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Obesity and gastric bypass: putting a value on medical treatment

The UKs National Institute of Health and Care Excellence has a basic remit of evaluating the costs and benefits of medical treatment. Last week, it emerged that NICE will change its guidelines so that more people with Type 2 diabetes will have access to gastric bypass surgery. I think it is fair to say that the reaction to this news was not particularly positive. So, has NICE got its sums wrong?
       Evaluating the costs and benefits of medical treatment is always going to be a controversial and thankless task. Just about any decision is likely to upset someone. For instance, telling a cancer patient that her treatment is not 'cost effective' is clearly not going to be popular. But, from the other side, saying that gastric bypass surgery is 'cost effective' did not go down well with taxpayers. So, keeping everyone happy is impossible. That does not mean, however, there are not right and wrong ways to measure costs and benefits. And, there seems to be an increasing swell of opinion that NICE is not doing things right. 
      At the moment NICE bases its decisions on private costs and benefits. So, when assessing whether it is cost effective to treat a person with type 2 diabetes they focus solely on that person. With this mind-set it is easy to see why the gastric bypass is cost effective: the surgery costs relatively little, has a high success rate, and lessens the need for subsequent treatment. And, it is equally easy to see why a cancer treatment may not be cost effective: the drugs are expensive, have a lower success rate, and only postpone the need for further treatment.
      But, is it enough to only focus on private costs and benefits? What about social costs and benefits? To illustrate the point with a somewhat provocative example, compare two 40 year old women with cancer. Jane has no family, no job and is living on welfare benefits. Sarah has three young children and a high paying job. Currently NICE treats Jane and Sarah as identical. Once we take into account social costs and benefits it is a no-brainer that treating Sarah is more cost effective than treating Jane. The social benefits include three happy children and the future tax revenue. 
       NICE and policy makers currently seem to shy away from measuring such social benefits on the basis it all gets a bit too judgmental and controversial. But, that seems too much like wishing a problem would go away. And, the gastric bypass debate illustrates that social benefits and costs are not just about kids and tax receipts. In particular, we have the social costs of moral hazard and fairness. 
 
Moral hazard. The new guidelines will increase the perception (rightly or wrongly) that its ok to live an unhealthy lifestyle; whatever happens, the medical profession will save you. The effect of this will surely be to increase the number of people living unhealthy lifestyles and consequently increase the number of people with Type 2 diabetes. To put things explicitly in the language of social benefits and costs we have something like: treating Fred today makes it more likely that Jack will need treatment in the future.   
 
Fairness. Given that one of the main causes of Type 2 diabetes is lifestyle many people (not all) get Type 2 diabetes because of choices they consciously made. Should they be 'rewarded' for that? Fairness norms typically take account of intentions as well as outcomes. On that basis, someone would be seen as 'less deserving' of treatment if they partly bring about their own problems. So, society might be happier if the money was spent on, say, breast cancer than on people who have Type 2 diabetes because of lifestyle.

Relating cause and consequence in health outcomes is difficult. As is measuring the consequences of moral hazard. Again, however, to dismiss such things as too difficult to take account of seems like wishing a problem away. I think, therefore, the role played by social costs and benefits in health care needs a lot more thought and recognition.    

 

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