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The writer is a scientific commentator.
On Friday, the UK parliament will vote on whether terminally ill people with mental capacity can seek medical help to hasten death. If the assisted dying bill is passed, the country will move closer to sanctioning state-assisted suicide, bringing it in line with countries such as Switzerland, Belgium and Canada.
There are compelling arguments about both sides of this emotional issue and the result seems impossible to predict. While public opinion broadly supports the change, parliamentarians seem more divided.
But one aspect has been overlooked: the science of predicting survival. As a safeguard, the bill restricts the right to assisted dying to those who have less than six months to live. While rough survival estimates can be calculated using groups of patients, prognoses for individuals are more difficult to pin down.
“My research shows that there is no reliable way to identify patients who have less than six or twelve months to live. . . at least, no method that is reliable enough to act as some kind of ‘safeguard’ for the proposed legislation on assisted dying,” Paddy Stone, professor emeritus and former head of the Marie Curie palliative care research department at the University College London. this week.
According to Nicola White, senior researcher at the same unit, health professionals are no more able to offer accurate survival timelines today than they were 30 years ago, even with the help of additional markers such as blood tests. While predicting survival for cancer patients is difficult enough, it is even more so for heart failure and neurodegenerative diseases. These important challenges – accurately predicting an individual’s survival and deciding what qualifies as a terminal illness – have been overshadowed by other issues, such as the role judges will play.
Predicting survival is like forecasting the weather: the closer a patient gets to the end of their life, especially in the last 24 hours, the easier it is to estimate the prognosis. Predicting the last seven days of life is more difficult than the last 24 hours; Beyond that, things become even more unstable.
To check accuracy, studies sometimes ask doctors to say whether a patient nearing the end of life has “days,” “weeks,” or “months” left. A 2023 paper covering about 98,000 patients showed that doctors were 74 percent accurate in judging who would live less than 14 days and 83 percent accurate in judging who would survive more than a year. But that figure fell to 32 percent when those in the middle are estimated to likely live “weeks” or “months.”
“All studies from this country and others show that estimating [whether a patient has] “Six months to live is extremely difficult and not very accurate,” says Irene Higginson, professor of policy and palliative care at King’s College London and scientific director of the charity Cicely Saunders International. “The science is not that well developed and I’m not sure it can be, because individuals vary so much.” Higginson declined to offer his opinion on the bill.
Many palliative care professionals fear that assisted dying will drain resources from end-of-life care. Last month, the Palliative Medicine Association expressed its opposition due to concerns about protecting the vulnerable; inadequate provision of end-of-life care services across the UK; and the impact on trust between doctor and patient. Higginson points out that palliative care already includes the right of patients to refuse medical treatment.
Opponents point to other countries as evidence of a slippery slope: Belgium and the Netherlands now allow euthanasia for those under 18; In Canada, lonely and homeless people have asked to die. A psychiatrist at the University of Toronto described the country’s “medical assistance in dying” legislation as a “bait and switch”with a well-intentioned law that “metastasizes” into something malignant.
Those who defend assisted dying have good intentions. They cite patient autonomy and human rights. They maintain that a good death should not be limited to those who can afford a trip to Dignitas.
The goal of this column, however, is not to argue for or against the assisted dying bill, but to ask whether the science behind a safeguard meets what is asked of it. The answer? Possibly not. Ultimately, parliamentarians may regard scientific uncertainty in predicting survival, among other difficulties, as an insignificant consideration when compared to the opportunity for liberalizing reform and patient choice.
And that’s really the point: this deeply important vote must be informed.