confounders saw no independent association...” Our Brazilian birth cohort studies examined several confounders including education, income, helminthiases, and anaemia. After controlling for these, early childhood diarrhoea and nutritional status still predicted cognitive function, but not independently of each other. Early childhood diarrhoea was a good, if not better, predictor of cognitive function than nutritional status. Much research on child development in developing countries addresses undernutrition, but fails to capture the effect that repeated dehydrating, malnourishing episodes of diarrhoea in the first years of life can have on cognitive potential—an effect that can persist despite catchup growth. Indeed, our follow-up studies show that early childhood diarrhoea and height-for-age Z scores at age 2 years predict impaired school performance.4 The message is that diarrhoea impairs nutritional status, and that both signal adverse risks for child development. Both warrant effective interventions, be they nutrition, sanitation, or treatment. We wholeheartedly agree with Walker and colleagues that intervention studies are needed to clarify these associations. Such studies are underway with trials of vitamin A, zinc, and glutamine among high-risk children in Brazil. Further work on the prevention and treatment of repeated enteric infections and nutritional shortfalls is badly needed. We declare that we have no conflict of interest.
*Sean R Moore, Breyette Lorntz, Aldo A M Lima, Richard L Guerrant
[email protected] Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Vanderbilt University, Nashville, TN 37232, USA (SRM); University of Virginia, Charlottesville, VA, USA (BL, RLG); and Clinical Research Unit, Federal University of Ceará, Fortaleza, Ceará, Brazil (AAML) 1
Walker SP, Wachs TD, Meeks Gardner J, et al. Child development: risk factors for adverse outcomes in developing countries. Lancet 2007; 369: 145–57.
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Guerrant DI, Moore SR, Lima AA, Patrick PD, Schorling JB, Guerrant RL. Association of early childhood diarrhea and cryptosporidiosis with impaired physical fitness and cognitive function four-seven years later in a poor urban community in northeast Brazil. Am J Trop Med Hyg 1999; 61: 707–13. Niehaus MD, Moore SR, Patrick PD, et al. Early childhood diarrhea is associated with diminished cognitive function 4 to 7 years later in children in a northeast Brazilian shantytown. Am J Trop Med Hyg 2002; 66: 590–93. Lorntz B, Soares AM, Moore SR, Pinkerton R, et al. Early childhood diarrhea predicts impaired school performance. Ped Infect Dis J 2006; 25: 513–20.
Coronary heart disease in Chile Health conditions in Chile have changed strikingly in the past half century. In a brief period of time, Chile has undergone deep demographic and epidemiological transitions. Life expectancy increased from 63·6 years (1970–75) to 77·7 years (2000–05). Infant mortality decreased from 120 to 7·8 per 1000 neonates (1960–2003). And chronic diseases have become the most important cause of death and loss of quality of life in the Chilean population.1 Cardiovascular disease is a major health problem. Deaths from acute myocardial infarction have increased over the past two decades, and although its lethality has declined in recent years,2 it still represents the leading cause of death among adults (7·5%). Ischaemic heart disease is the third cause of loss of disability-adjusted life years.3 The National Health Survey (ENS 2003)4 showed a high prevalence of risk factors among the general population: sedentary lifestyle (90·8%), cigarette smoking (42·0%), low HDLcholesterol concentrations (39·3%), hypercholesterolaemia (35·4%), hypertension (33·7%), and obesity (23·2%). 41% of the population had two or more major risk factors and 55% had a global cardiovascular risk classified as “high” or “very high”.5 What has Chile done about such a significant burden? A health reform is underway, which includes acute myo-
cardial infarction as one of 56 health conditions to be covered by the Explicit Health Guarantees System Bill—a law that guarantees access to health care, opportunity, quality, and financial protection for every citizen. This law established that anyone presenting with an acute coronary syndrome will have appropriate medical assessment and treatment, including secondary prevention medication at discharge. In terms of primary prevention, type 2 diabetes and essential hypertension have been included in the new bill; others such as smoking, obesity, and sedentary lifestyle have not so far. The Chilean experience reveals the importance of making a proper characterisation of coronary heart disease. This information is crucial for establishing adequate health objectives and reasonable strategies by which to accomplish them. Even though the management of acute coronary syndromes has improved in Chile, the burden of coronary heart disease will only be confronted holistically when emphasis is placed on primary prevention, including better control of risk factors and their psychosocial and environmental determinants.
The printed journal includes an image merely for illustration
We declare that we have no conflict of interest.
*Claudia Bambs, Jaime Cerda, Víctor Zárate
[email protected] Department of Cardiovascular Diseases (CB) and Department of Public Health (JC, VZ), Pontificia Universidad Católica de Chile, Santiago, Chile 1
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Department of Statistics and Health Information. Mortality by cause and gender, Chile, 2004. http://deis.minsal.cl/index.asp (accessed Jan 5, 2007). Corbalán R, Nazzal C, Prieto JC, et al. Reduction of acute myocardial infarction mortality in Chilean hospitals. Rev Med Chil 2002; 130: 368–78. Chilean Ministry of Health. Burden of disease in Chile. Santiago: Ministerio de Salud de Chile, 1996. Chilean Ministry of Health. National Population Health Survey (ENS 2003). Santiago: Ministerio de Salud de Chile, 2004. National Heart, Lung, and Blood Institute. Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Bethesda: National Institutes of Health, 2001.
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