Tuesday, December 01, 2009

Health Innovations: Safety and Equality

This post brings together a number of issues I have been working on with respect to aging research.

In particular, I am interested in why so many people tend to eschew the field of biogerontology, and often express worries or concerns that really are (upon reflection) inappropriate, inconsistent or disproportionate given the nature of the stakes typically involved (e.g. the high risks of morbidity and mortality associated with the aging "status quo"). To bring these issues to the fore consider the following...

Many scientific studies demonstrate that health innovation X (I will conceal the details of what X is until later on) can reduce our risk of disease and increase life expectancy. X reduces, for example, the risk of cardiovascular disease, the #1 killer in the United States. Some estimate that a steady intake of X can actually add between 1-4 years to a person's life expectancy.

But there is a down side. Firstly, X also has some risks of harm. Some of these risks are very low, but others are high. For the most minor of harms, like discomfort (or even mild pain), fatigue, sweating and muscle and joint pain, these usually accompany taking X (though they are not long-lasting).

But X can also cause more severe harms. There is some basis for believing that X can be addictive. Furthermore, there are thousands of cases of X causing death. X1, for example, is a very popular version of X. In the United States millions of people regularly take X1 each week. X1 is a popular and cheap form of X. Sadly, more than 500,000 people in the US who take X1 are treated in emergency departments every year, and more than 700 people die as a result of X1. (source)

Even more tragically, children are at particularly high risk of injury by taking X1. Children 15 years and younger accounted for 59% of all the X1 injuries seen in US emergency departments. Now there are things we can do to mitigate some of these harms, but X1 is intrinsically risky. The only way to prevent any deaths from X1 would be to prohibit X1. But no one would propose that.

The proper administration of X could reduce many of the risks I have outlined above. But there is no way to completely eliminate the risks associated with X.

Let me now turn, just briefly, to concerns of equality. X is not equally accessible to everyone. Some people, because of where they live, or their family situation (single parent, etc.), or their income, or their education, or their job, have greater access to X than others. And this inequality in access to X can have a profound impact on a person's risk of disease and death. Having regular and easy access to X can make the difference between suffering a heart attack and dying at 65 or enjoying a healthy retirement. So having access to X really is a matter of life and death.

OK, so what we know about X is that (a) it can have enormous health benefits for both populations and individuals. The regular utilization of X can reduce the risk of disease and increase life expectancy. We also know (b) that X has some adverse side-effects, ranging from injury (which is common) to addiction and even death. And we know (c) that X is not equally available to all people. So what should we do?

Some might think that X is only imaginary. "Surely", one might conjecture, "if X kills people, including children, it would be banned!". Or the egalitarian might argue that "X should be equally accessible to all, and if it isn't, then no one should have access to X". These are common intuitions. Let's see how they fare when I reveal that the case in hand is a real one....

OK, let me now tell you what X is.................................... X is EXERCISE!!

Regular exercise is an important health intervention that can help reduce our risks of morbidity and mortality and extend life. But exercise is intrinsically risky. As long as bikes share roads with cars (bike riding was X1) there will be bike fatalities. But even if cars didn't exist, people can still fall off of bikes, or drop weights on their heads, get hit by lightening while playing baseball, suffer a heart attack or dehydration while running a marathon, sprain ankles, pull muscles, etc., etc., etc.

Do a "google" image search for "sports injuries" to see some of the 16 000 000 images (some more graphic than others) that make this point more vivid.

But despite seeing these images, and taking stock of all of the potential harmful effects of exercise, the pros of exercise *far outweigh* the potential harms. You are much more likely to die from an inactive life than you are from an active one. Hence why we (ought to) exercise!

Secondly, we are not all equally well placed to exercise regularly. Some people work at jobs that are outside and involve physically demanding work (like being a brick layer). Others have jobs with very long hours that involve sitting in front of a computer for most of the day (like academics!). Some people live in congested cities where clean air itself is a scarce resource, while others live in beautiful countrysides with amble opportunities for hiking and biking. Some people have an education that better positions them to make long-term decisions about their health (e.g. to regularly exercise or not). Others have family situations that can make exercising more of a challenge (e.g. providing the primary care for a child or sick parent) than it is for others. And some enjoy a higher income that permits them to buy a gym membership that others could not afford.

Concerns about safety and equal access do not lead us to eschew the importance of exercise. No one declares: "Someone died riding a bike so let's ban all bikes!", or "Jimmy broke his leg playing soccer so let's ban soccer!". No one invokes the precautionary principle in the context of exercise. Perhaps we don't because we are all familiar with the risks of exercising and the risks of inactivity. We know the latter outweigh the former by far.

The point of this exercise it get to us to realize what the benchmark is, in terms of safety and access, for a measure of preventative medicine that we all would applaud. Once one makes vivid the realities of exercise, then, and only then, can one begin to form considered judgements about concerns of safety and equality for a health innovation that conferred even bigger health benefits-- like a pill that retards human aging by mimicking calorie restriction.

Many people hesitate or even refuse to take drugs that could promote their health because they fear any potential adverse side-effects. Yesterday I spent 45 minutes waiting in line for the H1N1 shot. And I overheard many conversations about the fears and concerns people had after reading the info sheet about the flu vaccine. But what these people fail to reliaze is that, unlike the flu shot, getting in their car to drive home, or riding a bike, doesn't come with a small print warning label. These activities are much more risky, but they only feel safer because you do not read a warning label each time you do them.

If everything in life had a warning label they we wouldn't fixate so much on the potential adverse consequences of pharmaceuticals rather than other potentially risky interventions-- like exercise. Because the latter is considered "natural" we tend to view it as inherently safe. But the fact that one intervention is "natural" and a second "unnatural" doesn't make one safe and the other risky. The data, rather than our intuitions, ought to guide rational decision-making about health innovations.