Category: Medicine

Suicide and multiple equilibria

I don’t aim to be the cynical economist that Tyler writes “might suggest social stigma for suicide, rather than forgiveness” but it is frightening how easy it seems to be to jump to the sad equilibrium. The story of suicide among young boys in Micronesia (I recommend Malcolm Gladwell’s The Tipping Point for a discussion but will cite some online material) illustrates how actions and social attitudes reinforce one another. As the action becomes more common, perhaps reaching a “tipping point”, condemnation declines, and the action increases even further. Here, from one of the researchers who first documented the story, is a chilling description of suicide in Micronesia:

As suicide has gained familiarity among youth, the act itself has become increasingly more acceptable or even expected. Suicides appear to acquire a sort of contagious power. One suicide might serve as the model for successive suicides among friends of the first victim. There has been an apparent increase in suicides among very young children, aged 10-14. Evidently the idea of suicide has become increasingly commonplace and compelling, and young children are now acquiring this idea at earlier ages.

Another of the earlier researchers writes:

Love songs mention suicide, youths discuss the subject openly among themselves and at times make suicide pacts with one another, and youngsters express admiration of those who have taken their own lives and are mourned so terribly by their families and friends. What is even more shocking, however, is that a number of adults in our communities seem to share the belief that these young people have died altruistic and even heroic deaths. If the majority of Micronesians really believe that suicide is an honorable option, then this paper is thoroughly useless and all of us had better resign ourselves to continuing high rates of suicide in the future. Young people, after all, are very quick in sensing the basic values of their elders. If they get the impression that we ourselves honor suicide, then they will be only too happy to oblige by hanging themselves.

Note that one could tell similar stories in the United States about divorce, having children out of wedlock, welfare dependence etc. (also teenage suicide at a local level).

Here is a graph of suicide rates in Micronesia indicating a massive increase in a few short years in the early 1970s. The tipping theory generates credence when we note that virtually all the suicides take a similar, ritualistic form involving hanging.
suicide.bmp

Dalkon Shield, Silicone Breast Implants, Fen-Phen

A bill to move class action lawsuits out of the state courts and into federal courts narrowly failed in the Senate. Senator Tom Daaschle, explained his opposition to the bill this way, “It is the Dalkon shield, it is silicone breast implants, it is fen/phen.”

Good list. Wrong conclusion. The A.H. Robins Co. was driven into bankruptcy and forced to pay 3 billion dollars in damages but the Dalkon shield has been shown to be effective and safe. Silicone breast implants have been reviewed in studies by the AMA, the Institute of Medicine, the Canadians, the French, the British and others. All conclude that there are no unusual problems with the implants (any surgery has risks of course). The FDA will probably soon allow the implants back onto the market but in the meantime Dow-Corning has been driven into bankruptcy and tens of millions of dollars have been spent on lawsuits. Fen/Phen does looks like a serious health risk but tort law had nothing to do with removing the product from the marketplace. (Moreover, the issue is complicated. Only the Fen in Fen/Phen looks dangerous and that was approved in 1973).

We should spend More on Health Care

Tyler appears to be growing more skeptical of the value of health care spending (see his posts here and here). A simple model explains most of what is going on and why he and another of my very smart colleagues Robin Hanson, are wrong. In the graph below spending on health care is on the X axis, health outcomes are on the Y axis. Spending shows diminishing returns. We are currently at point Q on the graph labeled T1 – note that at this point marginal increases in spending have little effect on output (Tyler asks, What margin has low value? Answer: The marginal dollar). Even fairly large increases or decreases in spending will not change outcomes very much given that we are currently at point Q.

Why are we spending so much as to push us into the flat portion of the production function? One reason is that out-of-pocket expenses for medical care are much lower than true costs – we typically are spending someone else’s money. A second reason is that the marginal utility of wealth is low if you are dead so spending on health care near the end of life has unusually low opportunity cost. A third reason may be that various psychological factors make the desire to avoid regret particulary strong for health care, as Tyler speculated earlier.

Although the marginal dollar has low return the value of improvements in medical technology is enormous. These gains are illustrated by the shift from T1 to T2. It has been estimated, for example, that increases in life expectancy from reductions in mortality due to cardiovascular disease over 1970-1990 has been worth over $30 trillion dollars – yes, 30 trillion dollars (for this research see: book, papers, summary). A conservative estimate is that 1/3rd of these improvements in life expectancy were due to better medical technology. One third of the annual benefits is $500 billion – this is much more than total government spending on medical research (the budget of the entire NIH is around 25 billion).

The low value of medical spending at a particular point in time and the high value of medical research over time suggest that we would be much better off if we cut back on medical care spending and devoted the funds to medical research. We should spend less on Medicaid, Medicare, Prescription drug plans etc. and use the savings to better fund the NIH (or other methods of increasing medical research such as prizes etc.)

HealthModel.JPG

Notes on Genetic Insurance

My idea of genetic insurance created some controversy with Randall Parker at FuturePundit, Brock Sides at Signifying Nothing, and MR’s guest blogger Lloyd Cohen raising some objections. One of the objections that all three had in common (dealt with in my papers but not in the post) is that adverse selection is still a problem if people lie about having taken a test. This minor problem is easily handled, however. Insurance companies could have a clause in the contract forbidding previous tests. We don’t worry so much about people having a theft and then buying home insurance and the issue here is quite similar. (See my papers for a little more on this issue).

Randall at FuturePundit, however, raises a more serious problem. As the price of genetic tests falls it will soon be economic to sequence a person’s entire genome at birth or even before (see Randall’s posts for some links on costs). In this case, genetic insurance works only if the parents buy the insurance. This is not so implausible (especially not for those who have their child’s DNA sequenced!) but it is a real issue. (We should also remember that genetic insurance will be quite cheap because most people do not have serious genetic defects.) If we have genetic insurance today, however, we can perhaps avoid the adverse selection problem for a couple of decades and that may be good enough for one of two things to happen 1) genetic engineering will reduce the need for insurance (sequencing is much more valuable if there is genetic engineering to correct defects) or 2) genetic insurance could evolve into a more Rawlsian scheme (perhaps involving government at some level) in which payments are made at birth to compensate for Nature’s genetic lottery.

The case for health care spending

In a previous post I wondered whether additional spending on health care in fact brought greater health. Whether we do controlled experiments, or look at cross-national data, a convincing effect is often hard to find.

Brendan Kennelly of Lehigh referred me to this OECD paper, which examines cross-national data to find a positive health effect from health care spending. The result is much stronger for women than for men.

I asked Robin Hanson what he thought of the piece, here is his response:

When a coefficient is truly zero, about 5% of the studies estimating that
coefficient should show a significant difference at the 5% level. And if
people search for specifications that will give this result because they
believe the coefficient is not zero, you might expect 10-20% (or more) of
the reported results will show a significant non-zero coefficient. So
given the current state of econometric practice, the most you could
reasonably hope for when a coefficient is really zero is for about 90% of
the studies to fail to find a significant effect of the desired sign. This
is the current state of the evidence on the aggregate effects of medicine
on health.

My take: The whole debate still makes may head spin. I wonder how much of health care expenditure is geared toward alleviating anxiety (“we did all we could…”) rather than improving health per se. We may be mismeasuring the relevant output. If we could measure the total costs of illness, what percentage of the total would come in the form of anxiety? Furthermore, health care is not a single thing. The marginal return from some forms of health care (bypass operations?) is certainly high, in other cases the return much lower or perhaps negative. So perhaps the debate should shift away from aggregates, and toward trying to identify which health care expenditures we can do without, or do not need to subsidize at current margins.

The wonders of money

…lifting children out of poverty can diminish some psychiatric symptoms…A study published in last week’s issue of The Journal of the American Medical Association looked at children before and after their families rose above the poverty level. Rates of deviant and aggressive behaviors, the study noted, declined as incomes rose.

“This comes closer to pointing to a causal relationship than we can usually get,” said Dr. E. Jane Costello, a psychiatric epidemiologist at Duke who was the lead author.

The study tracked 1420 children, many of whom lived on an Indian reservation. A local casino opening lifted many out of poverty, and also improved their mental health:

…the rate of psychiatric symptoms among the children who had risen from poverty was dropping. As time went on, the children were less inclined to stubbornness, temper tantrums, stealing, bullying and vandalism – all symptoms of conduct and oppositional defiant disorders.

After four years, the rate of such behaviors had dropped to the same levels found among children whose families had never been poor. Children whose families broke the poverty threshold had a 40 percent decrease in behavioral symptoms. But the payments had no effect on children whose families had been unable to rise from poverty or on the children whose families had not been poor to begin with.

Even I, author of a book called In Praise of Commercial Culture (see to the right), am surprised by this result. Supposedly the wealthier parents were now able to spend more time with their children, thus improving their mental health. I wonder whether the key factor instead might have been improved behavior on the part of the parents.

Here is the abstract, plus you can buy a copy of the original research for $12.

Addendum: David Levy, citing Adam Smith, wonders if it isn’t the growth rate of income that makes people better off, rather than the level.

The doctor drain from Canada

Unlike most libertarian-oriented economists, I find persuasive the left-wing arguments that individuals have a positive right to medical care. The problem is, most governmental systems are proving unsustainable in the long run. They are affordable only by rationing, which frustrates doctors and patients alike. The Canadian system is (barely) tolerable, only because so many Canadians come to this country for their care.

Read this article from The New York Times.

Here is one money quote:

Forced to compete for operating room time with other surgeons, he said that he and his colleague could complete only one or two operations on some days, meaning that patients whose cases were not emergencies could go months or even years before completing necessary treatment.

“Scarce resources are simply not being spent properly,” Dr. Sriharan concluded, citing a shortage of nurses and anesthesiologists in the hospital where the single microscope available is old and breaking down.

The two surgeons are sharply critical of Canada’s health care system, which is driven by government-financed insurance for all but increasingly rations service because of various technological and personnel shortages. Both doctors said they were fed up with a two-tier medical system in which those with connections go to the head of the line for surgery.

Here is another:

There was a net migration of 49 neurosurgeons from Canada from 1996 to 2002, according to the Canadian Institute for Health Information, a large loss given that there are only 241 neurosurgeons in the country.

My take: It is only going to get worse.

More on placebos

Alex, in his blog post from earlier today, makes a good point about placebos. Sometimes the patient is getting better anyway, and we should not attribute this effect to a placebo.

Note, however, that the best-known “anti-placebo” study is not as strong as is commonly believed. It relies heavily on a meta-analysis of other studies. Placebos appear to be effective in relieving the sufferer of pain, if nothing else. And placebos appear more effective when the ailment is continuous rather than discrete. Furthermore it is unclear how many people in the so-called no-treatment groups in fact received no treatment at all.

Here is a defense of the placebo effect. Placebos also have measurable effects in the brain, comparable to those of drugs, though weaker or less persistent.

Robert Ehrlich’s Eight Preposterous Propositions offers a very good survey of the placebo debates. His conclusion:

In summary, the [critical] study may have shown that the placebo is not as powerful as some observers would believe, but it certainly is far from powerless.

By the way, did you know that people can become addicted to placebos, or suffer from harmful “side effects”? I’ll try to write more on “nocebos,” or negative placebos, soon, at least provided that my mental attitude holds up.

Defining the Placebo Effect Carefully

I agree with Tyler that there is some serious evidence for placebo effects, especially although not exclusively for subjective components of disease. But the evidence is usually overstated because it is confused with the natural tendency of sick people to get better. A typical medical study, for example, will compare the results of a new drug against a placebo. The improvement in health of those on the placebo is then labeled “the placebo effect” – but this is wrong. To correctly identify the effect of the placebo one needs three randomly selected groups – a treated group, a placebo group and a non-treated group. The effect of the placebo per se is then measured by the health differences between the placebo and non-treated group. Although spontaneous healing effects are large, placebo effects when measured correctly tend to be small although not non-existent.

Fingers

Of the strange beliefs that Tyler examines he finds craziest the idea that slender hands might signal artistic ability. Maybe, but you know what they say about truth and fiction. Recent research indicates that finger length relative to height and the relative length of the ring to index finger can predict a great deal about male depression and intelligence, who is most at risk for heart attacks and sexual orientation. The theory is that testosterone and other hormones like androgen are the direct causes but fingers are a particulary good marker for hormone production.

Dollars for Donors

The shortage of human organs for transplant grows worse every year. Better immuno-suppressive drugs and surgical techniques have raised the demand at the same time that better emergency medicine, reduced crime and safer roads have reduced organ supply. As a result, the waiting list for organ transplants is now 82,000 and rising and more than 6000 people will die this year while waiting for a transplant.

The economics of the shortage are so obvious that one popular textbook, Pindyck and Rubinfeld’s Microeconomics, uses the organ shortage to explain the effect of price controls more generally!

Perhaps because the shortage is growing, opposition to financial compensation for cadaveric donation (compensation for live donors is a distinct issue) appears to be lessening. The AMA, the American Society of Transplant Surgeons and the United Network for Organ Sharing have agreed that tests of the idea would be desirable. (A group of clerics, doctors, economists (I am a member) and others has formed to lobby for the idea – see our letter to Congress.) Currently, even tests are illegal but Representative James Greenwood (R, Pa.) has introduced a bill (H.R. 2856) that would create an exception.

Aside from the obvious benefits of saving lives, financial compensation for organ donation would likely save money. Here is a back-of-the-envelope calculation. There are some 285,000 people on dialysis in the US. Transplants are cheaper than dialysis by something like $10-$25,000 per year. About a quarter of those on dialysis are on the waiting list but perhaps as many as half could benefit from a transplant (fewer people are put on the list because of the shortage.) Let’s take the lower numbers. Assume that a quarter of the patients on dialysis could benefit from a transplant and that cost savings are $10,000 a year for five years. Then ending the shortage would save 3.5 billion dollars. Note again that this is a lower estimate. How much would it cost to end the shortage? No one knows for certain but I think a $5000 gift to the estates of organ donors would increase supply enough to greatly alleviate the shortage – that would involve doubling the supply to 12,000 for a paltry cost of $60 million. If this is not enough – raise the gift – anyway you cut it, the savings from dialysis exceed the costs of compensating donors by a large margin.

We should in fact count the value of the lives saved. If we can save 6000 lives and value each life at 3 million dollars (a lower value than what the US government typically uses in its calculations) then that is a further gain of 18 billion dollars.

A Tragedy of the Commons?
Economics provides another way of looking at the crisis. Currently we have organ socialism – anyone who needs an organ is allowed access to the organ pool regardless of whether or not they contributed to the upkeep. As with other resources owned in common we get over-exploitation and under-investment. Consider, instead a “no-give, no-take policy” – only those who have previously signed their organ donor cards are allowed access to the pool. Not only is this more moral than the current policy it creates an incentive to sign your organ donor card. Signing your card becomes the ticket to joining a club – the club of people who have agreed to share their organs should they no longer need them. Equivalently signing your organ donor card becomes analogous to buying insurance. I discuss the idea further in Entrepreneurial Economics.

An organ club has in fact been started – I am not just an adviser, I’m also a member! You can join too at www.lifesharers.com.

Where are all the new drugs?

The NYTimes reports that “introductions of new drugs plummeted last year to 17 from a high of 53 in 1996, despite a near doubling in annual research spending, to $32 billion.” The Times blames lost lab productivity from mergers. Based on close second-hand experience – my wife is a microbiologist who worked at a pharmaceutical firm as it underwent a merger – I can attest to the fact that mergers create havoc. Reaping the potential economies of scale and scope that drive the merger requires that product lines be discontinued and new lines of hierarchy established. But the power struggles involved in the transition are dissipative and disheartening. It’s not uncommon for some research programs to be canceled and then started again as new coalitons form. The uncertainty alone is draining. The best of the researchers have no stomach for this ordeal and jump ship.

The Times gets a number of things wrong, however. It can take a dozen or more years to research, develop and get a new drug approved so it makes no sense to compare this year’s research spending with this year’s output. The fact that research spending is up even though current output is down is a positive signal of potentially better things to come.

The Times also misses the fact the FDA was approving drugs faster in the late 1990’s than for many decades previously. The FDA got burned, however, as Pulitzer prize-winning critics accused it of endangering the public. Sadly, the FDA learned its lesson and slowed down. (See here for more on FDA incentives and why the Pulitzer prize committee did us all a disservice.)

Finally, the Times says nothing about why the mergers are taking place. One reason is the rising cost of pharmaceutical research. It now costs $900 million dollars to bring the average new drug to market. Firms are merging in order to better control these costs and diversify their risks. FDA reform could lower these costs.

Doctors are very ignorant of statistics

Here is a bit from Gerd Gigerenzer:

The science fiction writer H G Wells predicted that in modern technological societies statistical thinking will one day be as necessary for efficient citizenship as the ability to read and write. How far have we got, a hundred or so years later? A glance at the literature shows a shocking lack of statistical understanding of the outcomes of modern technologies, from standard screening tests for HIV infection to DNA evidence. For instance, doctors with an average of 14 years of professional experience were asked to imagine using the Haemoccult test to screen for colorectal cancer. The prevalence of cancer was 0.3%, the sensitivity of the test was 50%, and the false positive rate was 3%. The doctors were asked: what is the probability that someone who tests positive actually has colorectal cancer? The correct answer is about 5%. However, the doctors’ answers ranged from 1% to 99%, with about half of them estimating the probability as 50% (the sensitivity) or 47% (sensitivity minus false positive rate). If patients knew about this degree of variability and statistical innumeracy they would be justly alarmed.

The lead is from Crooked Timber, through BlackTriangle.org.

Will life extension increase risk aversion?

Scientist Tom Johnson says that humans someday might live to 350 years old. Aubrey De Grey argues that as our lifespans become longer, we might stop taking high-speed automobile trips. Why risk losing so much, and after all, what would the hurry be?

FuturePundit suggests that perhaps our level of risk-taking behavior is regulated by our biology and hormonal systems. So if driving a car doesn’t “feel too risky” now, living to 350 won’t change this, perhaps we were never making an intertemporal calculation in the first place. Furthermore, it is young males who take the most risks, and they have large numbers of years left to lose. So giving us more years might not change our behavior that much. FuturePundit then wonders how drugs and neuroscience engineering might change this conclusion. What if you could take drugs that would make you more averse to risky behavior? Might you then, sitting alone in your room, ponder your remaining 320 years and decide to clutch on to them?

Cannabis Emptor

When goods are prohibited, quality tends to fall because of lack of competition and legal recourse. Quality in illegal markets, however, may still beat that available from government production. Health Canada spends millions of dollars growing marijuana for distribution to patients with medical need. The government grown pot is so awful, however, that patients are returning their 30 gram bags and asking for refunds! The government certifies and advertises that their product contains 10.2% THC but independent labs report only 3% THC. Furthermore, the government pot is contaminated with lead and arsenic. “This particular product wouldn’t hold a candle to street-level cannabis,” said Philippe Lucas of Canadians for Safe Access, the group that sponsored the tests. Thanks to Eric Crampton for alerting us to this story.