Thursday, July 7, 2011

Is Donating Bone Marrow A Charitable Act?

A few weeks ago, the Australian Bone Marrow Donor Registry contacted and informed me that I have matched with a person who may require a bone marrow transplantation. I told them that I was interested and went in last week for some confirmatory testing. An interesting thing that I have noticed is that a significant number of people who I have told about this have responded with “that is so generous; I could never do that”. This is the idea that I wish to explore. I’d like to begin with an apparently unrelated hypothetical:
A man is out for a late night walk down a country road and he notices a car stopped on the side of the road with its hazard lights on. Upon investigation, he finds a woman breathing heavily and clutching her chest. She tells him she believes she is having a heart attack. Unfortunately, neither of them have a mobile phone on them. She asks him to use her car to drive her to the hospital, as she is in too much pain to do so. The man does have a license. After a few seconds, the man says that he rather not, as the potential risk of crashing the car is too high.
While I cannot say for certain, I think most people would find the justification for not offering help to be quite weak; no one sees driving a car as being too risky as to not offer help to someone who may die without it. To get an idea of the risk associated with driving a car, the world death rate for motor vehicle accidents is 20.8 per 100,000 people (from the Wikipedia page, which quotes WHO statistics).

The point of this hypothetical is to highlight a contradiction in with the way that the people who I spoke of at the beginning think about bone marrow donation. Statistically speaking, donating bone marrow is safer than driving a car. For clarification, there are two procedures used to harvest bone marrow. The first and most common is a peripheral bone marrow harvest’; this is where the donor is given a drug to stimulate their blood marrow to grow and then they give blood and the bone marrow cells are harvested (in the same way as white blood cells are harvested for donation). As such, the risk associated with donating bone marrow by this method has the similar risk to donating blood; that is, a negligible risk. When most people think of a bone marrow donation, they think of extraction from the hip bone. This requires a general anaesthetic in most cases and it is this that presents the only risk of death (in that, no deaths have ever been recorded due to the actual extraction process). However, using even the most conservative figures (i.e. the ones that show the highest mortality rate), the death rate for general anaesthesia is around 14 per 100,000 people (from this study).

So, statistically speaking, it would be safer to give bone marrow to someone that to drive them to the hospital. However, I do not think that the people that I spoke of would change their view of not wanting to donate bone marrow because of this (I specifically did express this point to one of them and they did indeed not change their view). I am not entirely sure why. I see only minor differences in the scenarios and nothing to make them categorically different (well, as far as I can tell). So I throw it open to my highly intelligent audience; is there anything that would make not donating bone marrow more justifiable than not driving someone to a hospital?

[One potential criticism I could see is that I have used the world data motor vehicle accident death rates and, as such, will be much higher than any given country (for example,  the death rate in Australia is around 5 per 100,000; much lower than the world figure). However, the same is true of general anaesthesia figure; the study used data from any published study (excluding only those that were not in English). As such, it would probably be much lower in any given first world country (as is the case with the death rate from motor vehicle accidents).]