The same limitations apply in microcosm in some areas of medicine; those such as cardio-vascular disease (CVD), for instance, where the relationship between high LDL and CVD appears to be too complex to form a basis for sound policy. Unfortunately, once a hypothesis is widely accepted, it becomes difficult to dislodge. Dr Malcolm Kendrick writes:
If your hypothesis is that a raised LDL causes CVD, then finding someone with extremely high LDL, and no CVD, refutes your hypothesis. Unfortunately, but predictably, the authors of the paper have not questioned the LDL approach. Instead, they fully accept that LDL does cause CVD. So, this man must represent ‘a paradox’. They have phrased it thus:
Further efforts are underway to interrogate why our patient has escaped the damaging consequences of familial hypercholesterolemia [FM] and could inform future efforts in drug discovery and therapy development.’
To rephrase their statement. We know that high LDL causes CVD. This man has extremely high LDL, with no CVD, so something must be protecting him. I have an alternative, and much simpler explanation: LDL does not cause CVD. My explanation has the advantage that it fits the facts of this case perfectly, with no need to start looking for any alternative explanation. Very high LDL and no cardiovascular disease – at all!, Dr Malcolm Kendrick, 12 MayDr Kendrick goes on to to cite the longest and one of the world's largest studies of people diagnosed with familial hypercholesterolaemia (FH). Contrary to current popular thinking it shows that 'people with FH have a lower than expected overall mortality rate – in comparison to the ‘normal’ population. Or, to put this another way. If you have FH, you live longer than the average person.'
This to me means that government policymakers should be more humble: when it comes to complex problems outside their expertise, they should admit to themselves that they don't know the best solutions. That doesn't mean they should do nothing: government can, and should, identify our social problems and raise the revenue to help solve them. It can actually do those quite well. But when it comes to solving our complex problems, it should consider issuing Social Policy Bonds, which do not presuppose how our problems shall be solved, nor who is best placed to solve them.
For more about Social Policy Bonds see here. For application of the Social Policy Bond principle to health, see here.