Month: December 2007

Can Anti-Depressants Cause Suicide?

Seth Roberts4 Comments

Many parents have said yes. David Healy, a Scottish psychiatrist, prompted by those stories, did a small experiment in which undepressed persons took anti-depressants. About 10% of them started having suicidal thoughts. Drug companies and the University of Toronto (where Healy had been offered a job) reacted very badly to this information, as Healy describes in Let Them Eat Prozac. An article in the latest issue of the American Journal of Psychiatry by David Leon, a biostatistician on the FDA oversight panel, describes why he voted to extend a warning about this from children (< 18 years old) to young adults (18-24 years old). This was the main data:

risk ratios by age

What’s shown is the odds ratio for a report of suicide ideation or behavior, comparing those who got anti-depressants with those who got placebos. An odds ratio of more than 1 means greater risk in those who got anti-depressants. The red bar is from a different study. When different ages are lumped together there is no increase in risk but that hides opposing tendencies at high and low ages.

The article contains this curious sentence: “The results did not provide definitive evidence of risk, yet they failed to demonstrate an absolute absence of risk.” No possible results could “demonstrate an absolute absence of risk” so it is unclear what Dr. Leon meant. Later he writes: “My vote to extend the black box warning to young adults was based on concern that risk of suicidality could not be ruled out and, given the widespread antidepressant use, even a small risk must not be ignored.” Yes, he has it backwards: The data do not “fail to rule out” suicide risk (no possible data could “rule out” such risk, i.e., show the risk is zero); they manage to overcome a barrier to show it’s there. And yes, he’s congratulating himself (”even a small risk must not be ignored”) for doing his job.

Uh-oh. That someone — a biostatistician, no less — in such a powerful regulatory position fails to understand basic concepts is bad enough; to make things worse, Dr. Leon has received money from three of the companies (Eli Lilly, Organon, and Pfizer) he oversees.

Related post by Andrew Gelman.

Dr. Dermatologist, Meet Governor Huckabee

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Since the 1960s, this has been the standard conversation in dermatology offices:

PATIENT I think Food X causes acne. After I eat Food X, I break out.

DOCTOR There’s no link between food and acne, but if something bothers you, don’t eat it.

Here is Governor Huckabee campaigning for President:

“If you want to believe that you and your family came from apes, that’s fine,” Huckabee said after an early debate. “I’ll accept that. I just don’t happen to think that I did.”

The dermatologists made a mountain out of a molehill (the diet/acne question hadn’t been carefully studied). Huckabee made a molehill out of a mountain.

Academic Horror Story (Johns Hopkins University)

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I previously blogged about ICU checklists. Atul Gawande has written another excellent article about them, this time an editorial in the New York Times:

A year ago, researchers at Johns Hopkins University published the results of a program that instituted in nearly every intensive care unit in Michigan a simple five-step checklist designed to prevent certain hospital infections. It reminds doctors to make sure, for example, that before putting large intravenous lines into patients, they actually wash their hands and don a sterile gown and gloves.

The results were stunning. Within three months, the rate of bloodstream infections from these I.V. lines fell by two-thirds. The average I.C.U. cut its infection rate from 4 percent to zero. Over 18 months, the program saved more than 1,500 lives and nearly $200 million.

Yet this past month, the Office for Human Research Protections shut the program down. The agency issued notice to the researchers and the Michigan Health and Hospital Association that, by introducing a checklist and tracking the results without written, informed consent from each patient and health-care provider, they had violated scientific ethics regulations. Johns Hopkins had to halt not only the program in Michigan but also its plans to extend it to hospitals in New Jersey and Rhode Island.

The government’s decision was bizarre and dangerous. But there was a certain blinkered logic to it, which went like this: A checklist is an alteration in medical care no less than an experimental drug is. . . . A checklist may require even more stringent oversight [than drug tests], the [OHRP] ruled, because the data gathered in testing it could put not only the patients but also the doctors at risk — by exposing how poorly some of them follow basic infection-prevention procedures. . . .

A large body of evidence gathered in recent years has revealed a profound failure by health-care professionals to follow basic steps proven to stop infection and other major complications. We now know that hundreds of thousands of Americans suffer serious complications or die as a result. It’s not for lack of effort. People in health care work long, hard hours. They are struggling, however, to provide increasingly complex care in the absence of effective systematization.

Excellent clinical care is no longer possible without doctors and nurses routinely using checklists and other organizational strategies and studying their results. There need to be as few barriers to such efforts as possible. Instead, the endeavor itself is treated as the danger. . . . Scientific research regulations had previously exempted efforts to improve medical quality and public health — because they hadn’t been scientific. Now that the work is becoming more systematic (and effective), the authorities have stepped in. And they’re in danger of putting ethics bureaucracy in the way of actual ethical medical care.

Not “in danger of” — they have put “ethics bureaucracy” ahead of patient safety. In a big way.

Academic Horror Story (Duke University)

Seth Roberts6 Comments

From Until Proven Innocent by Stuart Taylor and K. C. Johnson, about the Duke lacrosse case:

The Duke president addressed the [lacrosse] team for the first time since May a few weeks into its fall practice. . . . When Brodhead opened the floor for questions, Read Seligmann’s former roommate, Jay Jennison, spoke up. He said that all of the team had learned much from the case . . . “What have you and the administration learned?” Jennison asked Brodhead. . . . Brodhead responded, “What do you think I should have learned?”

Head of a prestigious institution of higher learning resistant to learning or at least admission of learning. Curious.

Tulane University.

An SLD Story for the Coming Year

Seth Roberts1 Comment

My dad has diabetes, and I casually got Amazon.com to send him the Shangri-La Diet book. I left him a message saying (still very casually) “I came across something that you might find interesting. The book is in the mail. Talk to you soon”.

A few weeks later he (casually) mentioned that he had started the oil, and was now physically incapable of overeating.

A few more weeks later, and he reports that he is unable to finish his breakfast in one sitting – he has to eat half, go work for a few hours, then finish his breakfast.

I’m elated.

My father has been compared to Homer Simpson. Both in the “get thrown out of Pizza Hut on all-you-can-eat night” and in the “awwww, my stomach hurts… I shouldn’t have eaten that packet of gravy that I found in the parking lot” departments.

From the SLD forums.

Irritability and Coca-Cola (continued)

Seth Roberts1 Comment

John Keltner, an M.D./Ph.D. at Oxford, guest-blogged earlier about a self-experiment to measure the effect of Coke on his mood. Below he describes his results in more detail.

I did a self-experiment to measure the mood and hunger effects of consuming 30 oz of Coke, Diet Coke With Caffeine, and Diet Coke Without Caffeine. I used two numerical rating scales. For the mood scale 0 represented profound dysphoria, 5 neutral mood, and 10 profound euphoria. For the hunger scale 0 represented profound hunger, 5 no hunger or fullness, 10 profound fullness.

Each day before dinner (after ~ 7 hours of not eating anything but water), I measured my mood and hunger/fullness at four times: right before drinking 30 oz of soda, right after drinking the soda, 10 min after, and 20 min after.

I collected the data in two ways: blinded and not blinded. The 3 drinks were consumed in a random order.

The experiment lasted 25 days – one drink per day.

At the end of the 25 days there were a couple of measurement categories with only 2 or 3 data points, so I have combined the blinded and not blinded data for the purposes of presenting the data here.

The figures below show means and standard errors.

mood ratings vs time

fullness ratings

Within 10 minutes (and stronger at 20 minutes) there appears to be a significant change in mood ratings for the sugar and caffeine coke drink compared to the non-sugar and non-caffeine coke drink. Furthermore, it appears that caffeine alone was able to cause an increase in mood at the 10 minute and 20 minute time points between diet+caf coke vs diet w/ no caf coke. Finally, it appears that effects of sugar and mood are additive.

There was not a large difference in the fullness ratings between the three different drinks.

It is also notable that mood and fullness were markedly increased for all drinks immediately after consuming the drinks. Presumably this immediate increase in fullness and mood has more to do with the immediate taste or volume affects of the drinks and less to do with the calories or caffeine in the drinks.

In my next experiment investigating mood effects of sugar and caffeine I will reduce the number of parameters in my experiment. I spent a month collecting this data and a fair amount of effort (blinded data are hard to collect). Because I chose three types of coke drinks (sugar+caf, no sugar but caf, no sugar and no caf), two parameters to examine (hunger and mood), and two conditions (blind and non-blinded) my data points were spread too thin over the categories. Next experiment I will choose just two drinks (caf vs no caf), one condition (blinded), and I would focus on mood instead of hunger.

This experiment leads me to believe that a number of smaller experiments are more effective than one large experiment – at least in the beginning.

I would like to thank Seth Roberts (a lot!) for his generous helpful suggestions as I pursued this self experiment. I initiated the experiment on my own, but I would not have finished it without Seth’s help.

The Power of Placebos Over Health Journalists

Seth Roberts7 Comments

In the New York Times, Abigail Zuger, an M.D., recently reviewed a book called Snake Oil Science: The Truth About Complementary and Alternative Medicine by R. Barker Bausell — the “truth” being, if I read Zuger correctly, that it’s all baloney. Zuger calls the book “immensely educational”. Not educational enough:

Dr. Bausell starts out with the story of his late mother-in-law, Sarah, a concert pianist who developed painful arthritis in her old age and found her doctors to be generally useless when it came to satisfactory pain control. “So, being an independent, take-charge sort of individual, she subscribed to Prevention magazine, in order to learn more about the multiple remedies suggested in each month’s issue” for symptoms like hers.

What ensued, according to Dr. Bausell, was a predictable pattern. Every couple of months Sarah would make a triumphant phone call and announce “with great enthusiasm and conviction” that a new food or supplement or capsule had practically cured her arthritis. Unfortunately, each miracle cure was regularly replaced by a different one, in a cycle her son-in-law ruefully breaks down for detailed analysis.

Neither Bausell nor Zuger notice two problems here: (a) The alternative treatments worked better than the conventional ones. They didn’t provide permanent relief, true, but apparently conventional medicine (”useless”) didn’t provide any relief. Something is better than nothing — and something is wrong with Bausell’s interpretation of this story. (b) Why didn’t the conventional treatments benefit from the placebo effect?

That Zuger thinks this story supports her claim that the book is good suggests the power of pre-conceived notions, not the power of placebos.

The book is published by Oxford University Press. Bausell has a Ph.d. in Educational Research and works as a methodologist.

Not only do Bausell and Zuger fail to see what the mother-in-law story means, they fail to grasp a larger point: Skeptics are a dime a dozen. The attitude in short supply is sophisticated appreciation.

Thanks to Dave Lull and Hal Pashler.

Speaking of Gifts

Seth Roberts9 Comments

Yesterday I knocked something off a table and caught it before it fell very far. “Nice catch,” said an observer. I too was surprised. Today the same thing happened. Something fell and I surprised myself by catching it. I think it’s the omega-3. Tests showed that flaxseed oil reduces my “simple reaction time” — the time to push a button as quickly as possible in response to a signal.

How Doctors Tell Family Members that the Patient has Died

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The last issue of the BMJ each year is a “Christmas issue” with humorous and seasonally-themed articles. This year’s Christmas issue has an article about how doctors tell family members that the patient has died. The execution is very flawed; for example, it’s hard to tell how fictional it is. I mention it because a study of how doctors actually do this and how it changes with experience — comparing young and old doctors, for example — would be fascinating.