Disease proportions attributable to environment

Population disease proportions attributable to various causal agents are popular as they present a simplified view of the contribution of each agent to the disease load. However they are only summary figures that may be easily misinterpreted or over-interpreted even when the causal link between an exposure and an effect is well established. This commentary discusses several issues surrounding the estimation of attributable proportions, particularly with reference to environmental causes of cancers, and critically examines two recently published papers. These issues encompass potential biases as well as the very definition of environment and of environmental agent. The latter aspect is not just a semantic question but carries implications for the focus of preventive actions, whether centred on the material and social environment or on single individuals

The impact of the environment on health by country: a meta-synthesis

<p>Abstract</p> <p>Background</p> <p>Health gains that environmental interventions could achieve are main questions when choosing environmental health action to prevent disease. The World Health Organization has recently released profiles of environmental burden of disease for 192 countries.</p> <p>Methods</p> <p>These country profiles provide an estimate of the health impacts from the three major risk factors 'unsafe water, sanitation & hygiene', 'indoor air pollution from solid fuel use' and 'outdoor air pollution'. The profiles also provide an estimate of preventable health impacts by the environment as a whole. While the estimates for the three risk factors are based on country exposures, the estimates of health gains for total environmental improvements are based on a review of the literature supplemented by expert opinion and combined with country health statistics.</p> <p>Results</p> <p>Between 13% and 37% of the countries' disease burden could be prevented by environmental improvements, resulting globally in about 13 million deaths per year. It is estimated that about four million of these could be prevented by improving water, sanitation and hygiene, and indoor and outdoor air alone. The number of environmental DALYs per 1000 capita per year ranges between 14 and 316 according to the country. An analysis by disease group points to main preventions opportunities for each country.</p> <p>Conclusion</p> <p>Notwithstanding the uncertainties in their calculation, these estimates provide an overview of opportunities for prevention through healthier environments. The estimates show that for similar national incomes, the environmental burden of disease can typically vary by a factor five. This analysis also shows that safer water, sanitation and hygiene, and safer fuels for cooking could significantly reduce child mortality, namely by more than 25% in 20 of the lowest income countries.</p

Children's environmental health: an under-recognised area in paediatric health care

The knowledge that the environment in which we live, grow and play, can have negative or positive impacts on our health and development is not new. However the recognition that adverse environments can significantly and specifically affect the growth and development of a child from early intrauterine life through to adolescence, as well as impact their health later in adulthood, is relatively recent and has not fully reached health care providers involved in paediatric care

Open defecation and childhood stunting in India: an ecological analysis of new data from 112 districts.

Poor sanitation remains a major public health concern linked to several important health outcomes; emerging evidence indicates a link to childhood stunting. In India over half of the population defecates in the open; the prevalence of stunting remains very high. Recently published data on levels of stunting in 112 districts of India provide an opportunity to explore the relationship between levels of open defecation and stunting within this population. We conducted an ecological regression analysis to assess the association between the prevalence of open defecation and stunting after adjustment for potential confounding factors. Data from the 2011 HUNGaMA survey was used for the outcome of interest, stunting; data from the 2011 Indian Census for the same districts was used for the exposure of interest, open defecation. After adjustment for various potential confounding factors--including socio-economic status, maternal education and calorie availability--a 10 percent increase in open defecation was associated with a 0.7 percentage point increase in both stunting and severe stunting. Differences in open defecation can statistically account for 35 to 55 percent of the average difference in stunting between districts identified as low-performing and high-performing in the HUNGaMA data. In addition, using a Monte Carlo simulation, we explored the effect on statistical power of the common practice of dichotomizing continuous height data into binary stunting indicators. Our simulation showed that dichotomization of height sacrifices statistical power, suggesting that our estimate of the association between open defecation and stunting may be a lower bound. Whilst our analysis is ecological and therefore vulnerable to residual confounding, these findings use the most recently collected large-scale data from India to add to a growing body of suggestive evidence for an effect of poor sanitation on human growth. New intervention studies, currently underway, may shed more light on this important issue

Factors that impact on access to water and sanitation for older adults and people with disability in rural South Africa: An occupational justice perspective

Limited access to water and sanitation is a risk to health, dignity, and ability to engage in occupations. This article aims to: 1) discuss the current and historical factors affecting access to water and sanitation in rural South Africa, and 2) explore the occupational implications of water access, particularly for older adults and people with disability in rural South Africa. A literature review was carried out through searching JSTOR, Scopus, and MEDLINE databases and using framework analysis to interpret the retrieved documents. This paper also reports a thematic analysis of semi-structured interviews, conducted in 2012 in a rural area of South Africa. Environmental, political, social-economic and attitudinal factors were identified as impacting water access and occupation, in both the documentary analysis and the semi-structured interviews. Due to South Africa’s history, injustice has occurred in the forms of occupational apartheid and occupational deprivation. We argue that supply systems must enable people to easily access more water than is essential for survival, so that people can participate in meaningful and productive occupations. Therefore, access to water should be considered part of an occupational right. Recognising this right will be an integral step in ensuring that water supplies are improved to support better livelihoods, and to achieve economic and social empowerment, and quality of life for all, in line with many of the United Nations’ new Sustainable Development Goals

Economic Aspects of Sanitation in Developing Countries

Improved sanitation has been shown to have great impacts on people's health and economy. However, the progress of achieving the Millennium Development Goals (MDGs) on halving the proportion of people without access to clean water and basic sanitation by 2015 has thus far been delayed. One of the reasons for the slow progress is that policy makers, as well as the general public, have not fully understood the importance of the improved sanitation solutions. This paper, by gathering relevant research findings, aims to report and discuss currently available evidence on the economic aspects of sanitation, including the economic impacts of unimproved sanitation and the costs and economic benefits of some common improved sanitation options in developing countries.; DATA USED IN THIS PAPER WERE OBTAINED FROM DIFFERENT INFORMATION SOURCES: international and national journal articles and reports, web-based statistics, and fact sheets. We used both online search and hand search methods to gather the information.; Scientific evidence has demonstrated that the economic cost associated with poor sanitation is substantial. At the global level, failure to meet the MDG water and sanitation target would have ramifications in the area of US$38 billion, and sanitation accounts for 92$142 billion (US$year 2005). This translates to a per capita spending of US$28 for sanitation. Annually, this translates to roughly US$14 million. The evidence complied in this paper demonstrates that investing in sanitation is socially and economically worthwhile. For every US$1 invested, achieving the sanitation MDG target and universal sanitation access in the non-OECD countries would result in a global return of US$9.1 and US$11.2, respectively.; Given the current state of knowledge, sanitation is undeniably a profitable investment. It is clear that achieving the MDG sanitation target not only saves lives but also provides a foundation for economic growth

Broader health coverage is good for the nation's health: evidence from country level panel data.

Progress towards universal health coverage involves providing people with access to needed health services without entailing financial hardship and is often advocated on the grounds that it improves population health. The paper offers econometric evidence on the effects of health coverage on mortality outcomes at the national level. We use a large panel data set of countries, examined by using instrumental variable specifications that explicitly allow for potential reverse causality and unobserved country-specific characteristics. We employ various proxies for the coverage level in a health system. Our results indicate that expanded health coverage, particularly through higher levels of publicly funded health spending, results in lower child and adult mortality, with the beneficial effect on child mortality being larger in poorer countries

The Costs of Climate Change: A Study of Cholera in Tanzania

Increased temperatures and changes in rainfall patterns as a result of climate change are widely recognized to entail potentially serious consequences for human health, including an increased risk of diarrheal diseases. This study integrates historical data on temperature and rainfall with the burden of disease from cholera in Tanzania and uses socioeconomic data to control for the impacts of general development on the risk of cholera. The results show a significant relationship between temperature and the incidence of cholera. For a 1 degree Celsius temperature increase the initial relative risk of cholera increases by 15 to 29 percent. Based on the modeling results, we project the number and costs of additional cases of cholera that can be attributed to climate change by 2030 in Tanzania for a 1 and 2 degree increase in temperatures, respectively. The total costs of cholera attributable to climate change are shown to be in the range of 0.32 to 1.4 percent of GDP in Tanzania 2030. The results provide useful insights into national-level estimates of the implications of climate change on the health sector and offer information which can feed into both national and international debates on financing and planning adaptation