The general aim of medicine is to reduce the burden of ill-health and mortality, such that individuals are able to enjoy longer, healthier lives. Indeed, advances in medicine have meant that life expectancy in most countries has increased by around 10 years in the past 40 years, albeit with large variation between the richest and poorest countries.

As a result of significant medical advances, the global population has continued to grow and age, but this has led to a broad shift in the type of diseases that cause the most burden; from communicable (i.e. infectious), maternal, neonatal and nutritional causes of death to non-communicable diseases (NCDs).

So what does this mean in terms of disease burden? On which diseases should we be focusing our attention and efforts in the post Millennium development goals era? And what are the challenges and opportunities that lie ahead? To discuss these important issues, BMC Medicine has launched a new series within the Medicine for Global Health collection, which focuses on the biggest global causes of premature mortality and morbidity.

The increasing burden of non-communicable diseases

NCDs in particular are becoming an increasing problem in terms of mortality. Also, as these diseases are mainly chronic, they lead to significant loss of healthy years of life, which places a considerable burden on individual quality of life, as well as on development and economic growth. Compared with the substantial progress in reduction of mortality over the past few years, relatively little progress has been made in reduction of the overall effect of non-fatal disease and injury on population health; although people are living longer, they may be living less healthily. In fact, NCDs now account for a startling 54% of the total global disease burden as measured by disability adjusted life years (DALYs).

Four such NCDs are cardiovascular disease, chronic obstructive pulmonary disease (COPD), cancer and diabetes, which are already well-recognised for causing much health-loss worldwide, and are sometimes collectively referred to as ‘the Big Four’. But do we pay these NCDs more attention at the expense of other NCDs? A recent news article would suggest this is indeed the case, for cancer at least. In fact, despite ‘the Big Four’ NCDs causing much of the health burden, over half the burden of NCDs arises from other NCDs. In a forum article, a panel of eight experts remind us that there are other NCDs that cause significant health burdens, which need to be brought out of the shadows.

Harms of heavy drinking

One such neglected NCD is liver cirrhosis, for which excessive alcohol consumption is responsible for around half the burden. A recent study estimating the global burden of liver cirrhosis found that it caused over 1 million deaths in 2010, with the highest mortality rates in Egypt and Moldova, suggesting that cirrhosis is a significant global health problem and measures to reduce risk factors should be reinforced in specific countries. In an accompanying commentary, Peter Byass commented on these new estimates, highlighting the challenges of this analysis and discussing the ways in which the data could be used for risk-reduction strategies.

Heavy drinking is a known risk factor for other NCDs, too. A systematic review and meta-analysis finds that, although low alcohol consumption without heavy drinking episodes reduces risk of ischaemic heart disease (IHD), individuals with alcohol use disorder have a 1.5-2 fold elevated risk of IHD.

Despite the risks associated with heavy drinking, it is still considered an ‘acceptable risk’. Jürgen Rehm and colleagues explore this conundrum in an Opinion article. Additionally, Sir Ian Gilmore, professor of hepatology with a particular interest in health harms related to alcohol misuse discusses the medical and public health aspects of excessive drinking in a video Q & A.

Tobacco-attributable mortality

Another lifestyle factor that can influence NCD risk is tobacco smoking. There is a very real prospect that rates of COPD, cancers and vascular diseases will rise in low- and middle-income countries as the full effects of uptake of smoking from decades ago reveals themselves. Alan Lopez, who co-developed the Peto-Lopez method, which is widely used to estimate tobacco-attributable mortality, talks to BMC Medicine about the changing burden of tobacco-attributable mortality across the world.

There are many challenges and opportunities in addressing the biggest risks to our health. It is hoped that heightened awareness of such issues, along with increased research, will help to address the growing burden of disease to enable lives that are both long and healthy.

All of these articles are part of BMC Medicine’s ‘Medicine for Global Health: Big Risks’ article collection, which has launched today and is now open for submissions. The collection aims to highlight the challenges and opportunities in addressing the biggest global causes of premature mortality. We welcome submission of articles focusing on measurement issues, financing options and development and delivery of interventions aimed at reducing the burden of these big risks. If you would like your latest research or reviews to be considered, please send a pre-submission query to bmcmedicineeditorial@biomedcentral.com.

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