Science and Medicine

Archive for Science and Medicine

Changing Climate, Changing Infections

I will state my bias up front.  I am convinced by the preponderance of data in favor of man made global warming.  At the most simplistic level, I can’t see how converting humongous tons of fossil fuel into C02 and dumping it into the the atmosphere cannot have effects on the climate.  To my mind its like determining vaccine efficacy or evolution.  Plausible mechanism(s), good basic science, multiple studies using different lines of evidence that all come to the same conclusion.  There are lots of fine points and nuances to be worked out, but the basic truth is reasonable and well defined. Infectious diseases lend some validation to the concept that world is warming, since with global warming will come a variety of infectious diseases.
It is one big IF THEN statement.  IF global warming, THEN infections.  Of course the if the IF is not true, then the THEN doesn’t follow.
There is the weather, which the Action Channel News never seems to get right, and I will spare you the Mark Twain quote even though I think he is our best writer ever,  and there is the climate, the summation of weather over time.
Interestingly, infections have probably altered climate for short periods of times.  Through history humans burned trees releasing C02, chopped down forests for agriculture and raised animals, releasing methane.  As humans populations increased, both C02 from burning and methane from animals increased as well.  Every now and then large numbers of people have died off.  It happen when Columbus et. al. brought infections to the New World and when plague came to the Old.  People died.  Maybe 90% in the Americas (estimates vary widely) and 2/3’s of Europe died.  As a result, burning and agriculture decreased, decreasing emissions and forests grew back, sequestering C02.  And temperature rise slowed or decreased (
“Abrupt reversals of the slow CO2 rise caused by deforestation correlate with bubonic plague and other pandemics near 200-600, 1300-1400 and 1500-1700 A.D. Historical records show that high mortality rates caused by plague led to massive abandonment of farms. Forest re-growth on the untended farms pulled CO2 out of the atmosphere and caused CO2 levels to fall. In time, the plagues abated, the farms were reoccupied, and the newly re-grown forests were cut, returning the CO2 to the atmosphere…Moreover, if plague caused most of the 10-ppm CO2 drops… it must also have been a major factor in the climatic cooling that led from the relative warmth of 1000 years ago to the cooler temperatures of the Little Ice Age.”
Like all good scientists, he notes the problems with his conclusions
“A more complete assessment of the role of plague- driven CO2 changes in climate change during the last millennium would require a narrowing of uncertainties in both the spatial and temporal occurrence of plague and in the amount of farm abandonment (and reforestation), as well as a resolution of the inconsistencies among the CO2 trends from different Antarctic ice cores.”
This kind of study will never be reported in the Atlantic; too much nuance.
It is not the correction for global warming I would suggest, an Earth Abides die off of humans.  But it is an fascinating association between infectious human deaths and global warming.
As the weather changes, for a week, a season, or a over longer period of time, the incidence and distributions of  infections change.  Infections could increase or decrease due to something as simple as temperature or humidity.
Or it could be more complex.  Increase rainfall could lead to more food, which could lead to a boom in the rodent population leading to more interactions of humans and mice and the next thing you know you have bubonic plague in India or Hanta virus outbreak in the four corners of the US.
The daily weather makes a difference in infection risk.  My favorite example is Legionella pneumonia, which increases shortly after thundershowers and humid weather.  It explains why we do not have a lot of Legionella in the NW despite all the rain; it is rarely hot and humid.
In Philadelphia  Legionella
“Cases occurred with striking summertime seasonality. Occurrence of cases was associated with monthly average temperature (incidence rate ratio [IRR] per degree Celsius, 1.07 [95% confidence interval [CI], 1.05-1.09]) and relative humidity (IRR per 1% increase in relative humidity, 1.09 [95% CI, 1.06-1.12]) by Poisson regression analysis. However, case-crossover analysis identified an acute association with precipitation (odds ratio [OR], 2.48 [95% CI, 1.30-3.12]) and increased humidity (OR per 1% increase in relative humidity, 1.08 [95% CI, 1.05-1.11]) 6-10 days before occurrence of cases.”
I ask the housestaff to look for Legionella after thundershowers and I usually get a case or two, although it may just be due to increased diagnostic testing.
Can you catch a cold when the weather is cold? Maybe.  It has been a topic of interest for years (
“The average outdoor temperature decreased during the preceding three days of the onset of any RTIs, URTI, LRTI or common cold. The temperature for the preceding 14 days also showed a linear decrease for any RTI, URTI or common cold.  (”
More interesting are the infections associated with El Nino oscillations, where the ocean temperatures vary on a 3 to seven to year cycle, leading to alternating wet and dry weather.  As a result
“In North America, El Niño creates warmer-than-average winters in the upper Midwest states and the Northwest, thus reduced snowfall than average during winter. Meanwhile, central and southern California, northwest Mexico and the southwestern U.S. become significantly wetter while the northern Gulf of Mexico states and Southeast states (including Tidewater and northeast Mexico) are wetter and cooler than average during the El Niño phase of the oscillation. Summer is wetter in the intermountain regions of the U.S. The Pacific Northwest states, on the other hand, tend to experience dry, mild but foggy winters and warm, sunny and early springs.”
Changes due to the El Nino lead to changes in the incidence of a huge variety of infections: an example, I think, from WHO.
Climate change will affect the distribution of disease vectors such as insects and snails.  Vectors may thrive with increased temperatures or they may die off, but more likely the vectors, like mosquitos, will move.  It has been estimated that half of everyone who has every died has died from a mosquito borne illness (I admit I heard this numoerous times at ID lectures but do not have reference, at least there is a solution .  As it gets warmer, mosquitos can either go up in elevation or North.  It seems that they are doing both.
– Dengue has appeared at higher altitudes than previously reported in Costa Rica (at 1,250m),and in Colombia and India (at 2,200m).The previous range was temperature limited to approximately 1,000 metres above sea level.
– In Mexico, the dengue vector (Aedes aegypti) has been detected at 1,600 metres; transmission of dengue was unknown above 1,200m before 1986. There have been cases of dengue near or above the altitude or latitude limit of transmission and would be vulnerable to the small increases in temperature that have occurred across these regions.
– Other examples of climate-related changes in the prevalence or distribution of pathogens and their vectors include the resurgence of Mediterranean spotted fever in Spain and Italy, the recent epizootic of African horse sickness in Iberia,the resurgence of plague in parts of southern Africa,increased incidence and geographic spread of algal blooms, outbreaks of opportunistic infections among seals,and the spread and establishment of pathogens and vectors in Switzerland.
– Dengue has, by serology, infected 40% of the populations of Brownsville Texas, as the disease slowly moves north.
“In the fall of 2004, during a period of endemic dengue transmission, a cross-sectional survey was conducted in these two cities,4 and dengue incidence and prevalence were measured. In Brownsville, the incidence was 2%, which, if extrapolated to the 2005 population of the city (using the 95% confidence interval), projected between 837 and 5,862 recent infections. Similarly, the prevalence was 40%, with a range from 56,948 to 75,372; these values are relatively similar to those obtained from Brownsville in 2005.”
More than mosquito born illnesses are changing in prevalence.  Hanta is increasing in Belgium.  There has been increased temperature which has lead to increased broadleaf trees, with increased seeds, with increased voles, which carry Hanta, which infected humans to cause renal failure (
Oceans are getting warmer and supporting infections.  Vibrio was not found in Alaskan oysters as the water was too cold.  The water temperature was always less than 15 C.  No longer.  The mean temperature has increased each year since 1997  and now supports the growth of V. parahaemolyticus with resultant outbreaks (  Many other infectious diseases are increasing as well
However, not all is doom and gloom.  Some infections may fade with global warming. For example, RSV may be disappearing as England warms.
“The seasons associated with laboratory isolation of respiratory syncytial virus (RSV) (for 1981–2004) and RSV‐related emergency department admissions (for 1990–2004) ended 3.1 and 2.5 weeks earlier, respectively, per 1°C increase in annual central England temperature ( and .043, respectively). Climate change may be shortening the RSV season.”
Diseases that may increase in the US or become endemic again include malaria, dengue, and Leishmaniasis.  A 4 degree rise in temperature could allow dengue to exist as far north as Winnipeg and malaria to be in all of Europe. Seems to be a good trade off to me: more dengue and malaria, less RSV.
Good times for an infectious disease doctor.
These studies are representative of the literature, not a comprehensive review of the topic.  Personally, I find this adjunctive data compelling  support of global warming, at least over recent times (deliberately worded to not commit to the meaning of recent.)  This does not include all the other potential interactions between human behaviors and changes in the weather to result in an increase in infectious diseases.  Even simple local changes can lead to the unexpected increase in the risk of diseases.
“Adjustable rate mortgages and the downturn in the California housing market caused a 300% increase in notices of delinquency in Bakersfield, Kern County. This led to large numbers of neglected swimming pools, which were associated with a 276% increase in the number of human West Nile virus cases during the summer of 2007.”
All the neglected pools became mosquito breeding grounds, and the disease spread was exacerbated in part by a drought that altered bird populations from resistant finches to susceptible sparrows that were not immune to west nile, allowing the disease to spread.  The result, I suppose, of failed flock immunity.
Imagine how war, human migration, starvation will interact with climate change to increase or alter the spread of malaria, Tb and some infection that no one can predict.  If H1N1 proved anything, it is whatever new infection will sweep  across the county, it will not be the infection we predict. Who would have thought in 1989 that the next decade would see West Nile virus, never seen the the US, arrive to the continent in a migrating goose and become endemic.
Maybe its just the weather, the season, or the climate.  I think these are a few interesting infectious disease associations that lend credence to climate change.

“Conversation about the weather is the last refuge of the unimaginative.” – Oscar Wilde

I will state my bias up front.  I am convinced by the preponderance of data in favor of man made global warming.  At the most simplistic level, I can’t see how converting humongous tons of fossil fuel into CO2 and dumping it into the the atmosphere cannot have effects on the climate.  To my mind its like determining vaccine efficacy or evolution.  Plausible mechanism(s), good basic science, multiple studies using different lines of evidence that all come to the same conclusion.  There are lots of fine points and nuances to be worked out, but the basic truth is reasonable and well defined. Infectious diseases lend some validation to the concept that the world is warming, since with global warming comes a variety of infectious diseases.

It is one big IF:THEN statement.  IF global warming, THEN infections.  Of course  if the IF is not true, then the THEN doesn’t follow.


Posted in: Public Health, Science and Medicine

Leave a Comment (114) →

Homeopathy Gets a Reality Check in the UK

The House of Commons Science and Technology Committee (STC) has released a report, Evidence Check 2: Homeopathy, in which they recommend that the NHS stop funding homeopathy. The report is a rare commodity – a thoroughly science-based political document.

The committee went beyond simply stating that homeopathy does not work, and revealed impressive insight into the ethical, practical, and scientific problems caused by NHS support for an implausible and ineffective pseudoscience.

The STC formed in October of 2009, and this is their second report. The goals of the STC itself are significant step forward:

The purpose of Evidence Check is to examine how the Government uses evidence to formulate and review its policies.

We certainly can use more of that.


Posted in: Homeopathy, Politics and Regulation, Science and Medicine

Leave a Comment (28) →

Chronic Fatigue Syndrome and Retroviruses: Jumping the Gun

When I first heard that a retrovirus had been identified as a possible cause of chronic fatigue syndrome, I withheld judgment and awaited further developments. When I heard that two subsequent studies had failed to replicate the findings of the first, I assumed that the first had been a false alarm and would be disregarded. Not so.

 It’s a classic case of wishful thinking outweighing good judgment. One unconfirmed report of an association between the XMRV virus and chronic fatigue syndrome (CFS) resulted in a rush to test for the virus, speculation about possible implications, and even suggestions for treatment. And the subsequent negative studies did little or nothing to reverse the trend. 

XMRV is Xenotropic murine leukemia virus-related virus. In the past, there were reports that this retrovirus was associated with prostate cancer, but then other reports found no link. In 2009 a study was published in Science, “Detection of an Infectious Retrovirus, XMRV, in Blood Cells of Patients with Chronic Fatigue Syndrome” by Lombardi et al., reporting an association with CFS:

we identified DNA from a human gammaretrovirus, xenotropic murine leukemia virus–related virus (XMRV), in 68 of 101 patients (67%) as compared to 8 of 218 (3.7%) healthy controls. (more…)

Posted in: Basic Science, Science and Medicine

Leave a Comment (41) →

Autism Onset and the Vaccine Schedule – Revisited

This week on Science-Based Medicine I wrote an article about a new study looking at the onset of autism symptoms, showing that most children who will later be diagnosed with autism will show clear signs of autism at 12 months of age, but not 6 months. This is an interesting study that sheds light on the natural course of autism. I also discussed the implications of this study for the claim that autism is caused by vaccines.

Unfortunately, I made a statement that is simply wrong. I wrote:

Many children are diagnosed between the age of 2 and 3, during the height of the childhood vaccine schedule.

First, this was a vague statement – not quantitative, and was sloppily written, giving a different impression from the one I intended. I make these kinds of errors from time to time – that is one of the perils of daily blogging about technical topics, and posting blogs without editorial or peer-review. Most blog readers understand this, and typically I will simply clarify my prose or correct mistakes when they are pointed out.

However, since I often write about topics that interest dedicated ideologues who seek to sow anti-science and confusion, sometimes these errors open the door for the flame warriors. That is what happened in this case.


Posted in: Science and Medicine, Vaccines

Leave a Comment (57) →

Longing for a past that never existed

There once was a time when all food was organic and no pesticides were used. Health problems were treated with folk wisdom and natural remedies. There was no obesity, and people got lots of exercise. And in that time gone by, the average life expectancy was … 35!

That’s right. For most of human existence, according to fossil and anthropological data, the average human life expectancy was 35 years. As recently as 1900, American average life expectancy was only 48. Today, advocates of alternative health bemoan the current state of American health, the increasing numbers of obese people, the lack of exercise, the use of medications, the medicalization of childbirth. Yet life expectancy has never been longer, currently 77.7 years in the US.

Advocates of alternative health have a romanticized and completely unrealistic notion of purported benefits of a “natural” lifestyle. Far from being a paradise, it was hell. The difference between an average lifespan of 48 and one of 77.7 can be accounted for by modern medicine and increased agricultural production brought about by industrial farming methods (including pesticides). Nothing fundamental has changed about human beings. They are still prey to the same illnesses and accidents, but now they can be effectively treated. Indeed, some diseases can be completely prevented by vaccination.

So why are advocates of alternative health complaining? They are complaining because they long for an imagined past that literally never existed. In that sense, alternative health represents a form of fundamentalism. Obviously, fundamentalism is about religion and the analogy can only go so far, but there are several important characteristics of religious fundamentalism that are shared by alternative health advocacy. These include:

Posted in: Science and Medicine

Leave a Comment (494) →

The Early Course of Autism

Understanding the natural history of a disease is an important framework to have. It not only is critical for prognosis, but also informs us about diagnostic and screening strategies, is important to assessing interventions, and provides clues to causation.

There has been much debate about the early course of autism, specifically the earliest age at which autism may be detected. At present scientific evidence suggests that autism is dominantly genetic, and so researchers expect that there may be early signs of autism even in infancy. Traditionally, however, autism is not diagnosed until age 2-3, when parents bring their children to medical attention, or when signs are detected on routine well-child visits or in day-care.

Retrospective studies, largely involving review of home movies, have suggested that autism can be diagnosed as early as 6-12 months, suggesting that parental report is not an adequate screen because subtle signs are hard to detect without rigorous observation.


Posted in: Science and Medicine

Leave a Comment (44) →

Changing Your Mind

Why is my mind so clean and pure?  Because I am always changing it.
In medical school the old saying is that half of everything you learn will not be true in 10 years, the problem being they do not tell which half.
In medicine, the approach is, one hopes, that data leads to an opinion.  You have to be careful not to let opinion guide how you evaluate the data.  It is difficult to do, and I tell myself that my ego is not invested my interpretation of the data. I am not wrong, I am giving the best interpretation I can at the time. For years  I yammered on about how it made no sense to give a beta-lactam and a quinolone for sepsis until a retrospective study suggested benefit of the combination.  Bummer. Now when I talk to the housestaff about sepsis, I have to add a caveat about combination therapy.  It is why my motto is, only half jokingly,  “Frequently in error, never in doubt”.
At what point do you start to change you mind?  Alter your message as a teacher?  Have new behavior?  Medicine is not all or nothing, black and white.  Changes are incremental, and opinions change slowly, especially if results of a new study contradict commonly held conclusions from prior investigations.
Nevertheless, I am in the process of changing my mind, and it hurts.  I feel like Mr. Gumby. ( v=IIlKiRPSNGA)
It is rare that there is one study that changes everything; medicine is not an Apple product.  Occasionally that there is a landmark  study that alters practice in such a dramatic way that there is a before and after.  As I write this I cannot think of a recent example in infectious diseases, but I am sure there is one.  The problem is that once practice changes, it seems as we have always done it that way.
For me, three is the magic number.  One study that goes against received wisdom warrants an ‘interesting, but give me more.”
Two studies, especially if using different methodologies with the same results gives and ‘well, two is interesting, but I can argue against it.”  However, with two studies the seed of doubt is planted, waiting to be watered with the water of further confirmation.  Yeah. Bad metaphor.
Three studies with different methodologies independently confirming new concepts?  Then I say, “I change my mind. My brain hurts.”
There are now three studies concerning the issue of efficacy of the flu vaccine in the elderly.  You might remember my discussion of the Atlantic article several months ago. In that entry I discussed two articles  that suggested the flu vaccine may be less effective in the elderly than the studies demonstrated.
The argument was that the elderly who received the influenza vaccine were healthier at baseline than those that didn’t receive the vaccine and the deaths during flu season was not due to the protection from the vaccine, but due to the fact that healthier people are less likely to die when they get ill. In part this was demonstrated by showing decreased deaths in vaccinated populations when influenza was not circulating.  If insomnia is a problem, you can go back and read my post.   To quote my favorite author, me, I said
“One, it is an outlier, and outliers need confirmation. The preponderance of all the literature suggests that influenza vaccine prevents disease and death. If you do not get flu, you cannot die from flu or flu related illnesses. When outliers are published, people read them, think, “huh, that’s interesting”, but there is going to have to be more than one contradictory study to change my practice. But if “study after study” shows mortality benefit, and one study does not, it is food for thought, but not necessarily the basis of changing practice. The results, above all, needs to be repeated by others… In medicine we tend to be conservative about changing practice unless there is a preponderance of data to suggest a change is reasonable. Except, of course, if our big pharma overlords take us to a good streak house.”
Now we have a third article, “Evidence of Bias in Studies of Influenza Vaccine Effectiveness in Elderly Patients” from the Journal of Infectious Diseases.
In the study they examined the records of the elderly in the Kaiser Health System, their vaccination records, and their risk of death.  And the results were interesting.
“The percentage of the population that was vaccinated varied with age. After age 65, influenza vaccination increased until age 78 in women and age 81 in men, then decreased with increasing age. Vaccination coverage also varied in a curvilinear fashion with risk score, increasing with risk score to a risk score percentile of ∼80%, then decreasing. In addition, as the predicted probability of death increased, vaccination coverage increased. Vaccination coverage was highest among members with a probability of death of 3%–7.5%. Those with a predicted probability of death in the coming year of 17.5% had a de- creasing likelihood of influenza vaccination”
They then looked at mortality when flu was not circulating.
“A change in the pattern of vaccination had a striking effect on mortality. For members > 75 years old who had been receiving influenza vaccinations in previous years, not receiving a seasonal influenza vaccination was strongly associated with mortality in the months ahead (Table 1). A person who had received an influenza vaccination every year in the previous 5 years had a more than double probability of death outside the influenza season if he or she missed a vaccination in the current year, compared with a person who was vaccinated as usual (odds ratio, 2.17; P < .001). On the other hand, if a person did not receive any seasonal influenza vaccination in the previous 5 years, then receipt of a vaccination in the current year was associated with a greater probability of death. “
If they had a history of flu vaccine for five years and missed it, the probability of death went up.
If they did not have a flu vaccine for five years and got one, the probability of death went up.
They suggest in the first case, the patients may have had an increase in their co-morbidities and as a result did not get the vaccine and died of underlying diseases. Their increased risk of death was from accumulating prior illnesses.
In the second case, people who were healthy and did not seek care subsequently developed diseases that lead them to a doctor who advised the vaccine.  Their increase risk of death was due to new illnesses.
Either way, the uptake of the flu vaccine is more complicated than I had suspected and makes interpretation of efficacy of the vaccine in prior studies harder to evaluate.  The table shows an unexpected relationship between age, risk of death and use of the flu vaccine.
table here
They say in the discussion
“We showed that, despite strong efforts to increase vaccination among the elderly population, vaccination is relatively low in the oldest and sickest portions of the population. Persons 65 years old with a 17.5% chance of death in the upcoming year are less likely to receive the influenza vaccine. Because persons who are most likely to die are less likely to receive the vaccine, vaccination appears to be associated with a much lower chance of dying; thus, the “effectiveness” of the vaccine is in great part due to the selection of healthier individuals for vaccination, rather than due to true effectiveness of the vaccine. Previous studies have argued that worsening health is associated with increasing vaccination. We found this to be a curvilinear relationship, in which increasing illness means increasing vaccination, up to a point, and then, as people come closer to the end of life, there is a decrease in vaccination coverage.”
They do not say the vaccine is not effective, but they suggest that there is a bias that may make the vaccine appear more effective in the elderly than it really is.  Reality is often more complex than one would think at the beginning.
After three studies I am reasonably convinced that efficacy of the flu vaccine in the elderly is potentially not as well understood as I had thought.
So do I think the flu vaccine is no longer useful in the elderly?  No.  I still think it is a reasonable intervention but it may not have the efficacy I would like.  But I have always known that, for a variety of reasons, the flu vaccine is not a great vaccine. But it is better than no vaccine. There are, as discussed in the earlier post on the vaccine, many lines of evidence to show that the flu vaccine has benefit; at issue is the degree of the benefit.  Perhaps what is needed is a better vaccine with adjuvants or multiple injections to get a better result in the elderly, who respond poorly to the vaccine.  Or perhaps it will be better to focus on increasing vaccination in those who care for or have contact with the elderly.  But when I talk to my patients and residents, when I get to part about flu vaccine efficacy, I will be a little more nuanced, use more qualifiers. I will tell them that the vaccine is like seat belts.  It does not prevent all death and injury, but if you had a choice, would you not choose to use seat belts?
In the end the data has to change the way I think about medicine, not matter how much it hurts.
Compare and contrast that with the anti-vaxers who have the belief that vaccines cause autism.  They look for data to support the pre-existing belief and ignore contrary data.  Opinion does not follow from data.
The most representative statement of their approach is on the 14 studies website where they say  ““We gave this study our highest score because it appears to actually show that MMR contributes to higher autism rates.”
The key phrase in the whole site. Data that supports their position is good, data that does not is bad. What makes a study good is not its methodology or its rigor, or its reproducibility, or its biologic plausibility,  but if it supports vaccines casing autism.
Dr. Wakefield, as has been noted over the last week, had his MMR/autism paper withdrawn from Lancet not for bad science, but for dishonest science.  In medicine you can be wrong, but you cannot lie.  If the results of medical papers were shown to be fabrications, such as the papers of Scott S. Reuben, no one the medical field would defend the results.  Dr. Reuben, as you may remember, was found to have fabricated multiple studies on the treatment of pain.  Nowhere can I find web sites defending his faked research.  No suggestions it was due to a conspiracy of big pharma to hide the truth. No assertions that he is still a physician of great renown.   He lied and is consigned to ignominy.   Physicians who used his papers as a basis of practice no longer do so, or so I would hope.
The response to Dr. Reuban is in striking contrast to the defense of Dr Wakefield, where bad research combined with unethical behavior, results in reactions like this
“It is our most sincere belief that Dr. Wakefield and parents of children with autism around the world are being subjected to a remarkable media campaign engineered by vaccine manufacturers reporting on the retraction of a paper published in The Lancet in 1998 by Dr. Wakefield and his colleagues.
The retraction from The Lancet was a response to a ruling from England’s General Medical Council, a kangaroo court where public health officials in the pocket of vaccine makers served as judge and jury. Dr. Wakefield strenuously denies all the findings of the GMC and plans a vigorous appeal.”
Opinions did not change when the Wakefield paper was demonstrated to be not just wrong but false, the researcher’s behavior unethical, and the study could not be reproduced using similar methodologies (  Instead, the defense of Dr. Wakefield became, well, like a Jim Carrey shtick. The Mask defends retracted autism research. Fire Marshall Bill on the medical literature.  Jenny and Jim’s defense does make more sense read as comic performance art.  Andy Kaufmann would have been proud.
I wonder if the more grounded in fiction an opinion is, the harder it is to change, the more difficult it is to admit error.  I have to admit I cannot wrap my head around the ability of people to deny reality.  It is the old Groucho line come to life, “Who are you going to believe, science or your lying eyes?”
So I will, I hope, keep changing my mind as new information come in.  It is what separates real health care providers from acupuncturists and homeopaths and naturopaths and anti-vaxers.  It is what some truly great minds admit to doing (  As one deeper thinker and better writer ( than I said, kind of,
“The other terror that scares us from self-trust is our consistency; a reverence for our past act or word, because the eyes of others have no other data for computing our orbit than our past acts, and we are loath to disappoint them.
But why should you keep your head over your shoulder? Why drag about this corpse of your memory, lest you contradict somewhat you have stated in this or that public place? Suppose you should contradict yourself; what then? It seems to be a rule of wisdom never to rely on your memory alone, scarcely even in acts of pure memory, but to bring the past for judgment into the thousand-eyed present, and live ever in a new day. In your metaphysics you have denied personality to the Deity: yet when the devout motions of the soul come, yield to them heart and life, though they should clothe God with shape and color. Leave your theory, as Joseph his coat in the hand of the harlot, and flee.
A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines and anti-vaxers. With consistency a great soul has simply nothing to do. He may as well concern himself with his shadow on the wall. Speak what you think now in hard words, and to-morrow speak what to-morrow thinks in hard words again, though it contradict every thing you said to-day. — ‘Ah, so you shall be sure to be misunderstood.’ — Is it so bad, then, to be misunderstood?”

Why is my mind so clean and pure?  Because I am always changing it.

In medical school the old saying is that half of everything you learn will not be true in 10 years, the problem being they do not tell which half.

In medicine, the approach is, one hopes, that data leads to an opinion.  You have to be careful not to let opinion guide how you evaluate the data.  It is difficult to do, and I tell myself that my ego is not invested my interpretation of the data. I am not wrong, I am giving the best interpretation I can at the time. For years  I yammered on about how it made no sense to give a beta-lactam and a quinolone for sepsis until a retrospective study suggested benefit of the combination.  Bummer. Now when I talk to the housestaff about sepsis, I have to add a caveat about combination therapy.  It is why my motto is, only half jokingly,  “Frequently in error, never in doubt”.

At what point do you start to change you mind?  Alter your message as a teacher?  Have new behavior?  Medicine is not all or nothing, black and white.  Changes are incremental, and opinions change slowly, especially if results of a new study contradict commonly held conclusions from prior investigations.

Nevertheless, I am in the process of changing my mind, and it hurts.  I feel like Mr. Gumby.


Posted in: Clinical Trials, Science and Medicine, Vaccines

Leave a Comment (28) →

CardioFuel—another magic pill

I get a lot of email asking me about various alternative therapies and supplements. A recurring theme on this blog has been the hyperbolic claims of alternative practitioners and supplement makers, and while I can’t answer every email, I can at least address some of them in the blog. Supplements are often marketed using unsupported health claims to which is appended the Quack Miranda Warning, essentially allowing the makers to say that the pill will have such and such a benefit, while simultaneously denying any responsibility for the claim.  Since the FDA isn’t examining these claims, it’s worth while to ask our own questions.

The latest email concerned a product called CardioFuel. Let’s take a closer look at this stuff.

According to the distributor:

CardioFuel is the most profound energy producing supplement on the market today! It does something like no other can: Increase energy at the most basic metabolic level, by increasing ATP (the biochemical energy unit of transfer) production. More ATP means more energy reserves to overcome chronic disease, beat the competition, and handle the everyday stressors of today’s fast paced world!

So to be taken seriously, there should be evidence that this product: 1) increases ATP, 2) increases “energy reserves”, and 3) helps overcome chronic disease and “the competition”. First, it is not possible to directly measure ATP in a human being under normal clinical conditions, so any claims about this must be an inference from markers of ATP metabolism, or a guess. We’ll see what the literature says about this below. Second, we need an operational definition of “energy reserves”. Does this mean fat stores? Glycogen stores? These things are measurable to an extent.  Finally, we can do a literature search to see if CardioFuel or an acceptable analog has been tested for its effect on relevant outcomes.


Posted in: Science and Medicine

Leave a Comment (9) →

Science by press release

Last week I wrote about a study that purported to show that antidepressants have no effect in mild to moderate depression. A careful reading of the paper shows that the authors dramatically overstated their findings, particularly in their public statements to the media. The study has another implication beyond the misleading claims about antidepressants. It is an object lesson in an ongoing and disturbing phenomenon in mainstream journalism, the wholesale reprinting of press releases of scientific papers instead of reading and analyzing the papers themselves.

Pick up any newspaper or magazine and you can read about the latest scientific breakthroughs in cancer, Alzheimer’s or heart disease. Just keep in mind that what you are reading is probably a commercial message direct from the authors, not an accurate representation of the paper itself. Medical journalists are supposed to interpret the findings of recent medical publications and present them to the general public in ways that they can understand. They are supposed to provide context for the discovery, explaining what it might mean for disease treatment or cure. Yet, they rarely do. Instead, they simply copy the press release.

Most people are unaware that scientists issue press releases about their work and they are certainly unaware that medical journalists often copy them word for word. Instead of presenting an accurate representation of medical research, medical journalists have become complicit in transmitting inaccurate or deceptive “puff pieces” designed to hype the supposed discovery and hide any deficiencies in the research.

Imagine if a journalist reviewing the newest Ford cross-over vehicle didn’t bother to drive the car, but simply copied the Ford brochure word for word. Could you rely on the journalist’s evaluation? Of course not. Yet that is precisely what medical journalists are doing each and every day.

Posted in: Science and Medicine, Science and the Media

Leave a Comment (39) →

Checklists and Culture in Medicine

Surgeon and journalist, Atul Gawande, is getting quite a bit of deserved press and blog attention for his new book, The Checklist Manifesto: How to Get Things Right. The premise of his book is simple – checklists are an effective way to reduce error. But behind that simple message are some powerful ideas with significant implications for the culture of medicine.

One of the biggest ideas is that medicine has culture – a way of doing things and thinking about problems that subconsciously pervades the practice of medicine. This idea is not new to Gawande, but he puts it to powerful practice.

The Humble Checklist

Gawande tells not only the story of the checklist but of his personal experience designing and implementing a surgery checklist as part of a WHO project to reduce morbidity and mortality from surgery. He borrowed the idea from other industries, like aviation, that use checklists to operate complex machinery without forgetting to perform each little, but vitally important, step.


Posted in: Science and Medicine, Surgical Procedures

Leave a Comment (9) →
Page 58 of 95 «...3040505657585960...»