The bizarre chain of events in the UK of late, where protest gave way to riot, which yielded to brazen arson and looting, has given people plenty to chew over. Early commentators have noted that the perpetrators are not just the ‘obvious’ or the ‘usual suspects’, but a more diverse mixture with various motivations. It will be interesting to see in the long run whether clear trends and patterns emerge of who did what and why, but the most important question is ‘what can be done to prevent it happening again?’ Untangling the complex causes of a dynamic situation is difficult, and formulating appropriate policy responses is a challenge.
Modern day epi can be a bit like that. Our predecessors managed to nail a lot of the single cause-> single disease relationships (darn those pesky trailblazers!). This leaves our generation the head-scratching task of understanding the complex patterns of health and illness that occur once people stop dying in childhood and young adulthood of communicable disease.
Take obesity. Why does someone become morbidly obese? Lack of exercise? Poor diet? Bad genes? In each individual case we might see a different degree of contribution from each of those factors. But that doesn’t help us develop a policy response to tackle the problem.
Why does someone fail to do enough exercise? Are there a lack of safe and affordable opportunities in their neighbourhood? Are there cultural influences that deter an active lifestyle? Are there too many competing demands on their time such that the chance doesn’t appear to be available? Answers to these may highlight further areas of uncertainty such that we end up looking for the causes of the causes, and it all gets a bit Swiftian.
And why do different cases of a disease pan out differently? How much individual variation is there? What happens when a person has two diseases – how do these interact? To what extent do inequalities in access to care explain differences in outcomes between people or regions? And what can we do about any of this?
Perhaps the key to translating epidemiological insights into effective policy is to keep asking ‘why?’ until there are no more questions. It shouldn’t come as a surprise that complex problems have complex solutions and require complex interventions. Those making knee-jerk suggestions about how to sort out the current tensions would do well to be mindful that hurried policy changes can do more harm than good, and may just shift the problem to a different point in the chain. In the management of civil unrest and chronic disease, we need to be able to look at both the fine detail and the bigger picture.