A new study published in JAMA sheds further light on a controversial question – whether or not to prescribe low-dose aspirin (81-100mg) for the primary prevention of vascular disease (strokes and heart attacks).
Primary prevention means preventing a negative medical outcome prior to the onset of disease, in this case preventing the first heart attack or stroke. Secondary prevention refers to treatments given to patients who have already had their first heart attack or stroke in order to reduce the risk of subsequent events.
The evidence strongly supports the efficacy of aspirin for the secondary prevention of both heart attacks and strokes. Aspirin has two effects which likely contribute to this protective effect. First, aspirin is an anti-platelet agent – it reduces the stickiness of platelets, which are cell fragments in the blood that clump together to stop bleeding. They can also clump together around an ulcerated cholesterol plaque on an artery, forming a thrombus, resulting in blockage or embolus (the clot traveling downstream) and causing either a heart attack or stroke.
Other anti-platelet agents, such as clopidogrel, are also effective in preventing stroke and heart attack.
Of course, platelets exist for a reason, and blocking their action increases the risk of bleeding or can make bleeding worse when it occurs. Therefore determining the optimal dose and target population are important to maximize the benefit of aspirin or other anti-platelet agent while minimizing the bleeding risk. (more…)
Case reports are perhaps the weakest form of medical evidence. They are essentially well-documented anecdotes. They do serve a useful purpose, however. They can illuminate possible correlations, the natural course of illness and treatment, and serve as cautionary tales regarding possible mistakes, risks and complications. I say “possible” because they are useful mainly for generating hypotheses and not testing or confirming hypotheses.
Dramatic case reports, however, with objective outcomes, like death, can be very useful by themselves in pointing out a potential risk that should be avoided. For example, case reports of objective and severe adverse outcomes are often used as sufficient evidence for pulling approved drugs off the market, or at least adding black box warnings.
The chiropractic community, it seems, does not respond in a similar way to dramatic adverse events that suggest possible risk from chiropractic manipulation. A recent and unfortunate case raises once again the specter of stroke following chiropractic neck manipulation. Jeremy Youngblood was 30 years old, completely healthy, and saw his chiropractic for some neck pain. According to news reports, Jeremy suffered a stroke in his chiropractor’s office while being treated with neck manipulation for the neck pain. According to reports the chiropractor did not call 911, but instead called Jeremy’s father who had to come and pick him up and then bring him to the ER. Jeremy suffered from a major stroke and later died.
The Courage to Heal, the source of many beliefs about false memory syndrome
It is disheartening that we have to return to pseudosciences that have been debunked decades ago, because they continue to linger despite being eviscerated by scientific scrutiny. Belief systems and myths have incredible cultural inertia, and they are difficult to eradicate completely. That is why belief in astrology, while in the minority, persists.
Professions, however, should be different. A healing profession should be held to a certain minimum standard of care, and that standard should be based upon something real, which means that scientific evidence needs to be brought to bear. Professionals are not excused for persisting in false beliefs that have long been discredited.
The 1980s saw the peak of an idea that was never based on science, the notion that people can suppress memories of traumatic events, and those repressed memories can manifest as seemingly unconnected mental health issues, such as anxiety or eating disorders. The idea was popularized mostly by the book The Courage to Heal (the 20th anniversary edition was published in 2008), in which the authors took the position that clients, especially women, who have any problem should be encouraged to recover memories of abuse, and if such memories can be dredged up, they are real.
One of the most interesting aspects of living through the second half of the 20th century and into the first half of the 21st century is the profound change in access to information. I remember in the 1980s there was a buzz (at least among technophiles and science fiction nerds) about how computers were going to be connected in a worldwide network and it would transform the way we access information and communicate. The reality we are living in now exceeds even the most fevered predictions being made at that time.
What was difficult to anticipate was how rapid access to almost any information would affect our day-to-day lives. Now, during a discussion, if a fact is in dispute we can simply look it up and resolve the dispute. I can no longer imagine doing research in a pre-internet age, promoting science-based medicine without social media, or collaborating without the virtual-time communication of e-mail.
The internet is rapidly becoming humanity’s collective culture and body of knowledge. For that reason it is important to nurture that body of knowledge to ensure that it is complete, accurate, and fair. That goal is frustrated, however, by the fact that the World Wide Web is not simply being used for scholarly information. It is also a tool to promote ideology and commercial interests. Therefore any efforts to provide scientifically accurate and unbiased information are likely to be swamped by well-funded and highly-motivated misinformation. Search on any medical topic and you will quickly see what I mean.
In the tradition of James Randi, a Chinese doctor who is an outspoken critic of Traditional Chinese Medicine (TCM) has issued a challenge to its proponents. He has put up 50,000 yuan (about $8,000), which has been matched by donors for a total of over 100,000 yuan, to any TCM practitioner who can use pulse diagnosis to determine with accuracy whether females subjects are pregnant.
Ah Bao is the blogging pseudonym of a burn-care doctor at Beijing Jishuitan hospital. He is trained in scientific medicine and has criticized his country for clinging to pre-scientific philosophy-based health care. He calls TCM “fake science” and now wants to demonstrate that the claims of TCM practitioners are without factual basis.
His challenge is a good one because it focuses on a clear criterion. Subjects will either be pregnant or not pregnant, and the TCM practitioner, using only pulse analysis and blinded to the patient themselves, must determine with an 80% accuracy which subjects are pregnant. A TCM practitioner, Zhen Yang, has taken him up on the challenge and they are now working out the details. (more…)
On the home page of Zhu’s Neuro-Acupuncture Center there is a video relaying a testimonial of how scalp acupuncture helped a patient recover from acute stroke. The use of testimonials is very common in the promotion of dubious health treatments. A personal story and endorsement is psychologically more compelling than dry data. Testimonials are completely unreliable, however, and in fact I would argue that they are ethically questionable. I would even go as far as saying that the presence of testimonials is almost a sure sign that the treatment being promoted is not legitimate.
Webpage screenshot (click picture to embiggen)
What I could not find on Zhu’s website were links to published scientific researcher establishing the safety and efficacy of his treatments. You would think if they existed, he would display them prominently.
Acupuncture for stroke is a common claim, contradicting the notion that acupuncture is primarily used for the symptomatic treatment of subjective symptoms. That, in my experience, is part of the promotional strategy for many CAM treatments. They are presented as benign treatments for symptomatic treatment only, so what’s the possible harm. In reality, proponents will claim they can actually treat diseases whenever given the chance.
One common feature of pseudoscience is that proponents of a specific belief tend to exaggerate its scope and implications over time. In the world of physics this can eventually lead to a so-called “theory of everything” – one unifying theory that explains wide-ranging phenomena and displaces many established theories.
In medicine this tendency to exaggerate leads in the direction of the panacea, the miracle cure for everything. Why does this happen?
There are numerous examples. Here is a video of Bruce McBurney trying to sell his Precious Metals Nano Water to investors in the Dragon’s Den. The product is nothing but distilled water with a tiny amount of silver. McBurney claims that this magic water will essentially cure everything, all bacterial and viral infections, and even cancer.
The panacea is also not the sole domain of the lone crank. Straight chiropractors essentially believe that adjusting the spine can cure everything from bed wetting to asthma, and yes, even cancer.
What factors predispose to the panacea claim? (more…)
In April 2013 President Obama announced the BRAIN initiative – Brain Research through Advancing Innovative Neurotechnologies – committing 100 million dollars to brain research. The goal of this initiative is to accomplish with the brain what the Human Genome Project accomplished with the human genome.
The BRAIN project came after a similar, and larger, initiative in Europe – the European Union’s Human Brain Project (HBP), which was given 1.3 billion dollars in funding. The HBP came under some controversy this summer when neuroscientists complained about how the money was being awarded.
The serious commitment to brain research on both sides of the Atlantic reflects the general recognition that the brain is an important and complex organ (arguably the most complex thing we know about in the universe) and there is tremendous opportunity to reap benefits from new research.
The comparison to the Human Genome Project is quite deliberate. The HGP is generally perceived to have been incredibly successful, the biological equivalent of announcing that we will send people to the moon by the end of the decade, then doing it.
It looks like we can file this one under “here we go again.” A small town in Colombia, El Carmen de Bolivar, has seen more than 200 girls hospitalized with a mysterious illness since May of this year. The symptoms include dizziness, headaches, and fainting. So far, all of the girls hospitalized have been found to be healthy and were quickly released from the hospital without discovering any specific disease or pathology.
Unfortunately I have to depend on news outlets to provide information about this case, and most are skimpy on details. However, taking what is being reported, the case has all the features of mass psychogenic illness. Specifically, the cases are clustering in a small community, which is typical for typical for episodes of mass delusions. The symptoms being reported are all subjective and the kinds of symptoms that can result entirely from psychological stress. I have seen no reports of objective clinical findings, such as fever, rash, abnormal laboratory findings, strange lesions, or objective findings on exam.
Doctors who have examined the patient feel that the presentation is consistent with psychogenic illness. I have discussed this at length previously. A psychogenic illness results from the physical manifestation of psychological stress. This is always partly a diagnosis of exclusion, meaning that other causes of the presenting symptoms need to be ruled out. However, it is more than just a diagnosis of exclusion, as there are sometimes clinical features that can be positively demonstrated to be psychological rather than physical. The ultimate test of the psychogenic diagnosis is that patients should improve with support and encouragement.
The Hollywood Reporter recently published what is mostly an exposé on privileged Hollywood parents who have elected to delay, limit, or avoid altogether immunizing their children. The most common headline coming out of this article is that some LA communities have vaccination rates at third-world levels, such as South Sudan. The issues raises many questions pertinent to the promotion of science-based medicine – what leads an otherwise well-educated individual with financial security to make decisions that actually put their own children (and others) at risk?
We have often observed at SBM that the anti-vaccine movement is likely to experience a serious backlash once epidemics of vaccine-preventable diseases start to emerge. I think we are seeing the beginning of this prediction coming true. Vaccines are partly the victim of their own success. The diseases they prevent, such as polio, measles, whooping cough, and others, are now uncommon. Modern parents have the privilege of not fearing these diseases because the vaccination program has reduced them to sporadic cases. Therefore, when pseudoscientists or ideologues stoke fears against vaccines, the fear of the diseases they prevent is not there as a balancing force.
That may be changing, however. The CDC reports:
During 2012, 48,277 cases of pertussis were reported to CDC, including 20 pertussis-related deaths. This was the most reported cases since 1955. The majority of deaths occurred among infants younger than 3 months of age.
From January 1-August 16, 2014, 17,325 cases of pertussis have been reported to CDC by 50 states and Washington, D.C.; this represents a 30% increase compared with the same time period in 2013.