NCDs--what's in an acronym?

Abstract

This issue contains the first of a set of eight articles on the current state and future prospects for epidemiology in the different regions of the globe. WHO Western Pacific Region (WPR) leads the series, comprising countries as populous as China and as remote as Kiribati, which makes summarizing the burden of disease, epidemiological training, resources and research and predicting the future a real challenge. Perhaps surprisingly, WPR has the lowest agestandardized disability-adjusted life years (DALYs) rate of all WHO regions, and even in lowand middle-income countries of WPR, two-thirds of DALYs lost are attributable to non-communicable diseases (NCDs). In terms of risk factors the epidemiologic transition is well established—alcohol, tobacco and high blood pressure are the top three risk factors, contributing over 20% of DALYs lost. Published epidemiology output is highest per head of population for New Zealand and, inexplicably, Micronesia, although China heads the field in terms of absolute numbers of publications. The authors emphasize the importance of reorientation of epidemiology training and research towards NCDs—a theme that I expect will recur in subsequent articles. The editors are very grateful to Cesar Victora (President-elect, IEA), Ahmed Mandil (Treasurer-elect, IEA) and Neil Pearce (President, IEA) for guest editing this series. NCDs are a hot topic at present in the run-up to the United Nations High Level Meeting on NCDs in September 2011. The only previous one—for HIV/ AIDS—was a decade ago and is generally viewed as a triumph of global health action. There is a growing consensus about what needs to be done for NCDs— leadership, prevention, treatment, monitoring and accountability and international cooperation and funding, but an overwhelming agenda, splits by disease factionalism, and an adverse funding climate may limit what can be achieved. Epidemiologists can make an important contribution in preparing the evidence for the UN High Level Meeting as shown in this issue by Dalal et al. who take a look at what we know about NCDs in sub-Saharan Africa. Reviewing the available literature they found published community-based studies in only 13 out of 45 sub-Saharan countries amounting to 94 papers about heart disease, stroke, diabetes and cardiovascular risk factors. These studies confirmed the high prevalence of risk factors, particularly hypertension. In an accompanying commentary, Saidi Kapiga emphasizes the inter-relationships between infectious diseases and NCDs and argues for taking action and not just conducting more surveys. Peer reviewers commenting on a grant proposal I made to integrate NCD risk factor surveillance and treatment with AIDS services in sub-Saharan Africa said there was no convincing evidence that NCDs are of importance in this region. There is now. It remains to be seen whether ‘NCDs’ will become a household term in the same way as AIDS has been adopted despite few people knowing what the acronym stands for these days. NCDs are a mixed bag and as a descriptive term defining disease groups by exclusion is unsatisfactory. Moreover, with a third of all cancers in sub-Saharan Africa attributable to infectious causes, it makes aetiological nonsense to lump all cancers into the NCD group. ‘Chronic diseases’ is no better as a term. Many presentations of these ‘chronic’ diseases are actually very acute— myocardial infarction, diabetic ketosis, asthma attacks and many infectious diseases are ‘chronic’. As is becoming apparent in current dialogues, the inclusion or exclusion of specific diseases is causing friction— should mental health, epilepsy and arthritis be in or out? NCDs for the purposes of the UN High Level Meeting now include cardiovascular diseases, cancers, diabetes and chronic obstructive lung disease, because these diseases make a dominant contribution to burdens of disease and, to an extent, share risk factors. So, despite the problems, we persist with NCDs. Maybe we should just revert to ‘diseases’— they are all important, they all need a functioning health system, most are preventable and older people, in particular, often experience several of them at once. A recent publication of global prevalence and trends since 1980 in obesity, indexed by body mass index (BMI), provoked concerns about tsunamis of cardiovascular disease, despite remarkably low levels of obesity in India and China. But have we been using the wrong metric all this time? Abdullah et al. have used the Framingham cohort study which has updated measures of BMI every 2 years for almost 50 years. They find that the number of years lived with obesity is an independent, dose–response Published by Oxford University Press on behalf of the International Epidemiological Association