Unhealthful News 181 - Avastin likely to be de-listed for treating breast cancer; if only they explained why

This week there was some seriously unhelpful health news.  One of the most talked about bits of health news of the last few days (example, example) is that an FDA committee concluded that the drug Avastin used to treat several types of cancer, is a bad choice for treating breast cancer.  It is likely that the FDA will therefore withdrawal approval for that use.

I was curious about what was known, what the concerns were, what motivated the decision, what will happen, etc., so read some of the news and health pundit reports on the topic.  I could have kept going, and probably pursued a more technical angle, but I started to find it more interesting to realize that I was learning almost nothing from what I was reading that was not contained in the headline. 

The committee's unanimous judgment was that the risk outweighed the benefits.  The only counter-arguments discussed were breast cancer patients who believe they have benefited from the drug begging not to lose it.  Today it was announced that Medicare would still cover its use for breast cancer (because it will still be approved for other cancers, it will be on the market and FDA regulations do not prevent it from being used "off label").  This brings up some questions.

"Risks outweigh the benefits" can have rather different meanings.  One of them is the subtle "if you use this drug rather than another then, adding up all the outcomes including cures and side effects, you are a bit worse off."  That is a case where nothing much can be done except look at the overall statistics and go with them.  But there are other variations, an extreme version of which might be, "this drug saves 5% more of those who take it for a year compared to the alternative, but it rapidly kills 6% of those who take it."  There is no practical difference among these unless it is possible to figure out if someone is in the group that benefits or suffers from the choice, and presumably that has already been done based on demographics and details of the cancer to the extent currently possible. 

There is one other possibility, where it is possible to start a treatment and figure out whether it is going well.  I have no idea whether that might be possible in this case.  You would think that after reading thousands of words analyzing the regulatory decision some information might have creeped in, but no.  Some of the severe side effects mentioned (digestive system perforations, bleeding) are such that they can be detected and perhaps treatment can be changed, but perhaps it is then too late or changing the treatment is not safe.  I am sure these are known, but no on reported them. 

Some pundits complained that the news stories took many paragraphs to get to the most important point, that the studies show that the drug does not improve survival.  I agree that this is the most important point.  But I take issue with the implication that this is all that is useful to know.  There is talk about continued research to find if there is a subset of breast cancer victims who might benefit; that is what pharma companies always want to do in cases like this.  But it might be possible to identify cases that are benefiting.  Or it might not.  The news and pundits appear to be utterly silent on that point.


This is interesting because of the amount of attention devoted to women who were asking that the drug not be taken away from them because they believed it was helping.  Not a single report or analysis I saw argued made the obvious point, that they have no way to know that because they have no idea what would be happening if they were not taking the drug.  (There is evidence that the drug slows cancer growth even while not improving longevity, which would create the appearance of benefit.)  On the other hand, no one suggested it might be the case that this subset is right about them being the ones who benefit (which would mean that others have been hurt because we know the balance is "no benefit").  Perhaps it is the case that if someone escapes the nasty obvious side effects then having the drug is better than not having it.  That is kind of like the 5%/6% scenario I made up, wherein if it does not kill you early it is helping you.  Presumably this information exists, but the allusions in the news to there being some slight prognosis improvements for some stages of cancer were not very useful.

This brings up a second question, which is why anyone expert would suggest continued use is a good idea.  Individual consumers are often irrational, and mistakenly think that averages do not apply to them, and think they can see causation (that the drug is causing them to be healthier) when it is really too complicated to see.  Individual medics are no better.  But Medicare's policy decision implies that someone who is supposed to understand these things thinks it is wise to keep using Avastin to treat breast cancer.  Yet to the news reader, there seems to be no basis for expert disagreement in the discussion.  If there is no benefit, then there is no benefit.  Again, presumably I could dig deeper into expert discussions and make sense of this, but how can it be that the news reports implicitly tell us there is this controversy, but no one thinks to report the basis of disagreement?

The only consternation reported was not about the challenge of scientific disagreement, but what to do with all of those poor women who are benefiting from the drug and testified in favor of keeping the indication.  (Answer: Um, let them keep taking it if they really want it so much?  It is not being banned after all.)  The committee hearing was even called a "death trial" for them (as in "death panel"), because they were not just statistics.  Some local news stories picked up individual examples of the human interest drama of those who will be deprived of this wonderful drug.  Oh, where to start.

We expect superficial news reporting that emphasizes uninformative stories over useful statistics.  In is pretty typical that the useful statistics are buried in the article.  But in this case, nothing that was reported allows the reader to have any idea if the anecdotal claims have any basis, or should have any effect on decision making.  There is the usual spate of statements like "the plural of anecdote is not data" from self-styled pundits, but that statement is not actually true.  There are plenty of situations where anecdotes about the non-average cases are informative.  There are cases where off-label use of makes sense for an identifiable subset, and so Medicare should pay for it.  Is this one of those cases.  Maybe someone understands these points and knows the answers, but they are apparently not among those writing the news and commentary.

Unhealthful News 180 - Study of "No Smoking Day" may be a new low in bad epidemiology and health economics

Ok, that is probably not true, given how much other bad anti-tobacco "research" there is out there.  But this is a really good one.  It was so good I stole it from today's weekly readings in THR post so that I could expand on it here.

It was published in the quasi-journal Tobacco Control, of course.  I will provide the entire abstract here so you do not have to bother with the link.
How cost-effective is ‘No Smoking Day’?
D Kotz, J A Stapleton, L Owen, R West 
Participants: A total of 1309 adults who had smoked in the past year who responded to the surveys in the month following NSD (April 2007–2009) and a comparison group of 2672 adults who smoked in the past year who responded to the survey in the two adjacent months (March and May 2007–2009). 
Main outcome measures: The number of additional smokers who quit permanently in response to NSD was estimated from the survey results. The incremental cost-effectiveness ratio (ICER) was calculated by combining this estimate with established estimates of life years gained and the known costs of NSD. 
Results: The rate of quit attempts was 2.8 percentage points higher in the months following NSD (120/1309) compared with the adjacent months (170/2672; 95% CI 0.99% to 4.62%), leading to an estimated additional 0.07% of the 8.5 million smokers in England quitting permanently in response to NSD. The cost of NSD per smoker was £0.088. The discounted life years gained per smoker in the modal age group 35–44 years was 0.00107, resulting in an ICER of £82.24 (95% CI 49.7 to 231.6). ICER estimates for other age groups were similar. 
Conclusions: NSD emerges as an extremely cost-effective public health intervention.
Taking this from the top, we have to start by observing that they are claiming that about 10% of all smokers attempted to quit each month.  This indicates either some very faulty data or such an expansive definition of "quit attempt" (like "I woke up and decided I was going to quit, but I started again during my morning break") that it is meaningless.

Moving on, they assume that the entire observed difference is neither random nor the result of Easter/Lent, Passover, spring holidays, the misery of March, or anything else that might make April different from nearby months.  It seems like these might make a wee bit more difference than an arbitrary declared day that most people pay no attention to.  It is kind of interesting that they did not give us a month-by month breakdown, which we might have expected if the month with "No Smoking Day" were the global or even local minimum.

Beyond that, their interpretation of what NSD entails is quite silly.  They treat it as if it is some kind of medical intervention that is independent of other causes of quitting, but really it is (at most, even if it really works) a focusing event, causing people who are considering quitting soon to say "ok, I am going to do it that day".  So the effect, if there really is one, is to move quit attempts from May and June back to April.  Perhaps not of trivial import (remember that smoking for just a couple more months is as unhealthy as using smokeless tobacco for your entire life), but not the same as causing quitting that would not have otherwise happened.

And this says nothing of their their magical ability to detect permanent cessation from a cross-sectional survey.  Even if they have some standard prediction about permanence, quitting for different motivations, like say a focusing event, will inevitably have different permanency rates.

As if this were not bad enough, where they really jump the shark is the cost-effectiveness analysis.  Reporting the cost of a declared focusing day per smoker is LOL funny.  I wonder how much National Kale Week cost per meal at which kale was served; I will bet it was quite a bargain too. 

That "ICER" is the "incremental cost effectiveness ratio", which measures the cost-effectiveness of an intervention as compared to an alternative it could replace that is more cost effective (so a better deal) but less effective in total.  In other words it accomplishes an analysis like: "if we are going to take driver protections one step beyond seatbelts and add airbags, which are much more expensive but will save a few more people, we should make sure to not give airbags credit for the people that seatbelts alone would have saved anyway by comparing them to no restraints at all."  What makes this funny is that they pretend to be using a somewhat complicated good measure, one that is often not done creating erroneous results (e.g., airbags are measured against no restraints at all; pharmaceuticals are measured against placebos rather than existing effective treatments), to look at something that they got totally wrong.  In this case, the alternative that is crowded out by NSD (like airbags+seatbelts crowds out seatbelts-alone) is they same people quitting a bit later, which they completely ignore.  So what they claim is ICER is really just the most basic, and misleading, cost-effectiveness calculation that pretends nothing would motivate quitting were it not for NSD. 

So they go on to calculate the cost-effectiveness, not as £80/life-year-saved, but £82.24.  Even if their estimate of the effect of the intervention were as precise as the 2.8 percentage points they report (which is not even possible given that they are basing this on only a few hundred events) they could not get precision even to the first significant figure, let alone the fourth:  The guess – "estimate" would give it too much credit – about how many life years will be saved by someone quitting (again, even pretending that NSD caused it, and their estimate of permanent quits is based on anything, and that it would not have happened a month later even without NSD) requires assumptions about the next half-century of medical technology and other health effects.  It cannot be reasonably guessed-at within a factor of two, let alone to one part in 10,000 as they imply.  Someone develops a cure for cancer or emphysema, and the benefits plunge; some other breakthrough extends life by 100 years so long as you do not get cancer or emphysema and the benefits shoot up.

About the only thing that can really be said about their conclusion is that there is no doubt that NSD is more cost-effective than funding people who write articles for Tobacco Control.

Yes, this is what passes for science in anti-tobacco.  Is it any wonder that they can reconcile "hundreds of millions of people are not quitting" with "a tobacco free world by 2030" or whatever?  It would be humorous if it was not so incredibly damaging.  Oh let's be honest:  In spite of being incredibly damaging, it is frackin' hilarious.