Thursday, October 08, 2009

Statins and Health Inequalities: Some Thoughts

Last week I read this article on statins and health disparities which provoked a few different thoughts which I wanted to note here, especially as they pertain to similar concerns that arise with respect to aging interventions and debates in biogerontology.

Before addressing the article let me say a bit about "egalitarianism". My understanding of the term "egalitarian", at least as that term is commonly utilized in contemporary debates in political philosophy, is that it is a term attributed to one who believes that distributional equality of some good or goods (like wealth or health) has considerable moral value in itself (and, conversely, that (unchosen) inequality is unjust).

As I have noted before, I myself am not an egalitarian. When it comes to the issue of how much weight to attribute to equality, the devil is really in the detail (not the abstract concept!). Much depends on the good in question, the level of disparity, and the causes of the inequality and the different challenges that often impede the realization of a more equal (or rather optimal) situation.

I take a diachronic, rather than synchronic, view of justice. Telling me that inequality X is present at time 1 tells me little (if anything) about the justness of a situation. But for those inclined to adopt a synrchonic view of justice, one that is premised on our abstract intuitions concerning what is fair, hearing that an inequality exists is all they need to hear before they are inclined to demand that we mitigate such inequalities (even possibly by levelling down, depending on how strict of an egalitarian one is).

Even though I am not an egalitarian, I am interested in learning why so many (at least academics) hold such a view and what follows from their position. In this earlier post, for example, I argued that if one is an egalitarian of the kind Cohen defends then one ought to take seriously the issue of how inclusive your choice of partner is (which I actually think is a tenable conclusion, but not by appeal to egalitarian concerns).

And in this post I brought attention to the fact that the infant health inequality among the rich and poor has narrowed. To an egalitarian, the information that the gap between the neonatal and infant mortality of rich and poor infants has narrowed might be cause for celebration. Less inequality is inherently good. However, once one notes the reason why this is so-- namely, that part of the reduction in infant health inequality is due to the fact that children of highly educated parents now have an increased risk of complications and death because mothers are more likely to utilise fertility treatments, and hence have a higher change of multiple births-- the intuition "less inequality is good" looks perverse. When it comes to health, "leveling down" is not the goal. What we really want is to bring everyone up. So prioritarianism, or sufficiency, probably underpins most the sensibilities of those who claim to be egalitarian.

This brings me to the article on statins and health inequalities. My interest in this article stems from my interest in the egalitarian objection to aging interventions. Many critics dismiss the prospect of an aging intervention because such a medical intervention, when it arrives (and I think it is really a question of when, not if) will not (at least immediately) be available to all people on the planet. And from this they form the judgement that, "all-things-considered", such a technology will exacerbate injustice and do more harm than good. And thus these kinds of sentiments impede the development of biogerontology, perhaps this century's most important science.

But such a judgement is very naive and misguided. In fact, one can only arrive at such a judgement if one develops a judgement of what justice requires "only-one-thing-considered"-- and that one thing is what weight ought we to place on the abstract value of equality? But if we insist on subjecting our moral sensibilities to a determination of what justice requires "many-things-considered"-- then we will not eschew medical innovations that might have some adverse (at least) short-term impact on relational considerations but, in absolute terms (and in the long run), will improve the situation of all.

It is important to recognise that health is not a zero-sum game- that is, a game where the total amount of health available is fixed and redistributed, so that extra health for X comes at the price of less health for Y. Of course in some cases, like rationing scarce medical resources, things are like this. Either we fund treatment for disease A or for disease B. But we should not generalize from these cases to health in general.

Health itself is not a zero-sum game. If you achieve more health via exercise and diet that benefit does not come at the cost of someone else who thus suffers more disease and an earlier death. Your remaining healthy for longer need not reduce the amount of health available to me. Indeed, by remaining healthy and productive you can increase the likelihood that health dividends will also come my way by helping to reduce the strains on medical resources that are scarce and need to be rationed.

This brings us then to the study on statins. Statins are cholesterol lowering drugs that can reduce the risk of cardiovascular disease. But statins are not freely available. And thus those who can afford them enjoy a reduced risk of heart disease. A sample from the paper:

As an innovation, statins have a number of attributes favoring effective diffusion and adoption. Classical diffusion theory considers the following factors: “relative advantage” (e.g., effectiveness relative to alternatives), lack of “complexity” (e.g., simplicity of use), “compatibility” (fit with existing values and practices), “observability” (outcomes can be observed), and “trialability” (users can experiment on a limited basis) (Rogers 2003). Statins possess, to some degree, all of these attributes, and each can be considered from the standpoint of both physician and patient as the adopter. Empirical data suggest that the diffusion of statins has indeed been rapid.

....Statins are far more powerful than prior cholesterol-lowering drugs and, of particular importance, are highly effective in lowering low density lipoprotein (LDL), the fraction of total cholesterol that is most closely associated with heart disease and the principal target of treatment guidelines (NCEP 2002). Statins can achieve reductions of up to 50 percent or more in LDL (Jones et al. 1998), but they are expensive. Simvastatin (brand name “Zocor”) is one of the most effective and frequently prescribed statins, and its cost was over $120 a month in 2003 for a starting dose of 20 milligrams per day (The Medical Letter 2003). In addition to being costly, statin use requires access to lab services and physicians who prioritize prevention, adhering to guidelines for cholesterol screening and treatment. It also requires resources such as patient willingness and ability to fast overnight and present for a scheduled blood draw. Blood analysis is essential for diagnosis, drug titration, and monitoring side effects.

....While the more advantaged were once more likely to have high levels of cholesterol and LDL, they are now definitively less likely. Additionally, exploratory analyses suggest that income is positively associated with statin use accounting for clinical need. While statins hold great promise for improving cardiovascular health, it appears that they may have contributed to expanding social disparities in cardiovascular risk.

....The influence of technologies on socioeconomic disparities is subject to two important modifiers: (1) the nature of the technological change and (2) the extent of its diffusion and adoption. While resources affect access to technologies, some technologies can also affect resources, lessening the productivity of various health inputs. In our case, statins could have helped to equalize cholesterol levels by overtaking the value of lifestyle inputs. Significant disparities in diffusion and adoption, however, resulted in a net effect of gradients favoring the wealthy. It is important to note that average cholesterol levels declined during this period at all income levels. Hence, statins have contributed to an overall improvement, yielding absolute health benefits at all incomes. Health enhancing innovations, however, are typically implemented in a context of inequalities, and an innovation that raises average health can nevertheless create new links between social factors and disease pathways.

So what to make of this? Well, if what one really wants to argue is that everyone, and not just the rich, should have access to statins, then we should invoke a prioritarian or sufficiency or even utilitarian framework. An egalitarian framework distracts us from the real concern (i.e. access to statins) and often leads people to endorse the conclusion "then none should have access to X". There is much more to be said here. But I will leave things there as this is a complex issue which requires more reflection that I can offer here at the moment. But I want to leave things with this final thought:

I believe the prevalence of egalitarian intuitions helps explain (at least in part) the dominance of the "disease model" approach to the medical sciences. People eschew aging research and positive psychology because they believe it is inappropriate to worry about improving the health and happiness of those they consider "the advantaged", when there are those who suffer early onset disease and mental illness. But we should reject this simple dichotomy and its conclusion that we should only use science to help those with the worst afflictions.

To overcome the exclusive vision of the medical sciences (namely, that medicine should only aid those who are sick and ill) we need to overcome these misplaced moral sensibilities. Fairness is much more complex than invoking simple egalitarian intuitions.