Impact of Dietary and Metabolic Risk Factors on Cardiovascular and Diabetes Mortality in South Asia: Analysis From the 2010 Global Burden of Disease Study.

OBJECTIVES: To quantify cardiovascular disease and diabetes deaths attributable to dietary and metabolic risks by country, age, sex, and time in South Asian countries. METHODS: We used the 2010 Global Burden of Disease national surveys to characterize risk factor levels by age and sex. We derived etiological effects of risk factors-disease endpoints, by age, from meta-analyses. We defined optimal levels. We combined these inputs with cause-specific mortality rates to compute population-attributable fractions as a percentage of total cardiometabolic deaths. RESULTS: Suboptimal diet was the leading cause of cardiometabolic mortality in 4 of 5 countries, with population-attributable fractions from 40.7% (95% uncertainty interval = 37.4, 44.1) in Bangladesh to 56.9% (95% uncertainty interval = 52.4, 61.5) in Pakistan. High systolic blood pressure was the second leading cause, except in Bangladesh, where it superseded suboptimal diet. This was followed in all nations by high fasting plasma glucose, low fruit intake, and low whole grain intake. Other prominent burdens were more variable, such as low intake of vegetables, low omega-3 fats, and high sodium intake in India, Nepal, and Pakistan. CONCLUSIONS: Important similarities and differences are evident in cardiometabolic mortality burdens of modifiable dietary and metabolic risks across these countries, informing health policy and program priorities.

The science of epidemiology and the methods needed for public health assessments: a review of epidemiology textbooks.

OBJECTIVES: Epidemiology is often described as 'the science of public health'. Here we aim to assess the extent that epidemiological methods, as covered in contemporary standard textbooks, provide tools that can assess the relative magnitude of public health problems and can be used to help rank and assess public health priorities. STUDY DESIGN: Narrative literature review. METHODS: Thirty textbooks were grouped into three categories; pure, extended or applied epidemiology, were reviewed with attention to the ways the discipline is characterised and the nature of the analytical methods described. RESULTS: Pure texts tend to present a strict hierarchy of methods with those metrics deemed to best serve aetiological inquiry at the top. Extended and applied texts employ broader definitions of epidemiology but in most cases, the metrics described are also those used in aetiological inquiry and may not be optimal for capturing the consequences and social importance of injuries and disease onsets. CONCLUSIONS: The primary scientific purpose of epidemiology, even amongst 'applied' textbooks, is aetiological inquiry. Authors do not readily extend to methods suitable for assessing public health problems and priorities.

Why my disease is important: metrics of disease occurrence used in the introductory sections of papers in three leading general medical journals in 1993 and 2003.

BACKGROUND: We assessed the metrics used in claims about disease importance made in the introductory sections of scientific papers published in 1993 and 2003. We were interested in the choice of metric in circumstances where establishing the relative social importance of a disease was, presumptively, a primary objective. METHODS: This study consisted of a textual examination of the introductory statements from papers retrieved from MEDLINE. Papers were published in the New England Journal of Medicine, The Lancet, and the Journal of the American Medical Association during the first halves of 1993 and 2003, and were selected on the basis of keywords found in a pilot study to be associated with claims about disease importance. RESULTS: We found 143 papers in 1993 and 264 papers in 2003 included claims about disease importance in their introductory sections, and characteristics of these claims were abstracted. Of the quotes identified in the papers and articles examined, most used counts, prevalence, or incidence measurements. Some also used risk estimates and economic quantities to convey the importance of the disease. There was no change in the types of metrics used between 1993 and 2003. Very few articles, even in 2003, used metrics that weighted disease onsets by the expected consequent loss of healthy time -- such as years of life lost, quality-adjusted life years, and/or disability-adjusted life years. CONCLUSIONS: Claims about the relative importance of diseases continued to be overwhelmingly expressed in terms of counts (of deaths and disease onsets) and comparisons of counts, rates, and risks. Where the aim is to convey the burden that a given disease imposes on a society, "event-based" metrics might be less fit for the purpose than "time-based" metrics. More attention is needed to how the choice of metric should relate to the purpose at hand.

Mortality attributable to excess adiposity in England and Wales in 2003 and 2015: explorations with a spreadsheet implementation of the Comparative Risk Assessment methodology.

BACKGROUND: Our aim was to estimate the burden of fatal disease attributable to excess adiposity in England and Wales in 2003 and 2015 and to explore the sensitivity of the estimates to the assumptions and methods used. METHODS: A spreadsheet implementation of the World Health Organization's (WHO) Comparative Risk Assessment (CRA) methodology for continuously distributed exposures was used. For our base case, adiposity-related risks were assumed to be minimal with a mean (SD) BMI of 21 (1) Kg m-2. All cause mortality risks for 2015 were taken from the Government Actuary and alternative compositions by cause derived. Disease-specific relative risks by BMI were taken from the CRA project and varied in sensitivity analyses. RESULTS: Under base case methods and assumptions for 2003, approximately 41,000 deaths and a loss of 1.05 years of life expectancy were attributed to excess adiposity. Seventy-seven percent of all diabetic deaths, 23% of all ischaemic heart disease deaths and 14% of all cerebrovascular disease deaths were attributed to excess adiposity. Predictions for 2015 were found to be more sensitive to assumptions about the future course of mortality risks for diabetes than to variation in the assumed trend in BMI. On less favourable assumptions the attributable loss of life expectancy in 2015 would rise modestly to 1.28 years. CONCLUSION: Excess adiposity appears to contribute materially but modestly to mortality risks in England and Wales and this contribution is likely to increase in the future. Uncertainty centres on future trends of associated diseases, especially diabetes. The robustness of these estimates is limited by the lack of control for correlated risks by stratification and by the empirical uncertainty surrounding the effects of prolonged excess adiposity beginning in adolescence.

Food, livestock production, energy, climate change, and health.

Food provides energy and nutrients, but its acquisition requires energy expenditure. In post-hunter-gatherer societies, extra-somatic energy has greatly expanded and intensified the catching, gathering, and production of food. Modern relations between energy, food, and health are very complex, raising serious, high-level policy challenges. Together with persistent widespread under-nutrition, over-nutrition (and sedentarism) is causing obesity and associated serious health consequences. Worldwide, agricultural activity, especially livestock production, accounts for about a fifth of total greenhouse-gas emissions, thus contributing to climate change and its adverse health consequences, including the threat to food yields in many regions. Particular policy attention should be paid to the health risks posed by the rapid worldwide growth in meat consumption, both by exacerbating climate change and by directly contributing to certain diseases. To prevent increased greenhouse-gas emissions from this production sector, both the average worldwide consumption level of animal products and the intensity of emissions from livestock production must be reduced. An international contraction and convergence strategy offers a feasible route to such a goal. The current global average meat consumption is 100 g per person per day, with about a ten-fold variation between high-consuming and low-consuming populations. 90 g per day is proposed as a working global target, shared more evenly, with not more than 50 g per day coming from red meat from ruminants (ie, cattle, sheep, goats, and other digastric grazers).

The contribution of leading diseases and risk factors to excess losses of healthy life in Eastern Europe: burden of disease study.

BACKGROUND: The East/West gradient in health across Europe has been described often, but not using metrics as comprehensive and comparable as those of the Global Burden of Disease 2000 and Comparative Risk Assessment studies. METHODS: Comparisons are made across 3 epidemiological subregions of the WHO region for Europe--A (very low child and adult mortality), B (low child and low adult mortality) and C (low child and high adult mortality)--with populations in 2000 of 412, 218 and 243 millions respectively, and using the following measures: 1. Probabilities of death by sex and causal group across 7 age intervals; 2. Loss of healthy life (DALYs) to diseases and injuries per thousand population; 3. Loss of healthy life (DALYs) attributable to selected risk factors across 3 age ranges. RESULTS: Absolute differences in mortality are most marked in males and in younger adults, and for deaths from vascular diseases and from injuries. Dominant contributions to east-west differences come from the nutritional/physiological group of risk factors (blood pressure, cholesterol concentration, body mass index, low fruit and vegetable consumption and inactivity) contributing to vascular disease and from the legal drugs--tobacco and alcohol. CONCLUSION: The main requirements for reducing excess health losses in the east of Europe are: 1) favorable shifts in all amenable vascular risk factors (irrespective of their current levels) by population-wide and personal measures; 2) intensified tobacco control; 3) reduced alcohol consumption and injury control strategies (for example, for road traffic injuries). Cost effective strategies are broadly known but local institutional support for them needs strengthening.

Impact of a reduced red and processed meat dietary pattern on disease risks and greenhouse gas emissions in the UK: a modelling study.

OBJECTIVES: Consumption of red and processed meat (RPM) is a leading contributor to greenhouse gas (GHG) emissions, and high intakes of these foods increase the risks of several leading chronic diseases. The aim of this study was to use newly derived estimates of habitual meat intakes in UK adults to assess potential co-benefits to health and the environment from reduced RPM consumption. DESIGN: Modelling study using dietary intake data from the National Diet and Nutrition Survey of British Adults. SETTING: British general population. METHODS: Respondents were divided into fifths by energy-adjusted RPM intakes, with vegetarians constituting a sixth stratum. GHG emitted in supplying the diets of each stratum was estimated using data from life-cycle analyses. A feasible counterfactual UK population was specified, in which the proportion of vegetarians measured in the survey population doubled, and the remainder adopted the dietary pattern of the lowest fifth of RPM consumers. OUTCOME MEASURES: Reductions in risks of coronary heart disease, diabetes and colorectal cancer, and GHG emissions, under the counterfactual. RESULTS: Habitual RPM intakes were 2.5 times higher in the top compared with the bottom fifth of consumers. Under the counterfactual, statistically significant reductions in population aggregate risks ranged from 3.2% (95% CI 1.9 to 4.7) for diabetes in women to 12.2% (6.4 to 18.0) for colorectal cancer in men, with those moving from the highest to lowest consumption levels gaining about twice these averages. The expected reduction in GHG emissions was 0.45 tonnes CO(2) equivalent/person/year, about 3% of the current total, giving a reduction across the UK population of 27.8 million tonnes/year. CONCLUSIONS: Reduced consumption of RPM would bring multiple benefits to health and environment.

The effect of ambient temperature on blood pressure in a rural West African adult population: a cross-sectional study.

INTRODUCTION: Associations between ambient temperature and blood pressure have been demonstrated in countries where the temperature varies between the seasons. This phenomenon has been overlooked in blood pressure surveys in sub-Saharan Africa. We assessed the effect of ambient temperature on blood pressure in an adult population in a West African country. METHODS: A cross-sectional survey was carried out on a rural Ghanaian population, investigating the effect of ambient temperature on blood pressure in 574 randomly sampled adults aged between 18 and 65 years. RESULTS: There was a significant inverse relationship between ambient temperature and systolic (SBP) (p < 0.019) and diastolic blood pressure (DBP) (p < 0.036). SBP fell by 5 mmHg per 10 degrees C rise in ambient temperature. CONCLUSION: Higher ambient temperatures are associated with lower blood pressures. To enhance comparability of data from epidemiological surveys, ambient temperature should be recorded for each blood pressure reading and findings standardised to a fixed ambient temperature.

Public understanding of the causes of high stroke risk in northeast Bulgaria.

BACKGROUND: Knowledge of stroke risk factors is undocumented in Bulgaria. METHODS: 188 subjects in 2000 and 447 in 2003 were asked: 'Why do you think stroke is so common in this region?' RESULTS: Stress and poverty accounted for 69% of the first mentions in 2000 and 59% in 2003. There were no mentions of high blood pressure and no first mentions of smoking in 2000. High blood pressure appears only 10 times and smoking 12 times among 745 answers in 2003. CONCLUSION: Health education on the established causes of stroke is an urgent priority in Bulgaria.