Human life is so precious, it seems crass to put a price on it. How can a pile of coins, paper or gold bars match a year on Earth? Life should be, quite literally, invaluable.

Yet that is the morbid question that health services, everywhere, inevitably have to ask. They have limited money to spend on sick and dying people, and whenever a new drug becomes available, they have to make a choice: will the few stolen months, or years, be worth the money it costs?

Our gut instincts may seem obvious: we should do all that we can to buy more time for the people we love. Yet Dominic Wilkinson, an intensive care doctor and ethicist at the University of Oxford’s Uehiro Centre for Practical Ethics recently wrote a thought-provoking article questioning these assumptions and asks us all to consider just how much we should be willing to pay for a longer life.

Intrigued, BBC Future phoned him to explore his argument, and to better understand the ways we currently calculate the price of life.

At the moment, drugs for terminal illnesses tend to be judged on two things – by how much they extend the lifespan, and the quality of life of the patient, using a scale known as the Quality Adjusted Life Year-saved (QALY). A drug that helps you live for an extra year, at half your general quality of life, would score about 0.5 years on this scale, for instance. “Alternatively, a drug that improved your quality of life for a year from a level of half normal, to full health would also score 0.5,” explains Wilkinson.

The UK recommends paying about £20,000 to £30,000 for each additional year of good health

From these calculations, a health service can then start to set a price on whether a drug is worth the cost. The UK’s recommendations, for example, are about £20,000 to £30,000 ($30,000 to $45,000) for each additional year of good health, once it has been adjusted to take into account the quality of life. So a drug that achieved 0.5 on the QALY measure would only merit £10,000-15,000 ($15,000 to $22,500). 

This inevitably means that some drugs have been rejected by the National Health Service (NHS), because they are simply too expensive: the breast cancer drug Kadycla, for instance, only extends the lifespan by about six months for a cost of £95,000. Even if the quality of life during those few months is equal to that of a healthy person, it still hugely overstretches the limit. (Other healthcare providers may have different criteria, of course – but they all have to weigh up the costs and benefits in some way, before offering to fund a treatment.)

Campaigners argue that the pharmaceutical companies should lower the costs of such treatments, and that health services should also invest more and more money in drugs that will buy terminally ill patients some more precious time. Given these strong and emotive arguments, the UK recently considered increasing the threshold for terminal illnesses – to as much as £80,000 ($120,000) for each “quality-adjusted year saved”.

As doctors looking after patients, we are ethically driven to say that ‘I know it is expensive but my first duty is to help my patient – Dominic Wilkinson

Wilkinson says this attitude is completely understandable – and it’s often the doctors, as well as the patients themselves, who argue the case. “As doctors looking after patients, we are ethically driven to advocate for patients, to say that ‘I know it is expensive but my first duty is to help my patient,’” he says.

But the inevitable sacrifice is that this money will be taken away from other areas of care, such as mental health services or help for people with disabilities – measures that may be crucial for improving the quality of life for people at the start or middle of their lives.

Is it worth forfeiting one person’s comfort to buy another a few more months at the end of their life? When making these decisions, it’s important to gauge public opinion. And although you might assume that most people would pay infinite sums to buy a few extra years, recent research suggests we do not all place such a high value on the sheer length of the lifespan.

Wilkinson points to a detailed UK study of 4,000 people that clearly explained the different ways the health service’s limited resources could be spent, and asked the participants for their preferences.  “They clearly indicated that they weren’t comfortable with giving more money to people who were terminally ill, compared with people who might benefit at other stages of their lives.”

Perhaps most surprising were the results from a study in Singapore, which questioned elderly, but otherwise healthy, citizens as well as those suffering from terminal cancer. “The striking thing from that is that they were prepared to pay an awful lot more money for palliative care so they could be treated in their own home, than drugs that would extend life,” says Wilkinson.

Many participants would pay just £5,000 to extend life by a year

On average, the participants would pay £5,000 ($7,500) for a treatment to extend life by a year. But they were willing to pay about twice that amount – £10,000 ($15,000) – on better palliative care, such as better nursing that would allow them to die in the relative comfort of their homes, rather than a hospital. “It seemed to provide a fresh way of thinking about difficult decisions.”

Clearly, these studies are not the final answer; it is hard to know if these opinions are shared among different people in different cultures and facing different illnesses; there are also questions about just how effectively a calculation like the QALY scale can really, objectively assess a treatment’s potential. But Wilkinson thinks that we should at least consider these different opinions before devoting more and more money to extending lifespans.

“Although it’s very understandable to want to buy more expensive drugs for the terminally ill, I don’t think it reflects the view of the general public or those of the patients,” he says. “Nor is it clearly the right ethical approach.”

As the population ages, and healthcare grows ever more advanced, and expensive, these issues will only become more pressing. The eminent American surgeon Atul Guwande has long questioned whether it is better to stretch out the lifespan, instead of increasing the comfort of our available years. Ezekiel Emanuel, the former director of the Clinical Bioethics Department at the US National Institutes of Health, has even claimed that he would refuse all life-extending healthcare at the age of 75, rather than entering a cycle of ever more intense treatments to draw out his last few years.

Few of us may decide to take such a drastic decision, but anyone, at any age, may do well to consider the value of their time on Earth and what we are doing to make the most of it.

David Robson is BBC Future’s feature writer. He is @d_a_robson on twitter.

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