Chronic diseases: an increasing challenge in developing countries

The health of the populations of all but the poorest developing countries has improved markedly over the past four decades. As a result, life expectancy in developing countries is converging with that in developed countries, and the world average is currently about 65 years. Now only 4% of the world's population lives in countries where life expectancy is less than 50, compared with 60% in 1960. These huge health gains are often overshadowed in the public's mind by the massive, high-profile disasters of HIV and AIDS, preventable childhood diseases, malaria and tuberculosis. Yet chronic diseases present an even greater threat to health in most low-middle income countries: particularly heart disease, diabetes, cancers and chronic respiratory diseases, which are driven by unhealthy consumption patterns. Together, they account for more than 50% of all deaths worldwide. In absolute numbers, there are twice as many deaths from cardiovascular disease (CVD) in developing countries as in developed countries. However, financial and political support for both action and research into chronic diseases continue to be severely neglected (Yach et al., 2004), just as their harmful impact on health and economies is increasing (Leeder et al., 2004). Omission of chronic diseases from the Millennium Development Goals (MDG) – now seen as the priorities for global health investment – confuses donors and politicians alike and could set back chronic disease prevention and control for decades. While MDG are appropriate for the poorest 1 billion in the world, the 4 billion people living in low-middle income countries have a health profile today that requires addressing chronic diseases and risks. Tobacco, diet and physical activity account for much of the burden of chronic diseases in countries at all levels of development (WHO, 2002; Yusuf et al., 2004). About 1.3 billion people use tobacco, and nearly 1 billion people in the world are overweight or obese. Tobacco use over the last few decades has led to 5 million deaths annually. These factors are among the 10 leading contributors to the total burden of disease and are common in most countries. In recent years, epidemiological research in developing countries such as China have shown that tobacco (Lam et al., 2001) and body mass index (Ni Mhurchu et al. Asia Pacific Cohort, 2004) have the same impacts on chronic disease outcomes as earlier research indicated in developed countries. As people in developing countries get fatter and smoke more, they will die younger of preventable diseases. It is a common misconception that obesity and tobacco use are solely the problem of developed countries. Not only are large, rapidly developing countries such as Brazil, South Africa, India and China facing steadily increasing rates of chronic diseases, but so are smaller countries such as Cameroon, Tanzania and the Pacific island nation of the Federated States of Micronesia (FSM). About 80% of all FSM citizens aged 35–55, and a comparable percentage of this age cohort in the Marshall Islands, can be defined as obese. This is double the rate of 38% obesity found in the US population. Rates of hypertension and diabetes in these island nations are likewise much higher than in the US: 35 and 20% vs. 20 and 7%, respectively (Hezel, 2004). Tobacco use is also rising in developing countries: over 60% of men in China smoke, as opposed to just over 20% in the US. Another common misconception is that chronic diseases affect only the affluent, yet risks are accruing among populations of low socio-economic states. In developed countries, risk factor exposure is directly associated with poverty, social class and level of education. These risks have led to a higher rate of chronic diseases among poorer populations, not only in the US but also in most of Europe. In developing countries, the poorest populations already exhibit the highest risks for tobacco use and alcohol. Recent work in Brazil indicates that, over time, female obesity shifts toward lower income groups in economically more developed regions and urban areas. In Jamaica, the highest rates of diabetes and obesity are found among the country's poorest women (Yach and Hawkes, 2004). Chronic diseases have a significant economic impact in developing countries by disabling and killing the working-age population (Leeder et al., 2004). This is manifested in rising health, social security and pension costs, and the loss of productive years. Popkin estimated that in 1995 diet-related chronic diseases alone accounted for 22.6 and 13.9% of government health care costs in China and India, respectively, while the estimated cost of lost productivity was 0.5 and 0.7% of the gross domestic product, respectively (Popkin et al., 2001). These effects could have serious global impacts. If chronic diseases diminish productivity as predicted, then investor returns in developing countries will be affected, impacting growth in countries that provide developmental aid (Heller, 2003; Kimmis et al., 2002). As with HIV and AIDS, chronic conditions also place heavy financial burdens on companies, especially when treatment is expensive. Moreover, a continued rise in chronic diseases could threaten a window of opportunity for low-middle income countries to gain long-term economic benefit over the next 20 years from the demographic changes that are taking place. In many of these countries, the number of children under 5 years will decline steadily, while the number of adults over 65 will not rise markedly. These countries can strengthen their economic capacity for the future at a time when they need fewer resources to support dependents. If countries act now to decrease tobacco use and promote physical activity and healthy diet, there will be lower disability rates in people over 65, which will place less strain on the health systems and national budget (Leeder et al., 2004). However, low-middle income countries face unique obstacles in pursuing these health gains. Several aspects of globalization have the potential to increase the rate of chronic diseases, particularly in developing countries. These include trade, foreign direct investment and marketing to children. Tobacco trade has increased consumption in many countries (Bettcher et al., 2003). Foreign direct investment in tobacco, food and alcohol may bring with it pressures that weaken the ability of governments to introduce effective regulatory, fiscal and educational measures to promote health (Bolling et al., 1998; Yach et al., 2004). Global marketing (along with other influences) promotes the use of tobacco and alcohol and influences dietary habits (Hastings et al., 2003) in children, currently for the worse. There is a paucity of research conducted on chronic diseases by researchers in developing countries. Authors from the US and the UK dominate research output in all disease and risk categories, accounting for 60–80% of research on tobacco and cancer, diabetes and CVD. India and China produce less than 3.5% in all categories, despite being home to 40% of the world's population and a large share of the chronic disease burden (Yach, 2004). What interventions have been most successful in reducing rates of chronic diseases and what research is needed? Reports have shown that select clinically based primary care interventions that focus on people at elevated risk for chronic disease reduce the complication and death rates from CVD and diabetes. This particularly applies to smoking cessation and the expanded use of anti-hypertensive drugs and aspirin. These interventions are the adult equivalent of low-cost, highly effective interventions that could prevent nearly two-thirds of childhood deaths (The Bellagio Study Group on Child Survival, 2003). Applied research is needed to assess the effectiveness of these interventions and to monitor the trends in risk factors in developing countries (Yach, 2004). Health promotion and chronic disease prevention research projects are also necessary. The WHO recommends that international partnerships for research be established to facilitate this work (Pang et al., 2004). The Oxford Vision 2020 movement is pioneering community-based intervention projects in developing countries facilitated by academics, private companies, non-governmental organizations and governments (Oxford Vision 2020, 2005). Community-based projects harness the diverse talents of multi-sectored stakeholders to reduce the burden of chronic diseases. Health professionals and academics implement clinical prevention programs and provide training and evaluative measures. Community leaders and non-profit organizations must prepare the community for action. Governments advance policies and programs that encourage physical exercise and a healthy diet, while imposing disincentives such as taxes on tobacco use (Puska et al., 1995). While funding can come through traditional routes, such as governments and funding agencies, new private sources of support should be encouraged, such as food, pharmaceutical and insurance companies, as well as labor unions. These stakeholders realize that chronic diseases impose a serious economic burden that will increasingly affect their success. At the national and local levels, health professionals and other stakeholders need to capitalize on the international momentum in the field and take action to prevent chronic diseases through research and interventions. Action to divert the course of chronic disease risk factors is being taken at the international level through the adoption of two major WHO strategies: the Framework Convention on Tobacco Control (FCTC), adopted in 2003, and the Global Strategy on Diet, Physical Activity and Health (Global Strategy), adopted in 2004 (WHO 2003, 2004). Health professionals, through strong non-governmental organizations such as the International Obesity Taskforce, International Diabetes Federation, World Heart Federation, International Cancer Union, International Council of Nurses and World Medical Association, need to be more assertive and engaged in supporting these strategies. There must be a concerted global effort to make healthy choices the easy choices.