August 29, 2011
TED talk: Tim Harford on trial, error and the God complex
April 2, 2011
The continued risk of antibiotic resistance
The Economist has a good piece on the problems with mis-use of antibiotics:
Convenience and laziness top the list of causes of antibiotic resistance. That is because those who misuse these drugs mostly do not pay the cost. Antibiotics work against bacteria, not viruses, yet patients who press their doctors to prescribe them for viral infections such as colds or influenza are seldom harmed by their self-indulgence. Nor are the doctors who write useless prescriptions in order to rid their surgeries of such hypochondriacs. The hypochondriacs can, though, act as breeding grounds for resistant bacteria that may infect others. Even when the drug has been correctly prescribed, those who fail to finish the course are similarly guilty of promoting resistance. In some parts of the world, even prescription is unnecessary. Many antibiotics are bought over the counter, with neither diagnosis nor proper recommendations for use, multiplying still further the number of human reaction vessels from which resistance can emerge.
Nor is the problem confined to people. Analysing official figures, Louise Slaughter, an American congresswoman who is also a microbiologist, calculates that four-fifths of the antibiotics used in America are given to livestock, often to get perfectly healthy animals to grow faster. That is convenient, because it produces cheaper meat, but it creates yet more opportunities for bugs to evolve resistance.
All this matters because antibiotic resistance has both medical and financial costs. It causes longer and more serious illnesses, lengthening people’s stays in hospital and complicating their treatment. Sometimes people die unnecessarily. In one study, which sampled almost 1,400 patients at Cook County hospital in Chicago, researchers found resistant strains of bacteria infecting 188 people, 12 of whom died because they could not be treated adequately. At the moment, resistant bacteria threaten mostly children, the old, cancer patients and the chronically ill (especially those infected with HIV). However, there could be worse to come. Nearly 450,000 new cases of multidrug-resistant tuberculosis are recorded each year; one-third of these people die from the disease. More than a quarter of new cases of TB identified recently in parts of Russia were of this troublesome kind.
February 22, 2011
Iatrogenic hypertension
It’s possible that millions of people are on high blood pressure medication today who don’t really need to be:
Currently, anyone suspected of having high blood pressure is diagnosed by a GP with an inflatable arm cuff. Doctors then call the patient back for additional readings, but these are always taken at their surgery or in hospital.
New draft guidance to be published today by the National Institute for Health and Clinical Excellence (Nice) says as many as one in four people experiences a surging pulse rate on entering a GP’s surgery.
This nervous response, termed “white coat hypertension”, can significantly raise blood pressure readings and many people are being misdiagnosed as a result.
To counter this, Nice is recommending that doctors do not rely solely on readings taken in their own surgeries. After the initial assessment, a patient should be sent home and asked to wear an ambulatory blood pressure monitoring (ABPM) device.
A suspicious mind might wonder if there’s a financial benefit to drug companies large enough to have them pressure physicians to diagnose high blood pressure even in people whose readings are not far off normal.
H/T to Eric Kirkland for the link.
January 7, 2011
How not to handle public health issues like influenza
I was astonished to hear a radio reporter yesterday admit that much of the reason for the drop in people getting flu shots is the massively overblown oh-my-god-we’re-all-going-to-die media panic last year over Swine flu H1N1. In case you somehow managed to miss out on it last year, every news broadcast seemed to feature yet another doctor or public health official telling us that we faced a worldwide pandemic of H1N1 which was the invincible, all-conquering Überflu to top all plagues we’d ever faced before. Death tolls in the millions were confidently predicted. Every individual who died seemed to be mentioned personally . . . because there were so relatively few compared to those poor folks who died of “ordinary” seasonal flu.
Lorne Gunter gives a bit of credit where it’s due:
Give Allison McGeer credit for being frank about what’s behind this winter’s flu outbreak in Ontario: unnecessary panic over last year’s swine flu “pandemic.” Dr. McGeer, head of infection control at Toronto’s Mount Sinai Hospital, says flu cases are way up this season because vaccinations are way down; and vaccinations are way down, likely, because too much was made of the swine flu by media and officialdom last winter.
It is a medical case of the doctors who cried wolf, in other words.
[. . .]
There is a fine line between erring on the side of caution and crying wolf. And last year, the UN’s World Health Organization (WHO) blew through that barrier with abandon.
Just as it had on SARS and bird flu and the Ebola virus, the WHO overreacted to swine flu, issuing cautions that were out of all proportion to the risk the disease posed to the public. (Remember in 2003 when the WHO recommended people from around the world stay away from Toronto because the city was host to a few hundred SARS infections?)
But unlike those earlier panics, the WHO pulled out every stop on swine flu. It was as if the UN agency had been surprised that its earlier scares had failed to grow into full-blown pandemics; and so they figured that, finally, swine flu was due to become a worldwide infection requiring a dramatic response from international health officials.
As I wrote last year in May, when even the most panic-stricken media outlets were no longer playing the JuggernautOfDoom theme:
This would have been a good opportunity for de-escalating the panic mongering (and perhaps even attempting to rein-in the media, who were equally to blame for the tone of the information getting to the public). They chose, instead, to actively hide the fact that H1N1 cases were running below the level of ordinary seasonal flu cases (total H1N1 deaths: approximately 18,000 — typical annual death toll from seasonal flu: 250,000-500,000).
The biggest problem isn’t that they over-reacted this time, it’s that it has reduced their credibility the next time they start issuing health warnings. And that’s a bad thing. Unless they pull the same stunt next time, too. In which case, we may start hearing talk about setting up competing organizations to do the job the current entities appear to have given up on.
December 23, 2010
Aspirin, the rediscovered wonder drug
A recent study intended to verify that small doses of aspirin did reduce the chances of heart attack and stroke has also shown that it reduces the incidence of certain cancers:
In trials lasting between four and eight years, the patients who had been given aspirin were 21% less likely to die from cancer than those who had been given a placebo. These results were based on 674 cancer deaths, so are unlikely to represent the kind of statistical oddity that can beset studies on cancer risks that sometimes create headlines.
The benefits of aspirin were also apparent many years after the trials had ended. After five years, death rates for all cancers fell by 35% and for gastrointestinal cancers by 54%. A long-term follow-up of patients showed that the 20-year risk of cancer death remained 20% lower in those who had taken aspirin.
The study revealed that the effect takes time to accrue, so aspirin must be taken over a long period. The latent period for improving oesophageal, pancreatic, brain and lung cancer was about five years of aspirin taking on a daily basis. For stomach and colorectal cancer the effects took ten years and for prostate cancer about 15 years. The means by which aspirin prevents cancer is not well understood. It is believed that it inhibits an enzyme that promotes cell proliferation in tumours.
August 5, 2010
Examining DNA testing from the client’s point of view
Mary Carmichael is writing a multi-part series about DNA testing:
On July 22, Congress held a hearing on direct-to-consumer (DTC) genetic tests, services that analyze your DNA and interpret the results in exchange for a few hundred bucks — no doctor necessary. The hearing could have been a thoughtful national conversation about science, business, and ethics. Alas, it devolved instead into a series of gotcha moments, starring a General Accounting Office sting operation that came off like a cross between the ACORN videos and the world’s worst ad for snake oil.
Time and again, on tape, an undercover agent called up an unidentified testing company and asked an ill-informed question. (“Is it OK if I stop taking my cholesterol meds and instead take the nutritional supplements you sell? If I can manage to get hold of my fiancé’s saliva without him knowing, will you run it through your machines so I can surprise him with the ‘gift’ of his own data?”) And time and again, the phone rep sank to the occasion and made the company look awful. (Sure, lay off the pills and take our supplements! Of course we’ll analyze your fiancé’s spit without his permission even though that’s illegal, unethical, and weird!)
I listened to the tape several times the day it was released, despairing at the way people were taking advantage of gullible, albeit fictional consumers, which was clearly how the congressmen who held the hearing wanted me to react. Then I started to worry about something else. How much time did I even have left to decide whether I was going to take a test myself? Even before the hearing, the FDA had announced its plans to regulate all DTC genetic tests, possibly so heavily as to keep them off the market; the hearing was just the sort of thing that could push it to move faster. What if, by the time I finally decided if I wanted one of these tests, I couldn’t buy one anymore? My credit card was sitting next to my laptop. I did something that in retrospect seems a bit rash. There’s a DNA-collection kit on my desk now, taunting me — because although I bought the thing, I still can’t decide whether I actually want to use it.
The sheer volume of misinformation on DNA testing — combined with public belief in the amazing accuracy of DNA testing (probably induced by watching too many crime investigation TV shows) — leaves the legitimate companies in an awkward situation. The actual DNA self-tests don’t tell you what you might expect, and can tell you things you don’t want to know. Politicians jumping in now (at the prompting of bureaucrats who want more power to regulate) will only make the situation more confused.
H/T to BoingBoing for the link.
August 4, 2010
Canada’s (lack of) abortion rules
Apparently lots of Canadians think that the country’s laws are far more restrictive of abortion than they really are:
Two-thirds of Canadians do not know that Canada has no abortion law, according to a new poll that indicates Canadians are woefully misinformed about a landmark ruling in the country’s history.
The poll, which asked 1,022 Canadian adults about their understanding of the country’s abortion regulations, found that just 22% of Canadians correctly identified a woman’s right to an abortion with no governmental restrictions. Canada has not had legislated abortion rules since 1988, making the country an “absolute outlier” on the issue, according to a medical ethicist.
“There’s really only a very small number of Canadians that correctly identify the current situation in Canada,” says pollster Jaideep Mukerji, who worked on the Angus-Reid poll, which was released on Tuesday. “That could be problematic.”
This was highlighted over the last couple of months, with the government and opposition wrangling over Stephen Harper’s initiative to increase funding for maternal health in the developing world. Because opinions widely differ over what the law covers in Canada, it was easy for the opposition to portray Harper’s plan as being ideological rather than humanitarian due to the exclusion of abortion.
Canadians don’t want to re-open the debate, although most appear to want more restrictions in place.
May 26, 2010
The pandemic juggernaut of doom . . . that failed to materialize
Lorne Gunter has a good wrap-up of the bone-headed approach of public health officals in Canada to the Swine H1N1 flu “pandemic”:
Good on ordinary Torontonians. Despite all the H1N1/swine flu hype this past winter, just 28.2% of that city’s residents bothered to get vaccinated against the “pandemic;” that’s less than the 35% who usually get shots each year against the seasonal flu.
Even Toronto health care workers couldn’t be stampeded into getting the shots. Only 60% of them bothered.
[. . .]
Even from the start, the World Health Organization and other experts where told this strain of flu was weak and easily defeated. Infection rates never came remotely close to forecasts and death tolls were thankfully much, much lower than for typical seasonal infections.
The trouble, I think, was that so many public health officials have predicted so many pandemics for so long — SARS, bird flu, swine flu — that they simply got caught up in their own warnings and projections. They wouldn’t listen to contrary evidence.
The relevant public health authorities would have served the public interest (and their own credibility for the future) if they’d been much more forthcoming as the early stages of the pandemic showed H1N1 not to be the second coming of the Black Death. Instead, they doubled-down and raised the propaganda bar even higher.
October 27, 2009: Given that regular seasonal flu causes thousands of deaths annually, you’d think it would be good statistical discipline to count the cases of H1N1 separately, both the gauge the severity of the disease and to chart the effectiveness of the vaccination program. Lumping seasonal flu and “flu-like symptoms” together with H1N1 seems a big step backward from normal public health practice.
This would have been a good opportunity for de-escalating the panic mongering (and perhaps even attempting to rein-in the media, who were equally to blame for the tone of the information getting to the public). They chose, instead, to actively hide the fact that H1N1 cases were running below the level of ordinary seasonal flu cases (total H1N1 deaths: approximately 18,000 — typical annual death toll from seasonal flu: 250,000-500,000).
The biggest problem isn’t that they over-reacted this time, it’s that it has reduced their credibility the next time they start issuing health warnings. And that’s a bad thing. Unless they pull the same stunt next time, too. In which case, we may start hearing talk about setting up competing organizations to do the job the current entities appear to have given up on.
April 15, 2010
“Wolf! Wolf! Wolf! Oh, never mind . . .”
Marni Soupcoff points out that the World Health Organization should have been far more forthcoming after their intial “the sky is falling” announcements caused panic last year over H1N1:
Admit your mistakes before others exaggerate them. That’s the oft-quoted wry advice of writer and retired surgeon Dr. Andrew V. Mason. Perhaps the World Health Organization (WHO) was trying to follow it this week by convening a three-day meeting of outside experts to review the organization’s handling of the recent swine flu outbreak. The problem is, despite claiming to want to know what went wrong as much as what went right, the WHO seems unwilling to even entertain the possibility that it created a counterproductive panic by labelling H1N1 a pandemic of the highest order (“level 6”).
Swine flu, as you’ve probably realized by now, has turned out to be a mild, not particularly deadly virus — it’s certainly far less deadly than the regular seasonal flu that most of us consider a mundane part of everyday life. If one were feeling charitable toward the WHO, one could point out that it didn’t know back in the spring of last year — when it shouted “level 6!” from the rooftops — that H1N1 would prove to be such a relatively innocuous bug. But it’s precisely because it didn’t know that the WHO should have been more cautious with its labelling. You don’t shout “fire” in a crowded theatre just because it smells like the popcorn might be a little on the burnt side. It’s not worth the chaos and alarm you might cause. (Or in this case, the run on vaccines and the resorting to quacks and sketchy “home” remedies.)
Between the unrestrained use of the term “pandemic” and the noted ability of the mass media to hype real and imagined risks, it’s almost surprising we didn’t have doomsday-style cults spring up over H1N1.
February 23, 2010
February 2, 2010
The Lancet formally retracts controversial paper on Autism
In a long-overdue move, British medical journal The Lancet has retracted a paper by Andrew Wakefield on links between the MMR vaccine and Autism:
The Lancet medical journal formally retracted a paper on Tuesday that caused a 12-year international battle over links between the three-in-one childhood MMR vaccine and autism.
The paper, published in 1998 and written by British doctor Andrew Wakefield, suggested the combined measles, mumps and rubella (MMR) shot might be linked to autism and bowel disease.
His assertion, since widely discredited, caused one of the biggest medical rows in a generation and led to a steep drop in the number of vaccinations in the United States, Britain and other parts of Europe, prompting a rise in cases of measles.
The knock-on effect of parents avoiding getting their children vaccinated creates opportunities for much more serious outbreaks of these diseases. Dr. Wakefield’s “research” has been harmful to the population at large for helping to create and exacerbate parents’ fears for their children, and in encouraging them to take the greater risk of not getting the MMR (and, in many cases, other vaccinations) for their kids.
January 26, 2010
CF improve medical evacuation by adding medical technicians to crews
Strategy Page reports on a change in crew composition for Canadian Forces medical evacuation helicopters:
Canadian forces have added a medical technician to the crews of their medical evacuation helicopters, joining a trend that has played a part in saving the lives of many troops wounded in combat, or injured in a combat zone. Previously, Canadian troops had relied on American, or other NATO, air evacuation services. But now Canada has suitable helicopters (CH-146s) for that work, and established an air ambulance service. Following a four year old recommendation by their own military planners, Canada trained medical technicians to work on the medevac choppers, and thus increase the chances that badly wounded soldiers would survive. Canada has also upgraded all of its combat medical care during its years of operations in Afghanistan. This is part of a trend that has been going on since World War II. It’s all about having more medical care available sooner.
The fighting in Iraq and Afghanistan has brought about a major change in how the United States deals with combat casualties. The result is that over 90 percent of the troops wounded, survive their wounds. That’s the highest rate in history. There are several reasons for this. The main one is that medics, and the troops themselves, are being trained to deliver more complex, and effective first aid more quickly. Military doctors now talk of the “platinum 10 minutes,” meaning that if you can keep the wounded soldier, especially the ones who are hurt real bad, alive for ten minutes, their chances of survival go way up. Medics have been equipped and trained to perform procedures previously done only by physicians, while troops are trained to do some procedures previously handled only by medics.
November 30, 2009
Doctors urged to advise patients on reducing their carbon butt-print
The Climate and Health Council in Britain is urging GPs to provide their patients with information on how to reduce their carbon output:
The Council has been recently formed to study the health benefits of tackling climate change and promotes a range of ideas from reducing your carbon footprint by driving less and walking more to eating local, less processed food.
It wants to raise ‘health’ on the agenda of December’s UN Climate Change Summit in Copenhagen.
They believe that offering patients advice on how to lower their carbon footprint can be just as easy and achievable as helping them to stop smoking or eat a healthier diet.
Other proposals include for all developed nations to pay an extra five dollars a barrel on oil and a tax on airline tickets. This would go into a special fund to develop low-carbon alternatives to existing technologies, they say.
So, after waiting for however many weeks to get that precious 2.5 minutes of actual patient-doctor interaction, two minutes will now be composed (in a Freudian slip, I originally mistyped that as “composted”) of Climate-Puritan hectoring. That’ll do wonders for both the environment and for doctor/patient relations.
November 11, 2009
The only surprise is that it’d only be 33%
Alison Martin summarizes a survey of Quebec workers which found (among other things) that 33% of men would show up for work even if they or a family member had H1N1:
According to a poll of Quebec workers, many employees in Quebec would still show up for work even if they had the H1N1 flu virus.
Close to one-quarter of respondents to the poll conducted in September 2009 on behalf of the Ordre des conseillers en ressources humaines agréés said that they would still go to work even if they or a member of their household had the H1N1 flu virus. This attitude is even more prevalent among men, with one in three (33%) reporting that they still intended to go to work if they or a relative caught the virus.
Close to 60 per cent of respondents said that they show up for work even when they really aren’t feeling well.
“We’ve already noted that employees in Quebec tend to show up at work even when they’re ill. They don’t seem to be sufficiently aware of the risks of such behaviour, which in the end benefits neither the employee nor the employer, and definitely should be stopped,” explained Florent Francoeur, CHRP, Ordre president and CEO.
The question was clearly worded to elicit the most newsworthy headline: it’d be an odd family if everyone stayed home if even one person in the family was ill . . . and a family with limited long-term employment prospects. Private sector employers tend not to have the same kind of generous sick time provision that public sector employees get, so employees don’t tend to take as much sick time as civil servants.
For many workers, if they don’t show up for work, they don’t get paid. This is especially true at lower income levels, where missing a few days pay can be a severe economic dislocation.
November 3, 2009
“Like Soylent Green, medicine is made of people”
Colby Cosh on the paradoxical nature of the public’s view of medicine:
We’re conditioned to think of “medicine” as a single, coherent planned enterprise, if not a conspiracy, and we often fear and despise it — until we decide we need it. At which point it cannot possibly move fast enough to please us. Like the state or the church, medicine is an impersonal abstraction, but one that seems to have common priorities and intentions, significant powers and one voice. Rationalists and believers in progress invoke it; nutcases and conspiracists resist it.
In a way, both are paying tribute to a fiction, much like Christians and Satanists. In real life, there is no pope or president of medicine, no temple where it can be consulted, no medical mandate of heaven. The emerging vaccine debacle, though mercifully likely to have fairly limited public-health consequences, reveals the terrible truth. Like Soylent Green, medicine is made of people. Not just doctors, but administrators, industrialists, economists and politicians — none of them angels, and none with an angel’s ability to predict mass behaviour, perceive and weigh risk, or foresee the judgment of future history.
[. . .]
People have always been prone to weird beliefs, but now there is a medium that compounds those beliefs, allows them to coalesce into a historical counter-narrative and unites their holders like never before. For the first time, there are people who seem not just weird, but positively, thoroughgoingly “weird-ist.” Try spelunking amidst the Internet detritus of the anti-vaccine movement. There is no philosophical reason that strange beliefs about vaccination should correlate with fringe beliefs about UFOs, reptilian elites, 9/11 “truth,” JFK, the world ending in 2012 you name it. Yet the correlation is real, and not hard to confirm.
