This piece was originally written in 2006. Although Ariel Sharon’s massive stroke figures in the beginning, this was really just the instigator for a broader piece on consent.

The headlines were suitably dramatic. The Globe’s was ‘With victory in his grasp, fate intervenes.’ The Times of London: ‘First stroke treatment could have triggered the second.’

Only time can tell but it is extremely unlikely that Mr Sharon will return to political life. Mr Sharon’s condition highlights the uncertainties of life. While many of us think of medicine in absolutes, medical therapeutics remains a matter of probabilities. Mr Sharon’s illness is hardly unique. Many Canadians suffer from similar conditions that predispose to strokes. The treatment, particularly if a person has already suffered from a stroke, is precisely the treatment that Mr Sharon received.

Doctor – “Sir, you have an irregular heart rhythm that can cause your blood to clot. If one of those clots, God forbid, travels to your brain, you could have a stroke.”

Patient – “Oh, that can’t be good. Is this treatable?”

Doctor – “Well, we can’t completely prevent strokes, but we can reduce the chance of having one. The choices are an aspirin a day or blood thinners.”

Patient  – “What’s the better choice?”

Doctor – “Well, if we take a 100 people like you, 6 are likely to have a stroke in the course of the year – so the risk is 6%. If you take aspirin, you can reduce that risk from 6% to about 4%. If you take blood thinners, you can reduce the risk to 2% or even less.”

Patient – “What are the risks of taking aspirin compared to blood thinners?”

Doctor – “The risks of taking an aspirin a day are mostly around gastrointestinal bleeding. In most people, we can detect and treat that well, but in a minority of patients, it can be life threatening. The risks of taking blood thinners are also very uncommon but can be quite serious. If you are prone to falling, for example, and you bang your head hard, you can have a bleed in your head. If you are unlucky enough to have a second stroke while on blood thinners, the stroke could become a bleed.”

Patient – “Is that serious?”

Doctor – “It can be. Mind you, it’s exceedingly rare, likely no more than 5 people in a 1000 who are on blood thinners suffer from a major head bleed.”

Patient – “Well, doctor, what would you do?”

Discussions like this take place because of a principle called Informed Consent enshrined in Canadian law and our current ethical framework: Patients must be informed of the risks, benefits and alternatives of a proposed treatment before consenting to it. This principle was enshrined by a decision of nothing less than the Supreme Court of Canada.

This is easy enough when the choices are straightforward. Inevitably, as our treatments become more complex, the risk-benefit evaluations also become more complex. In the example above, the risk of stroke is somewhat high – 6% per year, rising to 12% per year if a person has already had one stroke. The risk of a bleed is less than a tenth of that. It’s not usually a difficult decision, although it occasionally becomes one after high profile cases like Mr Sharon’s.

Other situations are more difficult to explain to patients. Suppose you have a disease that kills half of those who are afflicted with it within 5 years. Surgery can cure the disease but the risk of dying from surgery is 20%. Do you go for the 50% chance of outliving your disease or the 20% risk of dying from the attempt at treatment? If you’re 40 years old, you may feel like taking the surgical risk, but what if you are 75 years old? What if the risk of dying during surgery is low, but there is a high risk of having a disabling stroke or kidney failure that requires dialysis?

When presented with scenarios like this, many patients ask the physician to effectively make a decision. Which begs the question of why we go through this process at all.

How can we expect people to make truly informed decision when the information presented is a matter of probabilities? And if it boils down to the physicians’ recommendation, why go through the anxiety-provoking litany of risks and alternatives?

But maybe that’s the whole point. As physicians, we are not here to spare patients the anxiety of their health care choices. We are here to allow them the anxiety of making uncertain decisions based on their values and their judgement. Just as your banker wouldn’t tell you what to do with your money without explaining the risks and benefits, neither should your physician tell you what to do with your health without an explanation of the same.

Mr Sharon’s condition serves to remind us, in the most dramatic way possible, that there are no guarantees in life.

[Update 1: It turns out your bankers don’t tell you the risks and benefits of what they are recommending you do with your money. This piece was written before the collapse of 2008. Maybe a little more informed consent in the financial markets would have been a good thing.]

[Update 2: Almost six years later, Ariel Sharon remains comatose but has been moved to his ranch starting in late 2010].