Tuesday, February 10, 2009

Rapa Nui meets Generation X, eh?

By chance, I recently read a commentary in Transfusion

and a book
that both featured Easter Island (Rapa Nui in Polynesian).What struck me as ironic was that Sayers uses the example of Rapa Nui to argue against the precautionary principle, while Wright uses the same event to argue for it.

Below is a tale that leads from an ecological disaster on a
Polynesian island to making a case against the precautionary principle to how not to alienate generation Xers on Facebook or My Space .... or, as I think about the saga,

  • Rapa Nui meets Generation X, eh?
-->(Musings on the pros & cons of loosening blood donor criteria to maintain supply) Background - Rapa Nui
In brief, Easter Island is an extreme example of deforestation and how it happened is open to debate. One theory, (and the one put forth by Wright in 2004) holds that Easter Islanders deforested the island
in the process of transporting and erecting their statues (aka moai), a situation made worse by rats eating palm seeds.

Accordingly, Wright postulates that there may have come a time when islanders chopped down the last tree knowing it was the last tree, but they were captive to worship of the moai, who represented their deified dead ancestors.

Since then research has shown that this hypothesis needs "tweaking" since University of Hawaii researchers have shown that the island was colonized much later than earlier thought:

In the Transfusion commentary, Sayers uses the Rapa Nui deforestation as a metaphor for the misfortunes that can happen if a limited resource such as the blood donor supply is mismanaged.

Sayers' main tenets [
my comments]:

Viewing blood shortages as due to inadequate recruitment (60% eligible but only 5% donate) is wrong because the true number of eligible donors is closer to 40% or less.

(Reference: Changing age distribution of the blood donor population in the United States)

[Even at 30 or 40% eligible, there's room for recruitment improvement.]

2. The idea that greater deferral equals greater safety is wrong. Sayers writes,
It was certainly important to emphasize that the principle had been overlooked when decisions were being made about reducing the risk of transfusion-transmitted acquired immunodeficiency disease. However, since then, many new justifications for temporary or permanent deferral reflect an inflexible application of the principle.
[Implication: The precautionary principle has outlived its usefulness.]

3. When the precautionary principle guides policy, “competing uncertainties” must be reconciled. i.e., when considering a new deferral, potential improvement in transfusion safety must be weighed against a further shrinking of the donor pool.

AND, if the deferral will result in a donor loss that threatens the supply, a "more flexible application of the precautionary principle" should be recommended.

[Flexible is undefined.]

AND, even if new eligibility criteria will have little effect on supply, taken together their cumulative effects could be significant.

[Implication: Even potential safety criteria with minimal effect on donor supply should be discouraged.]

Temporary deferral is a powerful disincentive for deferred donors, whose numbers are growing (now at 15-20%). Moreover, disgruntled deferred donors could spread the word via social networking.

AND, since civic disengagement is a characteristic of the newer generation of donors, we should not do anything that turns them off.

(Reference: Putnum RD. Bowling alone. The collapse and revival of American community. New York: Simon and Schuster; 2000)

[In other words, baby boomers (born between 1946-1964) and Generation Xers (born between 1965 and 1980) are less likely to respond to a civic duty to provide an adequate community blood supply - and if disenchanted - their anger can quickly spread via the Internet. ]

Interestingly, Sayers did not cite this 2003 Transfusion commentary, which extensively discusses Putnam's views.
5. A national workshop is needed to review donor restrictions, including deferrals, and reverse unnecessary ones.

Do not assume that compromised availability will be corrected by enhanced recruitment.

7. The UK has plans to reevaluate the relevance of some of the “more stringent” requirements for donor eligibility and their actions could be a model for others.(Reference: Shepherd A. The donor selection guidelines. Blood Matters. 2007 Summer;22:4-5)

Sayer also explains:

These comments could be regarded as capitulation to laxity in donor standards or resistance to the precautionary principle, but that is not their purpose. They are intended more to encourage acknowledgment that donor management must focus not only on the eligible, but also the deferred, the deferral process, and deferral outcomes.
The call to reexamine blood donor criteria is widespread. The issue is succinctly described by Elizabeth Caffrey in this 2007 editorial in the UK newsletter, Blood Matters:

Many of the blood donor selection criteria are specified in the EU Blood Directive and are now written into UK legislation in the Blood Safety and Quality Regulations (2005). These tend to be cautious both in respect of donors’ health and recipient safety.

This may have been laudable when there was an excess of volunteers, but in the current climate it is recognised that they need critical review and analysis as part of the wider blood safety versus sufficiency debate. The new legal status of these criteria adds further complexity to any proposals to relax them.
The issue is often framed as balancing safety against the practicalities of maintaining the supply. The arguments all skew in favour of loosening or abandoning the precautionary principle in favour increasing the donor supply or improving cost effectiveness

(See Dr. Strangeblood or How I learned to start worrying and hate the numbers).

Sayers' commentary has several weaknesses:

1. He emphasizes supply while ignoring demand. Specifically, he does not mention the possibility of a more rational use of blood components, decreasing transfusion using evidence-based principles for blood management.

It's like a war on drugs that firebombs the crops in Columbia, Afghanistan, etc., to decrease supply but does little about the demand for drugs within one's own borders. Dealing with supply alone is unlikely to succeed.

2. Nor does he allow for the rise of the "Millennial Generation" (born between 1981 and 2000), who are just entering the prime blood donation years, age 25-45, and who seem more socially engaged, as shown by Barack Obama's use of social network sites.

3. Sayers discusses social networking as having a potentially negative impact (deferred donors dissing blood centres), with no mention of the incredible power of sites such as Facebook and My Space to motivate donation.
For example:

Arguing for a loosening of the precautionary principle is widespread and seems justified if we assume that it has been applied indiscriminately and foolishly. No doubt many transfusion professionals believe this. They see a more flexible approach, whatever that is, as being a return to rationale decision making based on evidence-based principles.
In A Short History of Progress, Wright writes (Sorry, I could not resist the homonym):
The great advantage we have, our best chance for avoiding the fate of past societies, is that we know about those past societies. We can see how and why they went wrong. Homo sapiens has the information to know itself for what it is: an Ice Age hunter only half-evolved towards intelligence; clever but seldom wise....

Now is our last chance to get the future right.
Blood shortages are reported in the news weekly. The current economic crisis is likely to exacerbate shortages. As offices and plants close, the number of work-place donation sites will also decrease. Employers will be less likely to let employees take time off to donate. This has already been reported:
With all these pressures to loosen donor criteria, we still have a chance to use history to get it right.When Rapa Nui (as an analogy of how to mismanage a limited resource) meets Generation X and successive generations of blood donors, the message is surely to opt for blood safety over expediency, even in the face of uncertainty, providing there is a plausible risk as explained by the precautionary principle.

Isn't that the lesson of history?
  • At first there was no evidence that AIDS was transfusion-transmitted, although it was soon implicated.
  • Transfusion professionals in some countries denigrated non-A, non-B (HCV) surrogate tests as leading to a needless decrease in the blood supply.
  • Later some sneered at the idea that BSE could be transmitted by transfusion and called the risk theoretical at best.
  • Today some transfusion professionals ridicule the vCJD deferrals as being useless.
If we abandon the precautionary principle, won't it be deja vu all over again? Simply put, we don't know what we don't know.

Just for fun, see

  • O Rapa Nui E (which as a Canuck, I read as O Rapa Nui, eh?)
Millennial* values, involvement, and social capital
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