Health Impact Model Research Articles

A29 Physical Activity through Sustainable Transport Approaches (PASTA) – a pan-European web-based survey on determinants of active travel behaviour using an opportunistic sampling approach

Abstract Background Active travel (AT), i.e. walking and bicycling, is a promising approach to increase physical activity (PA). Research on determinants of AT is growing and health impact models (HIM) demonstrate benefits of AT. However, substantial research gaps remain. The PASTA project (www.pastaproject.eu) is a broad study of determinants of AT including safety, measures to promote AT, and HIM. It integrates planning, travel behavior and health research, policy and practice. Methods PASTA is a 4-year project (2013-2017) involving 7 European cities (Antwerp, Barcelona, Oerebro, Rome, Vienna, Zurich). A longitudinal web-based survey which consists of a substantial baseline questionnaire (on average 120 data points) and bi-weekly short (14) and a monthly long (21) follow-ups was launched in November 2014. Survey contents were defined based on a comprehensive conceptual framework which combines a rationalist mode choice, a socio-geographical and a socio-psychological perspective. In addition it includes PA (adapted GPAQ separating walking and cycling) and health related items. Participants experiencing crashes fill out an additional questionnaire. Participants are recruited opportunistically on a rolling basis (target sample size: 2000 per city) and sample characteristics are monitored on an ongoing basis. Parts of the sample will be recruited randomly. Subsamples are used to evaluate AT measures (pre-post) and to collect objective data as part of add-on modules (GPS tracking, accelerometry, air pollution exposure). Results To date, 1802 participants have been recruited, mainly in Antwerp (1168) and Barcelona (300). Preliminary data suggests drop-out rates of 20-25% for short and approximately 50% for long follow-up questionnaires. Questionnaire completion rate (80% of average data input) are above 80% for baseline, above 90% for short and 85% for long follow-up questionnaire. Users report on average 1.4 trips per day in travel diary. 54% of participants are women. 65% report walking and 12% report biking daily or almost daily. Conclusions The PASTA survey promises to provide insights on variation in travel and physical activity behavior over time, which is important for HIM and various other issues in AT research. Survey implementation has passed a first test of practicality and monitoring features to optimize sample distribution and recruitment strategies are in place. Early results are promising with regards to representative sample distribution and how extraordinary user burden of frequent follow-ups is handled. By July we will be able to report more reliable participation statistics including additional cities and participant attributes, as well as comparisons with the target populations.

⁎A40 Integrating Transportation and Health with Policy, Funding, Data Collection and Model Calibration in Nashville, Tennessee (United States)

Abstract Background Tennessee was the least physically active US state in 2011, and among the top 5 most obese states in 2013. To address these issues, the Nashville area Metropolitan Planning Organization (MPO) is integrating health into the transportation planning process and increasing opportunities for active transportation. Our purpose is to describe the policy and research initiatives related to these areas. Methods Regarding policy, the MPO first adopted three policy priorities that Nashville residents identified in a transportation opinion survey: public transit, active transportation, and infrastructure preservation. Next, the MPO devised a transportation project scoring and selection system in which 60% of the criteria quantified how a future roadway project could increase opportunities for active transportation. Additionally, the MPO reserved 15% of its primary allocation from the U.S. Department of Transportation to fund its Active Transportation Program (ATP) for bicycle- and pedestrian-specific infrastructure and programs. Regarding research, the MPO conducted the Middle Tennessee Transportation and Health Study (MTTHS, n=6,000 households, 11,000+ individuals) to measure transportation behaviors and health attributes. Health questions included height, weight, general diet and health quality, and estimated time spent in physical activity and sitting. These data were used to calibrate the Integrated Transport and Health Impact Modeling (ITHIM) tool, which estimates the population health impacts of increased physical activity, reduced air pollution, and altered collision patterns. Results The policy changes in the MPO’s 2035 Regional Transportation Plan resulted in almost 70% of roadway projects including active transportation elements such as sidewalks and bikeways. In the previous 2030 plan, approximately 2% of roadway projects included these elements. Beyond roadway projects, the newly-funded ATP has awarded $13.6 million for active transportation infrastructure and education projects. The research conducted during the MTTHS yielded significant data about the transportation and health attributes of households throughout the MPO region. The data were used to create a Geographic Information System map of high health impact areas of the region, which are defined as areas with high prevalence of reported chronic diseases, low overall health quality, and low physical activity. The map enables the MPO staff to prioritize transportation projects in areas with potential positive health benefits. Finally, initial ITHIM modeling suggests that changes in physical activity, air-quality, and collisions may contribute to reduced mortality and morbidity in the region. Conclusions The Nashville Area MPO has made significant progress in integrating health into the transportation planning process by changing policy and allocating funding for active transportation research and modeling.

A novel approach to assess the population health impact of introducing a Modified Risk Tobacco Product

Based on the Food and Drug Administration’s Modified Risk Tobacco Product (MRTP) Application draft guideline, Philip Morris International (PMI) has developed a Population Health Impact Model to estimate the reduction in the number of deaths over a period following the introduction of an MRTP. Such a model is necessary to assess the effect that its introduction would have on population health, given the lack of epidemiological data available prior to marketing authorization on any risks from MRTPs. The model is based on publicly available data on smoking prevalence and on the relationships between smoking-related disease-specific mortality and various aspects of the smoking of conventional cigarettes (CCs), together with an estimate of exposure from the MRTP relative to that from CCs, and allows the exploration of possible scenarios regarding the effect of MRTP introduction on the prevalence of CC and MRTP use, individually and in combination. By comparing mortality attributable in a scenario where the MRTP is introduced with one where it is not, the model can estimate the mortality attributable to CCs and the MRTP, as well as the reduction in the deaths attributable to the introduction of the MRTP.

Bridging the Gap between Research and Clinical Practice in Asymptomatic Alzheimer's Disease.

Due to the growing global health impact of Alzheimer's disease (AD), there is a greater need for interventions that prevent or delay the onset of clinical symptoms of this debilitating disease. Clinical trials for disease-modifying compounds in AD have shifted towards earlier stages in the spectrum of illness, including the stage prior to cognitive symptoms. A population of specific interest for clinical research includes individuals with evidence of Alzheimer's disease pathology who are asymptomatic (ADPa). The challenges and barriers regarding medical treatment of ADPa must be identified and addressed prior to the completion of a positive clinical trial in order to accelerate the translation of research findings to clinical practice. This report applies an existing public health impact model from Spencer and colleagues (2013) to evaluate the readiness of the clinical practice environment to treat ADPa individuals if a disease-modifying agent achieves approval. We contrast the current clinical practice environment with a potential future state through investigating the effectiveness, reach, feasibility, sustainability, and transferability of the practice of treating ADPa individuals.

Trends of non-accidental, cardiovascular, stroke and lung cancer mortality in Arkansas are associated with ambient PM2.5 reductions.

The cardiovascular and stroke mortality rates in Arkansas are among the highest in the USA. The annual trends of stroke and cardiovascular mortality are barely correlated to smoking cessation; while the prevalence of risk factors such as obesity; cholesterol and hypertension increased over the 1979–2007 period. The study determined the effect of chronic exposure to PM2.5 on non-accidental; cardiovascular; stroke and lung cancer mortality in Arkansas over the 2000–2010 period using the World Health Organization’s log-linear health impact model. County chronic exposures to PM2.5 were computed by averaging spatially-resolved gridded concentrations using PM2.5 observations. A spatial uniformity was observed for PM2.5 mass levels indicating that chronic exposures were comparable throughout the state. The reduction of PM2.5 mass levels by 3.0 μg/m3 between 2000 and 2010 explained a significant fraction of the declining mortality. The effect was more pronounced in southern and eastern rural Arkansas as compared to the rest of the state. This study provides evidence that the implementation of air pollution regulations has measurable effects on mortality even in regions with high prevalence of major risk factors such as obesity and smoking. These outcomes are noteworthy as efforts to modify the major risk factors require longer realization times.

Health effects of the London bicycle sharing system: health impact modelling study

Objective To model the impacts of the bicycle sharing system in London on the health of its users.Design Health impact modelling and evaluation, using a stochastic simulation model.Setting Central and...

Four issues in undernutrition-related health impact modeling.

Undernutrition modeling makes it possible to evaluate the potential impact of such events as a food-price shock or harvest failure on the prevalence and severity of undernutrition. There are, however, uncertainties in such modeling. In this paper we discuss four methodological issues pertinent to impact estimation: (1) the conventional emphasis on energy intake rather than dietary quality; (2) the importance of the distribution of nutrient intakes; (3) the timing of both the ‘food shock’ and when the response is assessed; and (4) catch-up growth and risk accumulation.

Health Impact Modelling of Active Travel Visions for England and Wales Using an Integrated Transport and Health Impact Modelling Tool (ITHIM)

BackgroundAchieving health benefits while reducing greenhouse gas emissions from transport offers a potential policy win-win; the magnitude of potential benefits, however, is likely to vary. This study uses an Integrated Transport and Health Impact Modelling tool (ITHIM) to evaluate the health and environmental impacts of high walking and cycling transport scenarios for English and Welsh urban areas outside London.MethodsThree scenarios with increased walking and cycling and lower car use were generated based upon the Visions 2030 Walking and Cycling project. Changes to carbon dioxide emissions were estimated by environmental modelling. Health impact assessment modelling was used to estimate changes in Disability Adjusted Life Years (DALYs) resulting from changes in exposure to air pollution, road traffic injury risk, and physical activity. We compare the findings of the model with results generated using the World Health Organization's Health Economic Assessment of Transport (HEAT) tools.ResultsThis study found considerable reductions in disease burden under all three scenarios, with the largest health benefits attributed to reductions in ischemic heart disease. The pathways that produced the largest benefits were, in order, physical activity, road traffic injuries, and air pollution. The choice of dose response relationship for physical activity had a large impact on the size of the benefits. Modelling the impact on all-cause mortality rather than through individual diseases suggested larger benefits. Using the best available evidence we found fewer road traffic injuries for all scenarios compared with baseline but alternative assumptions suggested potential increases.ConclusionsMethods to estimate the health impacts from transport related physical activity and injury risk are in their infancy; this study has demonstrated an integration of transport and health impact modelling approaches. The findings add to the case for a move from car transport to walking and cycling, and have implications for empirical and modelling research.

Translating road safety into health outcomes using a quantitative impact assessment model

IntroductionThe majority of traffic safety policies are limited to preventing mortality. However, non-fatal injuries also impose a significant risk of adverse health. Therefore, both mortality and morbidity outcomes should be...

Estimating the global public health implications of electricity and coal consumption.

Background: The growing health risks associated with greenhouse gas emissions highlight the need for new energy policies that emphasize efficiency and low-carbon energy intensity.Objectives: We assessed the relationships among electricity use, coal consumption, and health outcomes.Methods: Using time-series data sets from 41 countries with varying development trajectories between 1965 and 2005, we developed an autoregressive model of life expectancy (LE) and infant mortality (IM) based on electricity consumption, coal consumption, and previous year’s LE or IM. Prediction of health impacts from the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) integrated air pollution emissions health impact model for coal-fired power plants was compared with the time-series model results.Results: The time-series model predicted that increased electricity consumption was associated with reduced IM for countries that started with relatively high IM (> 100/1,000 live births) and low LE (< 57 years) in 1965, whereas LE was not significantly associated with electricity consumption regardless of IM and LE in 1965. Increasing coal consumption was associated with increased IM and reduced LE after accounting for electricity consumption. These results are consistent with results based on the GAINS model and previously published estimates of disease burdens attributable to energy-related environmental factors, including indoor and outdoor air pollution and water and sanitation.Conclusions: Increased electricity consumption in countries with IM < 100/1,000 live births does not lead to greater health benefits, whereas coal consumption has significant detrimental health impacts.

Increasing fruit and vegetable consumption: a cost-effectiveness analysis of public policies

In many countries, consumption of fruits and vegetables (F&V) is below recommended levels. We quantify the economic and health effects of alternative policy (P) scenarios aiming to increase F&V consumption: (P1) 3.4% reduction in VAT, (P2) €100/year/person F&V stamp policy designed for low-income consumers (LIC) and (P3) €10 M information campaign. An economic model of the F&V market provides F&V consumption variations to a health impact model, leading to the number of deaths avoided (DA) and life-years saved (LYS). We compare the cost per statistical DA and LYS, taking into account the public costs of alternative policies. This analysis is applied to France in 2006. Relative risks of death for one additional F&V portion are disease dependent (range: 0.84-0.99). The highest variations in F&V consumption levels (less than +10 g/day/person on average) and health effects (<+600 DA, <+10 000 LYS) are modest. The costs/LYS are smaller for information campaign (€3 k), followed by VAT reduction (€99 k) and food stamp policy (€403 k). However, the information campaign leads to less LYS than VAT reduction. The food stamp policy reduces health inequalities between LIC and others, whereas the other ones can increase them. Our results suggest that (i) LYS are larger with VAT reduction than F&V stamps policies, (ii) information campaigns are the most cost-effective and (iii) market forces can limit the impacts of public health policies designed to favour F&V consumption increase.

Developing Methods for Estimating the Impacts of Climate Change on Malnutrition

ISEE-0403 Background: Climate change is likely to influence future crop productivity globally, with greatest vulnerability in developing nations. To date, assessments of the climate-change attributable impacts on “health” have focused on food availability and access to estimate ‘millions at risk of hunger' and have neglected malnutrition as an outcome. We developed a new model for estimating climate change-attributable burdens of malnutrition for the QUEST-GSI project (global-scale impacts of climate change: an integrated multi-sectoral assessment), part of the NERC-funded QUEST research programme on global change. Methods: GLAM global crop model (Walker Institute) estimates of future cereals yields were used to drive a food availability model (Southampton University) to provide estimates of future undernourishment at the country level. As malnutrition has multiple causes, stunting in children aged under 5 was estimated as a function of undernourishment (food-causes) and a GDP-derived development indicator (non-food causes) of stunting. A Bayesian approach for estimating the parameters of the health impact model was used by combining prior expert knowledge of the parameter values with current health outcome data observations. Results: The model outcome measures are proportion of population with stunting for five world regions (Sub-Saharan Africa and South Asia) under 4 SRES emissions scenarios. The proportion stunted was converted to DALYs following methods developed for the WHO global burden of disease assessment. Malnutrition burdens were estimated under three scenarios of improvements in agricultural technology. The main sources of uncertainty were described and quantified, where possible. Conclusion: Although the models indicate the burden of malnutrition is likely to increase under climate change, such estimates are very sensitive to model assumptions, and incorporate a large range of uncertainty from both the climate and socio-economic inputs and assumptions.