Monday, December 03, 2007

Saving Lives vs Extending Lives

Suppose there are two medical interventions (X and Y) we could provide to a population, but we cannot afford to provide both. So we have to decide which intervention should be the priority.

Intervention X would cure a portion of the population of a particular disease.

Intervention Y would not cure anyone of a particular disease, but it would extend the healthspan of the population by delaying the onset of age-related diseases and disability.

What might we be inclined to say about how important these interventions are. Which intervention should we fund, and why?

To determine what fairness requires in this kind of scenario we would need *much more information* than I have provided here. For example, we would need to know important details concerning the disease in question- like how prevalent the disease is (does it afflict 40% of the population, 0.01% of the population, etc.), how severe it is, how effective alternative treatments or preventative measures might be, etc. We would also have to know how significant the increase in healthy years would be with intervention Y. In other words, the information I provide in this simple case (i.e. X cures a disease, Y extends healthy life) is not sufficient for us to make a sensible judgment concerning priorities. And yet I believe many people will be inclined to do precisely this. Why?

Many people will be inclined to think there is an ethically significant difference between saving lives and extending lives. And thus this distinction is important to consider for it can have influence our attitudes concerning the priority to retard human aging.

No doubt many people will take the view that saving someone from cancer, diabetes or Alzheimer’s disease is so important we should label these laudable aspirations as a “requirement of justice”. And I would agree. However, many people who are willing to do this will also be very hesitant (indeed they might flatly reject) to extend the duties of justice to apply to the effort to retard human aging. And part of the reason for this, I believe, is that they believe we have a duty to *save lives* but not to *extend lives*. So let me explain why I think this distinction is mistaken and should be discarded.

However, before I reveal the folly of this distinction, let me try my best to give the most charitable reading of the insightful sensibilities that underlie the distinction. When we think of a life *saved* we often picture scenarios where someone rescues a baby from a burning building, or a young child is cured of an early onset disease. And in such cases it happens to be the case that the *magnitude* of the benefits conferred upon the recipient are potentially very large. Saving a young child’s life could result in conferring an extra 70 years of healthy living on said individual. And that is a very important benefit. It is important not only because it is 70 years of extra life, but because the recipient in this case is someone who, barring the intervention in question, would be considered among the “worst-off”. To die in the earliest stages of life is to suffer the most tragic of misfortunes. So the imperative to save lives captures both prioritarian sensibilities (the worse off someone is the greater the imperative to help them) as well as considerations of utility.

Consider further the role considerations of utility play in these cases, for doing so reveals how problematic the idea of “saving” a life really is. Suppose we provide a medical intervention to a two year-old child who would otherwise die. However, we know that this intervention will not eradicate the disease, it will merely delay the onset of the disease (and thus death) by 20 years. So when this child reaches that age of 22 they will die. Would we say that, in this kind of scenario, the medical intervention just extended the life of the patient or that it saves their life? What if the intervention would prove effective for 40 years, or 50 years, or 60 years? Or what if, taking things in the other direction, the intervention would only add an extra decade of healthy living, or just 5 years, or even only 1 year. When do we say the intervention saved the patient's life and when does it merely extend their life?

I suspect some of those who will feel committed to the saving/extending distinction are committed to some version of the sufficiency account of justice. That is, they believe that justice only requires us to bring people to some threshold of wellbeing and nothing more. And thus they might be willing to introduce some benchmark, perhaps the average life expectancy, and say that an intervention that brings a patient to that mark has saved their life rather than merely extended it. However, those above this benchmark (i.e. those already above the average life expectancy) cannot, by definition, have their lives *saved* in this sense. Medical interventions can only extend their lives. And extending people’s lives are not as important as saving their lives.

I argue, at fuller length, against this sufficitarian position in this paper here, so I wouldn’t elaborate on it further now. But it seems rather bizarre to say that, if you push a pedestrian away from an oncoming speeding car, thus diverting their demise, that whether you saved or merely extended their lives depends on their age. So if the pedestrian is your grandchild you saved a life. But if they are your grandparent you merely extended a life.

Intertwined with these various judgments are, I suspect, attitudes concerning the *quality of life* at stake. So part of the reason why people might be inclined to see extending life as less important than saving lives is that the latter also involves qualitative concerns. So saving a person’s live means the person in question will still have a number of healthy years they can expect to live. But when one talks about extending someone’s life they assume we are talking about extending the last stages of the life cycle, with its frailty and other disadvantages.

But the case for tackling aging is not about extending the last stages of a person’s life (i.e. keeping them in a frail stage for longer). It is about expanding a person’s health span. So extending a person’s live can mean adding disease-free years. Construed in this way, there is no difference (assuming all else is equal) between curing someone of a disease and extending their number of healthy years by retarding aging.

Now the story does get more complicated once we attempt to disentangle the utilitarian and prioritarian concerns that can arise here. If we drop (as I believe we should) the notion of saving people’s lives, and talk instead about extending lives, the utilitarian will place all of the emphasis on the magnitude of the benefits at issue. So an intervention that would extend a person’s healthspan by say 40 years should take priority over an intervention that would only extend a different person’s healthspan by 20 years. But what might the prioritarian say in this case?

For the prioritarian, the magnitude of the benefits themselves will not necessarily settle the issue (though they do matter and should not be ignored). This is so because what also matters is how advantaged or disadvantage the people in question are. So extending the healthspan of someone who can only expect to live to 30 can matter more than extending the healthspan of someone who is expected to live to 80, even if the intervention would confer a greater benefit (in terms of additional healthy years) on the more advantaged person.

So once couched in terms of a pluralistic prioritarian ethic, rather than a utilitarian ethic, one can invoke just the idea of extending people’s lives and do so in a way that accommodates some of the sensibilities of those who feel there is a moral difference between saving lives and extending lives. And once one combines these prioritarian sensibilities with an appreciation of the empirical complexities in this case, like the fact that the most prevalent diseases in the developed world are diseases of aging, talk of retarding aging begins to sound more fair and sensible. Indeed, I believe one can begin to make a persuasive case for describing such a duty as a *duty of justice*.