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Background: Smoking contributes to the 7 to 8 year gap between Maori and non-Maori life expectancy (2006 Census). To inform current discussions by policy-makers on tobacco control, we estimate life-expectancy in 2040 for Maori and... more
Background: Smoking contributes to the 7 to 8 year gap between Maori and non-Maori life expectancy (2006 Census). To inform current discussions by policy-makers on tobacco control, we estimate life-expectancy in 2040 for Maori and non-Maori, never-smokers and current-smokers. If nobody smoked tobacco from 2020 onwards, then life expectancy in 2040 will be approximated by projected never-smoker life expectancy. Method: Life-tables by sex/ethnicity/smoking status for 1996-99 were estimated by merging official Statistics New Zealand life-tables, census data and linked census-mortality rate estimates. We specified six modelling scenarios, formed by combining two options for future per annum declines in mortality rates among never-smokers (1.5%/2.5% and 2.0%/3.5% for non-Maori/Maori; i.e. assuming a return to long-run trends of closing ethnic gaps as in pre-1980s decades), and three options for future per annum reductions in the mortality rate difference comparing current to never-smokers (0%, 1% and 2%). Results: In 1996-1999, current smokers had an estimated 3.9 to 7.4 years less of life expectancy relative to never-smokers. This smoking difference in life expectancy was less among Maori than among non-Maori. If the 2006 census smoking prevalence remains unchanged into the future, we estimate the difference in 2040 between Maori and non-Maori life expectancy will range from 1.8 to 6.1 years across the six scenarios and two sexes (average 3.8). If nobody smokes tobacco from 2020 onwards, we estimate additional gains in life expectancy for Maori ranging from 2.5 to 7.9 years (average 4.7) and for non-Maori ranging from 1.2 to 5.4 years (average 2.9). Going smokefree as a nation by 2020, compared to no change from the 2006 Census population smoking prevalence, will close ethnic inequalities in life expectancy by 0.3 to 4.6 years (average 1.8 years; consistently greater for females). Discussion: If smoking persists at current rates it will become an even greater constraint on life expectancy improvements for New Zealanders in the future. Continued increases in life expectancy, and closing of the Maori:non-Maori gaps in life expectancy, would be greatly assisted by the end of tobacco smoking in Aotearoa-New Zealand by 2020.
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Houses in New Zealand have inadequate space heating and a third of households use unflued gas heaters. As part of a large community intervention trial to improve space heating, we replaced ineffective heaters with more effective,... more
Houses in New Zealand have inadequate space heating and a third of households use unflued gas heaters. As part of a large community intervention trial to improve space heating, we replaced ineffective heaters with more effective, non-polluting heaters. This paper assesses the contribution of heating and household factors to indoor NO2 in almost 350 homes and reports on the reduction in NO2 levels due to heater replacement. Homes using unflued gas heaters had more than three times the level of NO2 in living rooms [geometric mean ratio (GMR) = 3.35, 95% CI: 2.83-3.96, P < 0.001] than homes without unflued gas heaters, whereas homes using gas stove-tops had significantly elevated living room NO2 levels (GMR = 1.42, 95% CI: 1.05-1.93, P = 0.02). Homes with heat pumps, flued gas heating, or enclosed wood burners had significantly lower levels of NO2 in living areas and bedrooms. In homes that used unflued gas heaters as their main form of heating at baseline, the intervention was associated with a two-third (67%) reduction in NO2 levels in living rooms, when compared with homes that continued to use unflued gas heaters. Reducing the use of unflued gas heating would substantially lower NO2 exposure in New Zealand homes. Understanding the factors influencing indoor NO2 levels is critical for the assessment and control of indoor air pollution. This study found that homes that used unflued gas combustion appliances for heating and cooking had higher NO2 levels compared with homes where other fuels were used. These findings require institutional incentives to increase the use of more effective, less polluting fuels, particularly in the home environment.
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Associations between cellular telephone use and risk of brain tumors have been examined in a number of epidemiological studies including INTERPHONE. Although results revealed no positive associatio...
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This chapter positions the late Tony McMichael’s contributions in the social, political and ecological context in which he worked from the early 1970s to the present. We document how his research and writing were shaped by this milieu and... more
This chapter positions the late Tony McMichael’s contributions in the social, political and ecological context in which he worked from the early 1970s to the present. We document how his research and writing were shaped by this milieu and explore some of the barriers, challenges and opportunities that shaped his career. McMichael’s work was distinguished in two respects. These are, first, the range of epidemiology subspecialties that he mastered (including occupational health, cancer, nutrition and environmental health), and second, the depth and lasting impact of his research. We provide examples of the work he and his colleagues carried out on lead, smoking, health inequalities and the links between diet and cancer. In recent decades, Tony was probably known best for his focus on the effects of adverse global ecological and environmental changes, and climate change in particular. He contributed to an improved understanding of causality within epidemiology, rejecting an exclusive f...
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Background Exposure to high doses of ionizing radiation is among the few well-established brain tumour risk factors. We used data from the Interphone study to evaluate the effects of exposure to low-dose radiation from diagnostic... more
Background Exposure to high doses of ionizing radiation is among the few well-established brain tumour risk factors. We used data from the Interphone study to evaluate the effects of exposure to low-dose radiation from diagnostic radiological examinations on glioma, meningioma and acoustic neuroma risk. Methods Brain tumour cases (2644 gliomas, 2236 meningiomas, 1083 neuromas) diagnosed in 2000–02 were identified through hospitals in 13 countries, and 6068 controls (population-based controls in most centres) were included in the analysis. Participation across all centres was 64% for glioma cases, 78% for meningioma cases, 82% for acoustic neuroma cases and 53% for controls. Information on previous diagnostic radiological examinations was obtained by interviews, including the frequency, timing and indication for the examinations. Typical brain doses per type of examination were estimated based on the literature. Examinations within the 5 years before the index date were excluded from...
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Research Interests: Business, Climate Change, Toxicology, Air pollution, Medicine, and 12 moreDisease Outbreaks, Environmental Sciences, Humans, Climate Change Mitigation, Stakeholder Engagement, Comparability, Epidemiologic Studies, Coronavirus, CoVid, SARS-CoV-2, Severe Acute Respiratory Syndrome, and Medical and Health Sciences
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To date, greenhouse gas (GHG) emissions, mitigation strategies and the accompanying health co-benefits in different economic sectors have not been fully investigated. The purpose of this paper is to review comprehensively the evidence on... more
To date, greenhouse gas (GHG) emissions, mitigation strategies and the accompanying health co-benefits in different economic sectors have not been fully investigated. The purpose of this paper is to review comprehensively the evidence on GHG mitigation measures and the related health co-benefits, identify knowledge gaps, and provide recommendations to promote further development and implementation of climate change response policies. Evidence on GHG emissions, abatement measures and related health co-benefits has been observed at regional, national and global levels, involving both low- and high-income societies. GHG mitigation actions have mainly been taken in five sectors: energy generation, transport, food and agriculture, household and industry, consistent with the main sources of GHG emissions. GHGs and air pollutants to a large extent stem from the same sources and are inseparable in terms of their atmospheric evolution and effects on ecosystem; thus, GHG reductions are usuall...
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Reducing the exposure of children and young people to the marketing of unhealthy foods is a core strategy for reducing the high overweight and obesity prevalence in this population. The Advertising Standards Authority (ASA) has recently... more
Reducing the exposure of children and young people to the marketing of unhealthy foods is a core strategy for reducing the high overweight and obesity prevalence in this population. The Advertising Standards Authority (ASA) has recently reviewed its self-regulatory codes and proposed a revised single code on advertising to children. This article evaluates the proposed code against eight criteria for an effective code, which were included in a submission to the ASA review process from over 70 New Zealand health professors. The evaluation found that the proposed code largely represents no change or uncertain change from the existing codes, and cannot be expected to provide substantial protection for children and young people from the marketing of unhealthy foods. Government regulations will be needed to achieve this important outcome.
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When investigating the association between brain tumors and use of mobile telephones, accurate data on tumor position are essential, due to the highly localized absorption of energy in the human brain from the radio-frequency fields... more
When investigating the association between brain tumors and use of mobile telephones, accurate data on tumor position are essential, due to the highly localized absorption of energy in the human brain from the radio-frequency fields emitted. We used a point process model to investigate this association using information that included tumor localization data from the INTERPHONE Study (Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden, and the United Kingdom). Our main analysis included 792 regular mobile phone users diagnosed with a glioma between 2000 and 2004. Similar to earlier results, we found a statistically significant association between the intracranial distribution of gliomas and the self-reported location of the phone. When we accounted for the preferred side of the head not being exclusively used for all mobile phone calls, the results were similar. The association was independent of the cumulative call time and cumula...
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With rapid economic development, China has been plagued by choking air pollution in recent years, and the frequent occurrence of haze episodes has caused widespread public concern. The purpose of this study is to describe the sources and... more
With rapid economic development, China has been plagued by choking air pollution in recent years, and the frequent occurrence of haze episodes has caused widespread public concern. The purpose of this study is to describe the sources and formation of haze, summarize the mitigation measures in force, review the relationship between haze pollution and public health, and to discuss the challenges, potential research directions and policy options. Haze pollution has both natural and man-made causes, though it is anthropogenic sources that are the major contributors. Accumulation of air pollutants, secondary formation of aerosols, stagnant meteorological conditions, and trans-boundary transportation of pollutants are the principal causes driving the formation and evolution of haze. In China, haze includes gaseous pollutants and fine particles, of which PM2.5 is the dominant component. Short and long-term exposure to haze pollution are associated with a range of negative health outcomes, ...
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Recent evidence suggests that there may be an interaction between air pollution and heat on mortality, which is pertinent in the context of global climate change. We sought to examine this interaction in Hefei, a hot and polluted Chinese... more
Recent evidence suggests that there may be an interaction between air pollution and heat on mortality, which is pertinent in the context of global climate change. We sought to examine this interaction in Hefei, a hot and polluted Chinese city. We conducted time-series analyses using daily mortality, air pollutant concentration (including particulate matter with aerodynamic diameter <10μm (PM10), sulphur dioxide (SO2) and nitrogen dioxide (NO2)), and temperature data from 2008 to 2014. We applied quasi-Poisson regression models with natural cubic splines and examined the interactive effects using temperature-stratified models. Subgroup analyses were conducted by age, gender, and educational levels. We observed consistently stronger associations between air pollutants and mortality at high temperatures than at medium temperatures. These differences were statistically significant for the associations between PM10 and non-accidental mortality and between all pollutants studied and re...
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Temperature extremes and air pollution both pose significant threats to human health, but it remains uncertain whether pollutants' effects on mortality are modified by temperature levels. In this review, we summarized epidemiologic... more
Temperature extremes and air pollution both pose significant threats to human health, but it remains uncertain whether pollutants' effects on mortality are modified by temperature levels. In this review, we summarized epidemiologic evidence on the modification by temperature of the acute effects of air pollutants on non-accidental and cardiovascular mortality. The EMBASE, PubMed, ProQuest Dissertations and Theses, and Elsevier Science Direct databases were used to identify papers published up to 2nd December 2014. Studies with appropriate design, exposures and outcome indicators, quantitative estimates and high/intermediate quality were included. Twenty-one studies met the inclusion criteria, of which 12 reported the effects of PM10 on mortality modified by temperature, 10 studied O3, and the rest examined NO2, SO2, PM2.5, PM10-2.5, CO and black smoke. We divided temperature into low, medium, and high categories as defined in each study. In high temperature days, a 10μg/m(3) inc...
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To determine whether individuals from two rural communities with heavy exposure to the Rabbit Haemorrhagic Disease Virus (RHDV) developed antibodies to this virus. Sera were assayed using competition ELISA (cELISA) and solid phase ELISA... more
To determine whether individuals from two rural communities with heavy exposure to the Rabbit Haemorrhagic Disease Virus (RHDV) developed antibodies to this virus. Sera were assayed using competition ELISA (cELISA) and solid phase ELISA (spELISA). Exposure estimates were based on answers to an interviewer administered questionnaire. Of the 104 participants, 79 were considered to have experienced high or medium exposure, many of whom described specific exposures. There were 58 people who reported contact with RHDV infected bait, organ homogenate mixtures or rabbit body fluids. A one-way analysis of variance (Kruskal Wallis) found that human cELISA results were differently distributed from both strongly RHDV positive rabbits (chi2(1) = 27.37, p < 0.001) and weakly RHDV positive rabbits (chi2(1) = 27.35, p < 0.001). The distribution of assay results in each exposure group did not differ in either cELISA (chi2(2) = 2.49, p = 0.29) or spELISA (chi2(2) = 1.70, p = 0.43). Relatively ...
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To estimate (a) the prevalence of gene variants associated with slow nicotine metabolism in the general Maori population and (b) nicotine intake and metabolic rate in Maori and European smokers. The procedure involved (a) genotyping 85... more
To estimate (a) the prevalence of gene variants associated with slow nicotine metabolism in the general Maori population and (b) nicotine intake and metabolic rate in Maori and European smokers. The procedure involved (a) genotyping 85 Maori participants for cytochrome P-450 2A6 (CYP2A6) gene variants, which are associated with reduced nicotine metabolic rate (ie CYP2A6*9 and *4); and (b) measuring salivary cotinine (COT) and trans-3'-hydroxycotinine (3-HC) as biomarkers of nicotine intake and metabolic rate in 12 female smokers from the Hawke's Bay Region (6 Maori and 6 European). (a) The frequencies of the slow nicotine metabolising variants, CYP2A6*9 and *4, were significantly higher in Maori compared to European…
Research Interests: Genetics, Public Health, Medicine, Humans, Nicotine, and 15 moreFemale, Pubmed, New Zealand, Prevalence, Metabolic rate, Genotype, European Continental Ancestry Group, Biological markers, Nicotine Replacement Therapy, Ethnic Difference, General Population, Cotinine, Gene frequency, Medical and Health Sciences, and Cigarette Smoke
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The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control... more
The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure for epidemiological studies, we assessed determinants of mobile phone output power in a multinational study. More than 500 volunteers in 12 countries used Global System for Mobile communications software-modified phones (GSM SMPs) for approximately 1 month each. The SMPs recorded date, time, and duration of each call, and the frequency band and output power at fixed sampling intervals throughout each call. Questionnaires provided information on the typical circumstances of an individual&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s phone use. Linear regression models were used to analyse the influence of possible explanatory variables on the average output power and the percentage call time at maximum power for each call. Measurements of over 60,000 phone calls showed that the average output power was approximately 50% of the maximum, and that output power varied by a factor of up to 2 to 3 between study centres and network operators. Maximum power was used during a considerable proportion of call time (39% on average). Output power decreased with increasing call duration, but showed little variation in relation to reported frequency of use while in a moving vehicle or inside buildings. Higher output powers for rural compared with urban use of the SMP were observed principally in Sweden where the study covered very sparsely populated areas. Average power levels are substantially higher than the minimum levels theoretically achievable in GSM networks. Exposure indices could be improved by accounting for average power levels of different telecommunications systems. There appears to be little value in gathering information on circumstances of phone use other than use in very sparsely populated regions.
Research Interests: Computer Science, Cell Phones, Medicine, Exposure Assessment, Humans, and 15 moreFemale, Male, GSM, Electromagnetic Field, Mobile phone, Clinical Sciences, Middle Aged, Occupational, Adult, Phone, Linear Regression Model, Epidemiologic Studies, Environmental Exposure, Case Control Studies, and Occupational and environmental medicine
ABSTRACT Background: Evidence from NZ and overseas suggests that gastrointestinal diseases transmitted by drinking-water contribute significantly to the disease burden in developed countries. However there has been no systematic or... more
ABSTRACT Background: Evidence from NZ and overseas suggests that gastrointestinal diseases transmitted by drinking-water contribute significantly to the disease burden in developed countries. However there has been no systematic or strategic research in New Zealand to examine the size of the burden of endemic gastrointestinal disease, risk factors for illness, or sources of infection. Our aim was to test the relationship between acute gastrointestinal disease and quality of drinking-water, as measured by (i) actual levels of contamination with indicator organisms and Campylobacter, (ii) transgression of microbial drinking-water standards, (iii) grading of water supply by the Ministry of Health, and (iv) traditional Maori value of the water supply. Methods: The sampling frame comprised all primary schools of more than 90 children that were on municipal water supplies. All schools on poor water quality supplies (ie &gt;5% of routine samples contaminated with E. coli) were asked to participate and were matched by geographic location and socioeconomic status with an equal number of schools that had good water quality supplies (ie. those of Aa-Bb grade and that complied with the current New Zealand Drinking-Water Standards). A daily diary was used to gather information about water usage, selfreported gastrointestinal disease (GID) and several potential confounding factors from a cohort of 1,194 primary school-aged children over a sevenweek period, at which time the drinking-water quality at each school was monitored. Results: Preliminary results indicate that poor quality drinking-water supplies are a significant cause of GID, relative risk of 1.35 (95% CI of 1.09-1.65; P &lt; 0.05) and an attributable risk of 0.075. These results must be viewed with caution as only 15% of the pupils at the selected schools chose to participate in the diary study, giving rise to potentially serious selection bias although once enlisted the response rate was 85%. Selection bias was addressed by a preliminary questionnaire that sought information about exposure of 1,194 participants and 1,685 non-participants to confounding factors, which showed that similar exposures were reported by both groups for most attributes measured. However, participants reported significantly higher exposure than non-participants to animals. Conclusion. The elevated risk of GID attributed to poor quality drinking-water applies to the 11% of the population not connected to a community water supply and the 10% that are connected to d or e grade or ungraded community drinking-water supplies, with a population attributable risk of 1.4%.
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To determine whether measurement of cotinine in saliva is a sensitive measure of exposure to second-hand smoke (SHS) among customers in bars. Before/after comparison of saliva cotinine and subjective assessments of SHS. Three bars in... more
To determine whether measurement of cotinine in saliva is a sensitive measure of exposure to second-hand smoke (SHS) among customers in bars. Before/after comparison of saliva cotinine and subjective assessments of SHS. Three bars in Wellington, New Zealand, June 2003. Eleven non-smoking medical students spent three hours in each location. They provided saliva samples before and after the visit, counted numbers of lit cigarettes in each bar, and assessed the smokiness of the venue. Samples were tested for cotinine using liquid chromatography coupled with mass spectrometry. Cotinine levels post-visit were consistently higher than baseline. The mean difference was 1.03 ng/mL with a 95% confidence interval of 0.76-1.30 ng/ mL. Adjustments to post-visit levels for metabolism and clearance of cotinine made very little difference to these results. Males tended to have higher baseline levels than females, and to show smaller increases. The bar with the greatest increase in cotinine was judged to be the smokiest on the basis of averaged cigarette counts and scores for presence of smoke and odour. The cotinine in saliva, when tested with the analytic methods described here, provides a means of assessing relatively short-term exposures to SHS.
Research Interests: Mass Spectrometry, Medicine, Applied Economics, Humans, Nicotine, and 12 moreFemale, Male, High Performance Liquid Chromatography, Saliva, Public Administration and Policy, Adult, Public health systems and services research, Second-hand smoke, Cotinine, Confidence Interval, tobacco smoke pollution, and Cigarette Smoke
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Research Interests: Demography, Education, Gerontology, Public Transport, Physical Activity, and 14 moreMedicine, Transport policy, Older people, New Zealand, Psychological Intervention, Census, Cycling, Data Collection, Behavioral, Personal Income, Active Transport, Individual Difference, Economic Benefit, and Medical and Health Sciences
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The transport system influences everyone’s wellbeing on a daily basis. These impacts are both positive and negative and are borne directly and indirectly at a range of spatial and... more
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The transport system influences everyone’s wellbeing on a daily basis. These impacts are both positive and negative and are borne directly and indirectly at a range of spatial and temporal scales and across different groups in society. Furthermore, they are often distributed unfairly and the people who are least able to use transport networks frequently bear the greatest costs. People also have various transport needs and these needs change throughout their lives. Due to these complexities, there is no straightforward answer as to how we should provide transport fairly. Policies and actions to decarbonise the transport system are urgently needed, but their equity effects are also important. We give a brief overview of distributive justice and equity in transport literature. We then develop a conceptual framework of distributive justice and a set of four principles to guide the application of the framework to transport policy....
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Evidence is mounting to suggest a causal relationship between the built environment and people's physical activity behaviours, particularly active transport. The evidence base has been hindered to date by restricted consideration of... more
Evidence is mounting to suggest a causal relationship between the built environment and people's physical activity behaviours, particularly active transport. The evidence base has been hindered to date by restricted consideration of cost and economic factors associated with built environment interventions, investigation of socioeconomic or ethnic differences in intervention effects, and an inability to isolate the effect of the built environment from other intervention types. The aims of this systematic review were to identify which environmental interventions increase physical activity in residents at the local level, and to build on the evidence base by considering intervention cost, and the differential effects of interventions by ethnicity and socioeconomic status. A systematic database search was conducted in June 2015. Articles were eligible if they reported a quantitative empirical study (natural experiment or a prospective, retrospective, experimental, or longitudinal re...
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Few studies have been conducted to investigate the acute health effects of visibility and haze, which may be regarded as proxy indicators of ambient air pollution. We used a distributed lag non-linear model (DLNM) combined with... more
Few studies have been conducted to investigate the acute health effects of visibility and haze, which may be regarded as proxy indicators of ambient air pollution. We used a distributed lag non-linear model (DLNM) combined with quasi-Poisson regression to estimate the relationship between visibility, haze and mortality in Ningbo, a coastal city of China. We found that the mortality risk of visibility was statistically significant only on the current day, while the risk of haze and PM10 peaked on the second day and could last for three days. When the visibility was less than 10 km, each 1 km decrease of visibility at lag 0 day was associated with a 0.78% (95% CI: 0.22-1.36%) increase in total mortality and a 1.61% (95% CI: 0.39-2.85%) increase in respiratory mortality. The excess risk of haze at lag 0-2 days on total mortality, cardiovascular and respiratory mortality was 7.76% (95% CI: 3.29-12.42%), 7.73% (95% CI: 0.12-15.92%) and 17.77% (95% CI: 7.64-28.86%), respectively. Greater ...
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Limited information is available on the perceptions of stakeholders concerning the health co-benefits of greenhouse gas (GHG) emission reductions. The purpose of this study was to investigate the perceptions of urban residents on the... more
Limited information is available on the perceptions of stakeholders concerning the health co-benefits of greenhouse gas (GHG) emission reductions. The purpose of this study was to investigate the perceptions of urban residents on the health co-benefits involving GHG abatement and related influencing factors in three cities in China. Beijing, Ningbo and Guangzhou were selected for this survey. Participants were recruited from randomly chosen committees, following quotas for gender and age in proportion to the respective population shares. Chi-square or Fisher's exact tests were employed to examine the associations between socio-demographic variables and individuals' perceptions of the health co-benefits related to GHG mitigation. Unconditional logistic regression analysis was performed to investigate the influencing factors of respondents' awareness about the health co-benefits. A total of 1159 participants were included in the final analysis, of which 15.9% reported that...
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Few studies examined the associations of meteorological factors with road traffic injuries (RTIs). The purpose of the present study was to quantify the contributions of meteorological factors to RTI cases treated at a tertiary level... more
Few studies examined the associations of meteorological factors with road traffic injuries (RTIs). The purpose of the present study was to quantify the contributions of meteorological factors to RTI cases treated at a tertiary level hospital in Shantou city, China. A time-series diagram was employed to illustrate the time trends and seasonal variation of RTIs, and correlation analysis and multiple linear regression analysis were conducted to investigate the relationships between meteorological parameters and RTIs. RTIs followed a seasonal pattern as more cases occurred during summer and winter months. RTIs are positively correlated with temperature and sunshine duration, while negatively associated with wind speed. Temperature, sunshine hour and wind speed were included in the final linear model with regression coefficients of 0.65 (t = 2.36, P = 0.019), 2.23 (t = 2.72, P = 0.007) and -27.66 (t = -5.67, P < 0.001), respectively, accounting for 19.93% of the total variation of RTI...
The incidence of early childhood acute respiratory infections (ARIs) has been associated with aspects of the indoor environment. In recent years, public awareness about some of these environmental issues has increased, including new laws... more
The incidence of early childhood acute respiratory infections (ARIs) has been associated with aspects of the indoor environment. In recent years, public awareness about some of these environmental issues has increased, including new laws and subsequent changes in occupant behaviours. This New Zealand study investigated current exposures to specific risk factors in the home during the first five years of life and provided updated evidence on the links between the home environment and childhood ARI hospitalisation. Pregnant women (n = 6822) were recruited in 2009 and 2010, and their 6853 children created a child cohort that was representative of New Zealand births from 2007-10. Longitudinal data were collected through face-to-face interviews and linkage to routinely collected national datasets. Incidence rates with Poisson distribution confidence intervals were computed and Cox regression modelling for repeated events was performed. Living in a rented dwelling (48%), household crowdin...
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Associations between cellular telephone use and glioma risk have been examined in several epidemiological studies including the 13-country INTERPHONE study. Although results showed no positive association between cellular telephone use... more
Associations between cellular telephone use and glioma risk have been examined in several epidemiological studies including the 13-country INTERPHONE study. Although results showed no positive association between cellular telephone use and glioma risk overall, no increased risk for long-term users, and no exposure-response relationship, there was an elevated risk for those in the highest decile of cumulative call time. However, results may be biased as data were collected during a period of rapidly increasing cellular telephone use, and as controls were usually interviewed later in time than cases. Further analyses were conducted in a subset of five INTERPHONE study countries (Australia, Canada, France, Israel, New Zealand) using a post hoc matching strategy to optimize proximity of case-to-control interview dates and age. Although results were generally similar to the original INTERPHONE study, there was some attenuation of the reduced odds ratios and stronger positive associations among long-term users and those in the highest categories for cumulative call time and number of calls (eighth-ninth and 10th decile). Proximity and symmetry in timing of case-to-control interviews should be optimized when exposure patterns are changing rapidly with time.
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To measure secondhand smoke (SHS) levels in New Zealand bars prior to smokefree legislation enacted on 10 December 2004. Thirty bars were randomly selected from urban, surburban, and surrounding rural areas of Auckland, Wellington, and... more
To measure secondhand smoke (SHS) levels in New Zealand bars prior to smokefree legislation enacted on 10 December 2004. Thirty bars were randomly selected from urban, surburban, and surrounding rural areas of Auckland, Wellington, and Invercargill. Bars were visited (on a Friday or Saturday night for a 3-hour stay between 1800 and 2400 hours) in July/August/September 2004 (winter) and again in October/November 2004 (spring). Each bar was visited by a group of 4 or 5 non-smokers participating in the study. All groups of participants spent a 3-hour block of continuous time in the bar. Saliva samples (approximately 0.5-2 mL) were provided immediately prior to entering the bar as well as 5-15 minutes after leaving the bar. Each group recorded the initial impression of air quality and ventilation, the number of observed lit cigarettes over three 10-minute intervals throughout the evening, and the number of patrons at each interval. In addition, any general comments about the venue (relevant to bar attendance or air quality on the evening) was recorded. Cotinine, the main metabolite of nicotine, was measured in saliva samples using Liquid Chromatography with tandem Mass Spectrometry (LC-MS-MS). In all bars, and in all volunteers, exposure to SHS was evident. Saliva cotinine increased after 3 hours in the bar (mean increase=0.66 ng/mL, SE=0.03 ng/mL, p value of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.0001). The 30 bars randomly selected provided a good spectrum of SHS exposures, with mean cotinine increasing by approximately 8-fold. Smaller population centres showed greater exposures to SHS. A north-south gradient of exposure was also seen (highest exposures were in Southland). Higher exposures were seen in the winter than in the spring. The objective measures of SHS exposure correlated strongly with the volunteers&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; subjective observation of ventilation, air quality, and counts of lit cigarettes. One exception was where objective salivary markers indicated that even &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;seemingly smokefree&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; venues with &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;good ventilation&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; produced discernable levels of SHS exposure. We have utilised an objective, non-invasive scientific approach to assess SHS smoke exposure in patrons of New Zealand bars. Our results clearly indicate exposure to SHS, with regional and seasonal variation, prior to the introduction of smokefree legislation.
Research Interests: Air Quality, Secondhand Smoke Exposure, Environmental Monitoring, Humans, Legislation, and 15 moreNew Zealand, Restaurants, Tandem Mass Spectrometry, Seasonal variation, Spectrum, Smoking Ban, Saliva, Liquid Chromatography, Health surveys, Rural Area, Seasons, Continuous Time Systems, Cotinine, Continuous time, and Medical and Health Sciences
Tibet is especially vulnerable to climate change due to the relatively rapid rise of temperature over past decades. The effects on mortality and morbidity of extreme heat in Tibet have been examined in previous studies; no heat adaptation... more
Tibet is especially vulnerable to climate change due to the relatively rapid rise of temperature over past decades. The effects on mortality and morbidity of extreme heat in Tibet have been examined in previous studies; no heat adaptation initiatives have yet been implemented. We estimated heat vulnerability of urban and rural populations in 73 Tibetan counties and identified potential areas for public health intervention and further research. According to data availability and vulnerability factors identified previously in Tibet and elsewhere, we selected 10 variables related to advanced age, low income, illiteracy, physical and mental disability, small living spaces and living alone. We separately created and mapped county-level cumulative heat vulnerability indices for urban and rural residents by summing up factor scores produced by a principal components analysis (PCA). For both study populations, PCA yielded four factors with similar structure. The components for rural and urb...
Research Interests:
There is increased interest in the effectiveness and cobenefits of measures to promote walking and cycling, including health gains from increased physical activity and reductions in fossil fuel use and vehicle emissions. This paper... more
There is increased interest in the effectiveness and cobenefits of measures to promote walking and cycling, including health gains from increased physical activity and reductions in fossil fuel use and vehicle emissions. This paper analyses the changes in walking and cycling in two New Zealand cities that accompanied public investment in infrastructure married with programmes to encourage active travel. Using a quasi-experimental two-group pre-post study design, we estimated changes in travel behaviour from baseline in 2011 to mid-programme in 2012, and postprogramme in 2013. The intervention and control cities were matched in terms of sociodemographic variables and baseline levels of walking and cycling. A face-to-face survey obtained information on walking and cycling. We also drew from the New Zealand Travel Survey, a national ongoing survey of travel behaviour, which was conducted in the study areas. Estimates from the two surveys were combined using meta-analysis techniques. Th...
Research Interests: Human Geography, Health Promotion, Transportation, Adolescent, Automobiles, and 15 moreCities, Humans, Child, Bicycling, Female, Male, New Zealand, Infant, Middle Aged, Adult, Public health systems and services research, Environment Design, Motor activity, Surveys and Questionnaires, and Child preschool
Background Tibet, average altitude more than 4,000 meters, is warming faster than anywhere else in China. The increase in temperatures may aggravate existing health problems and lead to the emergence of new risks. However, there are no... more
Background Tibet, average altitude more than 4,000 meters, is warming faster than anywhere else in China. The increase in temperatures may aggravate existing health problems and lead to the emergence of new risks. However, there are no actions being taken at present to protect population health due to limited understanding about the range and magnitude of health effects of climate change. Methods The study was a cross-sectional survey of 619 respondents from urban Lhasa, Tibet in August 2012 with the aim to investigate public perceptions of risk, heat experiences, and coping resources. Results Respondents are aware of the warming that has occurred in Lhasa in recent years. Over 78% reported that rising temperature is either a “very” or “somewhat” serious threat to their own health, and nearly 40% reported they had experienced heat-related symptoms. Sex, age, education and income influenced perceived risks, health status, and heat experience. The vast majority of respondents reported...
Research Interests: Geography, Perception, Climate Change, Behavior, Environmental Health, and 13 moreRisk, Tibet, Adolescent, Medicine, Cities, Humans, Female, Male, Young Adult, Health Status, Aged, Middle Aged, and Adult(Risk, Tibet, Adolescent, Medicine, Cities, Humans, Female, Male, Young Adult, Health Status, Aged, Middle Aged, and Adult)
(Risk, Tibet, Adolescent, Medicine, Cities, Humans, Female, Male, Young Adult, Health Status, Aged, Middle Aged, and Adult)