Friday, October 16, 2009

Chronic Disease in the United States (and the World)

When media headlines are dominated by the economy, global warming and terrorism, it is imperative that we step back from "the hype" and turn to actual data to reveal what really are the greatest challenges we face.

This chart from the Centers For Disease Control and Prevention ought to make the headlines of the evening news every single evening (since it doesn't, it headlines this blog for tonight!).

Reporting on reality is not entertaining, hence why little attention is paid to chronic disease. But this blog does not aspire to entertain (which no doubt severely limits its readership! :)). So I will provide us with "the facts". And hopefully this will stimulate new insights to help us get serious about today's challenges.

Consider this-- in the year 2005 the total deaths caused by the three leading causes of death in the United States (heart disease, cancer and stroke) far outnumber the complete category of "unintentional deaths". For every person who dies in a car crash, plane crash or workplace accident, etc., 100 people die from one of these three chronic diseases. The next time you see a media story about a hiker who died in a remote mountain, or a person being malled by a tiger at a zoo, just bear in mind how many more deaths occur from chronic disease every single day and go unreported.

Furthermore, and it is imperative that we recognise this, most chronic diseases afflict the aged.

So most of the people who died from heart disease, cancer or stroke were over the age of 65. More than three quarters of cancer deaths (76%) occur in people aged 65 years and over (source). According to the American Heart Association, over 83 percent of Americans who die of coronary heart disease are age 65 or older (source).

Aging causes most disease and death and yet we spend a minute fraction of public funds studying the biological processes of aging compared to the vast amounts spent on national defence and trying to control the climate and the economy. Gaining some control over the biological clocks we have inherited from our evolutionary past would yield enormous health and economic dividends. Age retardation might prove to be one of the most optimal ways to prevent chronic disease. Yet the social and political obstacles that impede this vision of preventative medicine are perhaps even bigger obstacles than the scientific ones aging researchers face.

One last point. Many of you are probably thinking "yeah, yeah, aging and chronic disease are problems in rich America. But what about the rest of the world? Surely infectious diseases like HIV and malaria and poverty kill more people than chronic disease". Well, if you are inclined to think that you should think again. Yes, HIV, malaria and poverty are very serious problems in poorer countries. But chronic diseases kill far more people. In lower middle income countries like China and India the World Health Organization estimates that chronic diseases are estimated to account for 75% of all deaths over the coming decade (source). And chronic diseases are on the rise in the poorest countries in the world (see here).

The 21st century is set to be the century of chronic disease. To meet the challenges of chronic disease we need to understand the ultimate (or evolutionary) and not just proximate causes, of these diseases. Hence why aging research should be among our top priorities for a new global health initiative. One with more health, less disease, disability and suffering, and greater economic prosperity for all. That's a world worth fighting for! To achieve it we must overcome the vulnerabilities of evolutionary neglect.