adiposity. RESULTS: Parental PA and fruit and vegetable consumption were unrelated to child adiposity. Overall, higher parent BMI was related to a higher child BMI z-score (b = 0.047 [0.042, 0.052]) and higher parental WC was related to a higher child WC (0.15 [0.12, 0.17]). A three-way interaction revealed no moderation by parent gender, child gender, and parent BMI for child BMI z-score ((b = 0.005 [-0.017, 0.027], p = 0.318). However, a three-way interaction revealed moderation by parent gender, child gender, and parent WC for child WC (b = 0.13 [0.05, 0.22]). The slightly stronger associations were seen between father-son WC (b = 0.20 [0.15, 0.24]) and mother-daughter WC (b = 0.19 [0.15, 0.22]). CONCLUSIONS: The findings are highly relevant for those wishing to understand the complex relationships between child-parent obesity factors. Findings suggest that family environments should be a key target for obesity intervention efforts and show how future public health interventions should be differentiated to account for both maternal and paternal influences on child adiposity.

Unhealthy environments are associated with adverse mental health and psychological distress: Cross-sectional evidence from nationally representative data in New Zealand.

This study combines data on the location of health-constraining 'bads' (i: fast-food outlets, ii: takeaway outlets, iii: dairy outlets and convenience stores, iv: alcohol outlets, and v: gaming venues) and health-promoting 'goods' (i: green spaces, ii: blue spaces, iii: physical activity facilities, and iv: fruit and vegetable outlets) into a nationwide Healthy Living Index. This was applied to pooled (2015/16-2017/18) nationally representative New Zealand Health Survey data, with mental health conditions (depression, bipolar, and anxiety) and psychological distress as population-level outcomes. Mental health was associated with proximity to environmental 'goods' and 'bads'. Compared to those individuals who reside within the unhealthiest environments, there was a steady reduction in the odds of adverse mental health outcomes and psychological distress as the environment became more health-promoting.

Painting a picture of trans-Tasman mortality.

OBJECTIVES: The determinants of health and mortality inequalities in New Zealand and Australia have been subjected to research, with the influence of a range of socio-economic and demographic influences (deprivation, social class, ethnicity) receiving notable attention. Both countries are considered privileged, positioned amongst the world leaders in rankings of mortality and life expectancy. This paper reports on observed rates of mortality and views how the countries have fared over time with respect to one another. STUDY DESIGN, OBSERVATIONAL, METHODS: This study derives comparable rates of mortality for both New Zealand and Australia, disaggregated by age and sex for the time period 1948-2008. The age-standardised rates are visualised using the Lexis mapping software program, showing the relative differences between the countries over time whilst simultaneously highlighting age, period and cohort effects. RESULTS: Relative to Australia, New Zealand had advantageous rates of mortality across almost all age groups between the years 1948 and 1980 (approximately). For both sexes, a dramatic reversal of fortunes in New Zealand has followed relative to Australia. For example, for younger males in New Zealand, the reversal is startling. Over the time period observed, males aged 10-20 years in New Zealand have moved from an advantageous position of having a mortality rate 20% lower than Australia to a relative position of 50% higher. CONCLUSIONS: The social and economic forces in both New Zealand and Australia which may have driven the divergence require further scrutiny. It is argued here, that the changing fortunes of the populations are linked to the process of selective migration and the large-scale population movements between the countries facilitated by the Trans-Tasman Travel Arrangement. These findings have important implications for policy formation and service planning, if the inequality in mortality between the areas of study is to be addressed.

Exploring the feasibility of linking historical air pollution data to the Christchurch Health and Development study: A birth cohort study in Aotearoa, New Zealand.

Spatial life course epidemiological approaches offer promise for prospectively examining the impacts of air pollution exposure on longer-term health outcomes, but existing research is limited. An essential aspect, often overlooked is the comprehensiveness of exposure data across the lifecourse. The primary objective was to meticulously reconstruct historical estimates of air pollution exposure to include prenatal exposure as well as annual exposure from birth to 10 years (1977-1987) for each cohort member. We linked these data from a birth cohort of 1,265 individuals, born in Aotearoa/New Zealand in mid-1977 and studied to age 40, to historical air pollution data to create estimates of exposure from birth to 10 years (1977-1987). Improvements in air quality over time were found. However, outcomes varied by demographic and socioeconomic factors. Future research should examine how inequitable air pollution exposure is related to health outcomes over the life course.

An ecological study investigating the association between access to urban green space and mental health.

OBJECTIVES: This study aims to find whether proximity to urban green spaces is associated with human mental health. STUDY DESIGN: A cross-sectional examination of the relationship between access to urban green spaces and counts of anxiety/mood disorder treatments amongst residents (aged 15 years and over) in Auckland City, New Zealand. METHODS: Anxiety/mood disorder treatment counts by three age groups were aggregated to 3149 small area units in Auckland. Six measures of green space access were derived using GIS techniques involving total green spaces and useable green spaces. Negative binomial regression models have been fitted to test the relationship between access to green space and area-level anxiety/mood disorder treatment counts, adjusted for age and area-level deprivation. RESULTS: Anxiety/mood disorder treatment counts were associated with three green space measures. The proportion of both total and useable green space within 3 km and distance to nearest useable green space all indicated a protective effect of increased access to green space against anxiety/mood disorder treatment counts. Access to total and useable green space within 300 m did not exhibit significant associations. CONCLUSION: This study found that decreased distance to useable green space and increased proportion of green space within the larger neighbourhood were associated with decreased anxiety/mood disorder treatment counts in an urban environment. This suggests the benefits of green space on mental health may relate both to active participation in useable green spaces near to the home and observable green space in the neighbourhood environment.

Role of physical activity in the relationship between urban green space and health.

OBJECTIVES: Local availability of green space has been associated with a wide range of health benefits. Possible causative mechanisms underpinning the green space and health relationship include the provision of physical activity opportunities, the stress-relieving effects of nature and the facilitation of social contacts. This study sought to investigate whether urban green space was related to individual-level health outcomes, and whether levels of physical activity were likely to be a mediating factor in any relationships found. STUDY DESIGN: Cross-sectional analysis of anonymized individual health survey responses. METHODS: Neighbourhood-level green space availability was linked to 8157 respondents to the New Zealand Health Survey 2006/07 on the basis of their place of residence. Adjusted multilevel models were constructed for four health outcomes which are plausibly related to green space via physical activity: cardiovascular disease; overweight; poor general health; and poor mental health (Short Form 36). RESULTS: The greenest neighbourhoods had the lowest risks of poor mental health [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.66-1.00]. Cardiovascular disease risk was reduced in all neighbourhoods with >15% green space availability (e.g. OR 0.80, 95% CI 0.64-0.99 for those with 33-70% green space), However, a dose-response relationship was not found. Green space availability was not related to overweight or poor general health. Overall, levels of physical activity were higher in greener neighbourhoods, but adjustment for this only slightly attenuated the green space and health relationships. CONCLUSIONS: Neighbourhood green space was related to better cardiovascular and mental health in a New Zealand Health Survey, independent of individual risk factors. Although physical activity was higher in greener neighbourhoods, it did not fully explain the green space and health relationship.

Changing epidemiological trends of legionellosis in New Zealand, 1979-2009.

This study evaluated the spatio-temporal variation of Legionella spp. in New Zealand using notification and laboratory surveillance data from 1979 to 2009 and analysed the epidemiological trends. To achieve this we focused on changing incidence rates and occurrence of different species over this time. We also examined whether demographic characteristics such as ethnicity may be related to incidence. The annual incidence rate for laboratory-proven cases was 2·5/100,000 and 1·4/100,000 for notified cases. Incidence was highest in the European population and showed large geographical variations between 21 District Health Boards. An important finding of this study is that the predominant Legionella species causing disease in New Zealand differs from that found in other developed countries, with about 30-50% of cases due to L. longbeachae and a similar percentage due to L. pneumophila for any given year. The environmental risk exposure was identified in 420 (52%) cases, of which 58% were attributed to contact with compost; travel was much less significant as a risk factor (6·5%). This suggests that legionellosis has a distinctive epidemiological pattern in New Zealand.

Health-promoting and health-constraining environmental features and physical activity and sedentary behaviour in adolescence: a geospatial cross-sectional study.

The environment may be an important influence on adolescent behaviour. We combined accelerometry and global positioning system data to investigate how the environment was related to physical activity and sedentary behaviour. Adolescents spent most of their time in very close proximity to a range of both health-promoting and health-constraining features. Several associations were detected between time spent in areas with the greatest access to health-promoting features and reduced sedentary time and less travel time by motor vehicle. The environment may contribute to the variation in adolescent activity behaviour.

Progress Towards Using Linked Population-Based Data For Geohealth Research: Comparisons Of Aotearoa New Zealand And The United Kingdom.

Globally, geospatial concepts are becoming increasingly important in epidemiological and public health research. Individual level linked population-based data afford researchers with opportunities to undertake complex analyses unrivalled by other sources. However, there are significant challenges associated with using such data for impactful geohealth research. Issues range from extracting, linking and anonymising data, to the translation of findings into policy whilst working to often conflicting agendas of government and academia. Innovative organisational partnerships are therefore central to effective data use. To extend and develop existing collaborations between the institutions, in June 2019, authors from the Leeds Institute for Data Analytics and the Alan Turing Institute, London, visited the Geohealth Laboratory based at the University of Canterbury, New Zealand. This paper provides an overview of insight shared during a two-day workshop considering aspects of linked population-based data for impactful geohealth research. Specifically, we discuss both the collaborative partnership between New Zealand's Ministry of Health (MoH) and the University of Canterbury's GeoHealth Lab and novel infrastructure, and commercial partnerships enabled through the Leeds Institute for Data Analytics and the Alan Turing Institute in the UK. We consider the New Zealand Integrated Data Infrastructure as a case study approach to population-based linked health data and compare similar approaches taken by the UK towards integrated data infrastructures, including the ESRC Big Data Network centres, the UK Biobank, and longitudinal cohorts. We reflect on and compare the geohealth landscapes in New Zealand and the UK to set out recommendations and considerations for this rapidly evolving discipline.

Close proximity to alcohol outlets is associated with increased crime and hazardous drinking: Pooled nationally representative data from New Zealand.

This nationwide study investigated the relationship between proximity to alcohol outlets (off-licence, on-licence, and other-licence) and two adverse outcomes; hazardous drinking and crime (common assault, non-aggravated sexual assault, aggravated sexual assault, and tobacco and liquor offences). After adjustment for important individual- and area-level factors, close proximity to alcohol outlets was associated with increased risk of hazardous drinking, with strong associations for on-licence outlets. Proximity alcohol outlets was also strongly associated with all crime outcomes, often with a dose-response relationship. Nationally representative New Zealand data showed that close proximity to alcohol outlets was associated with increased crime and hazardous drinking.

Establishing links between air quality and health: searching for the impossible?

Traditional approaches in environmental spatial epidemiology have relied on assessing postulated links between environmental pollution and ill health, often as a response to a perceived public health problem; clearly it may be necessary to go beyond this stage in order to establish the nature of potential causal mechanisms. Different disciplines approach this issue in different ways. Many toxicologists favour approaches based on air quality monitoring, where raised levels of candidate pollutants may subsequently generate hypotheses about adverse health effects. Epidemiologists, however, assess the health of a population and then look for an associated cause. This paper suggests that neither approach is completely satisfactory and that a combination of both is needed. If spatially referenced data are available for both health status and air quality, then geographical analysis is needed to examine possible links, by using techniques such as atmospheric dispersion modelling and Geographical Information Systems. We discuss the benefits and constraints of these approaches, using empirical examples of environmental epidemiology studies for northern England. Taking into account the problems involved in such studies, allied to the high costs incorporated, the paper asks the question: Are we searching for the impossible?

A regression-based method for mapping traffic-related air pollution: application and testing in four contrasting urban environments.

Accurate, high-resolution maps of traffic-related air pollution are needed both as a basis for assessing exposures as part of epidemiological studies, and to inform urban air-quality policy and traffic management. This paper assesses the use of a GIS-based, regression mapping technique to model spatial patterns of traffic-related air pollution. The model--developed using data from 80 passive sampler sites in Huddersfield, as part of the SAVIAH (Small Area Variations in Air Quality and Health) project--uses data on traffic flows and land cover in the 300-m buffer zone around each site, and altitude of the site, as predictors of NO2 concentrations. It was tested here by application in four urban areas in the UK: Huddersfield (for the year following that used for initial model development), Sheffield, Northampton, and part of London. In each case, a GIS was built in ArcInfo, integrating relevant data on road traffic, urban land use and topography. Monitoring of NO2 was undertaken using replicate passive samplers (in London, data were obtained from surveys carried out as part of the London network). In Huddersfield, Sheffield and Northampton, the model was first calibrated by comparing modelled results with monitored NO2 concentrations at 10 randomly selected sites; the calibrated model was then validated against data from a further 10-28 sites. In London, where data for only 11 sites were available, validation was not undertaken. Results showed that the model performed well in all cases. After local calibration, the model gave estimates of mean annual NO2 concentrations within a factor of 1.5 of the actual mean (approx. 70-90%) of the time and within a factor of 2 between 70 and 100% of the time. r2 values between modelled and observed concentrations are in the range of 0.58-0.76. These results are comparable to those achieved by more sophisticated dispersion models. The model also has several advantages over dispersion modelling. It is able, for example, to provide high-resolution maps across a whole urban area without the need to interpolate between receptor points. It also offers substantially reduced costs and processing times compared to formal dispersion modelling. It is concluded that the model might thus be used as a means of mapping long-term air pollution concentrations either in support of local authority air-quality management strategies, or in epidemiological studies.

Analysing spatially referenced public health data: a comparison of three methodological approaches.

In the analysis of spatially referenced public health data, members of different disciplinary groups (geographers, epidemiologists and statisticians) tend to select different methodological approaches, usually those with which they are already familiar. This paper compares three such approaches in terms of their relative value and results. A single public health dataset, derived from a community survey, is analysed by using 'traditional' epidemiological methods, GIS and point pattern analysis. Since they adopt different 'models' for addressing the same research question, the three approaches produce some variation in the results for specific health-related variables. Taken overall, however, the results complement, rather than contradict or duplicate each other.

The influence of vegetation on the horizontal and vertical distribution of pollutants in a street canyon.

Space constraints in cities mean that there are only limited opportunities for increasing tree density within existing urban fabric and it is unclear whether the net effect of increased vegetation in street canyons is beneficial or detrimental to urban air quality at local scales. This paper presents data from a field study undertaken in Auckland, New Zealand designed to determine the local impact of a deciduous tree canopy on the distribution of the oxides of nitrogen within a street canyon. The results showed that the presence of leaves on the trees had a marked impact on the transport of pollutants and led to a net accumulation of pollutants in the canyon below the tree tops. The incidence and magnitude of temporally localised spikes in pollutant concentration were reduced within the tree canopy itself. A significant difference in pollutant concentrations with height was not observed when leaves were absent. Analysis of the trends in concentration associated with different wind directions showed a smaller difference between windward and leeward sides when leaves were on the trees. A small relative increase in concentrations on the leeward side was observed during leaf-on relative to leaf-off conditions as predicted by previous modelling studies. However the expected reduction in concentrations on the windward side was not observed. The results suggest that the presence of leaves on the trees reduces the upwards transport of fresh vehicle emissions, increases the storage of pollutants within the canopy space and reduces the penetration of clean air downwards from aloft. Differences observed between NO and NO(2) concentrations could not be accounted for by dispersion processes alone, suggesting that there may also be some changes in the chemistry of the atmosphere associated with the presence of leaves on the trees.