Archive for the ‘medical controversy’ Category

Prostate Cancer Controversies

Friday, September 7th, 2012

A prostate cancer awareness symbol

Prostate cancer is the most common cause of cancer death in older men. A few years ago most of us males over the age of forty (it seldom occurs before that) were periodically screened for the disease using the PSA test (a blood test for a prostate-specific antigen) and had digital rectal exams to check the size and consistency of our prostates whenever we had our yearly appointment for a physical and also had comprehensive lab work done.

Then things changed: the annual medical exam was discarded by most physicians in favor of a targeted examination, which in my case, with my history of high blood pressure, includes a nurse taking my BP and my doc listening to my heart and lungs. Not much else, unless I have a specific complaint. I'm 71 and haven't had a digital exam for five years. I had a PSA done when blood was drawn for other reasons and it was 0.7, well under the level that would have raised any concern about my prostate.

In October, 2011, the Harvard Health Blog provided two points of view on pending new recommendations for prostate-specific antigen (PSA) testing from the U.S. Preventive Services Task Force. A panel of experts after a thorough review of the literature on prostate cancer had concluded, that for men over 50, screening using the PSA test offered a low benefit to risk ratio. A huge controversy broke out with the American Urological Association arguing against the proposed new concept. Other physicians noted that an elevated PSA doesn't always mean cancer and, much more importantly, doesn't  distinguish which cancers of the gland are likely to be fast-growing and life threatening.

Oncologist, Dr. Marc Garnick, editor of Harvard's "Annual Report on Prostate Diseases," noted that the new testing recommendation was not a blanket statement fitting all men: those at higher risk (African-Americans and men with family history of cancer of the prostate) may still be suitable candidates for annual PSA testing. He later published an article in Scientific American mentioning that the use of regular PSA testing had led to over a million men having treatment for prostate cancer since 1985 and many thousands of men having complications of prostate surgery or radiation therapy (impotence, incontinence, rectal bleeding).

Dr. Garnick basically agreed with the task force's conclusions; felt the evidence supporting regular PSA testing was flimsy, but thought that the procedure gave important information after a cancer of the gland has been diagnosed.

Garnick was interviewed by a senior editor of the magazine and the resultant February 8, 2012, piece supplies audio comments from Dr. Garnick which detail some of the issues. One such concerns a man who has had his malignancy removed by a total (radical) prostatectomy. His PSA should plummet down to undetectable levels and, if it doesn't, either not all the cancer was excised or there has been spread beyond the local area (metastases).

I was reading my email a few days ago and noted one from my friend Rick with a link leading to an article from the Fred Hutchinson Cancer Research Center in Seattle titled "Prostate Cancer: 6 things men should know." There were six myths rebutted and I especially noted four conclusions: eating tomato-based foods and products doesn't prevent the malignancy; high testosterone levels don't correlate with risk of this tumor; omega-3s don't lower the risk (actually very high blood levels in one study were associated with higher risk); dietary supplements (selenium and vitamin E) don't prevent the disease.

At age 50 and above, this was on my schedule; at age 71 it's not

Another online publication from the Hutchinson Center gives background information on prostatic cancer. They note the frequency of the disease increases in men over 55, that obese men have a higher risk of developing an aggressive form of the disease, as do smokers. Those who drink red wine (four 4-ounce glasses a week) were noted to have a 60% lower incidence. Older men may receive unnecessary surgery; in this group the malignancy, often small and slow-growing, may not be life-shortening.

The need for screening in the general population of men is an ongoing medical controversy. We'll likely hear much more about PSA testing, but many would concede that a new type of evaluation needs to be developed.

I agree and for now I don't plan to have any more PSAs drawn.

 

 

 

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Posted in BPH, digital rectal exam, medical controversy, prostatic cancer, PSA, Scientific American magazine | No Comments »

Biological warfare and Bioterrorism part two: anthrax

Friday, July 6th, 2012

Don't ever open one of these sacks, unless it's your job and you're in full protective gear

I'm reading a book called Germs: Biological Weapons and America's Secret War. It was written in 2001 by three Pulitzer-prize-winning senior newspaper reporters and starts with an event most of us never heard about; immediately after the horrific 9-11 attack: a trained New York National Guard team was sent to NYC to determine if there had also been an accompanying germ warfare attack.

There's a difference between biological warfare and bioterrorism; in one sense it's a matter of scale. In another it's a matter of purpose. In biological warfare the intent is to kill or incapacitate an enemy force. Actually, utilizing the latter approach is likely to be more effective, as it ties up large numbers of support personnel, moving the sick and taking care of them in medical facilities.

Bioterrorism attacks may injure or kill a much smaller absolute number of victims, but, as the term suggests, can spread terror through a huge population base.

So why concentrate on anthrax?

Sheep can get anthrax

Anthrax has a long history in North America, likely arriving thousands of years ago via the Bering Land Bridge. It's been a rare cause of death in the US: most cases here involved mill employees working with wool, farmhands, those who work in tanneries and, potentially, veterinarians. Anthrax was known as a disease of hoofed animals and people caught it from infected beasts. The usual form was cutaneous with a sore like a bug bite that could eventually turn into a black, usually painless skin ulcer. If unrecognized and untreated, the bacteria could spread to the blood (sepsis) with a 20% chance of death; less than 1% died if treated.

Most sources say anthrax spread from person to person never occurs; a few mention rare transmission of the cutaneous form.

But there are two other forms of the disease: the gastrointestinal kind occurs when a person consumes meat from an infected animal. It's been quite rare in the US with one case in 1942 and a second in 2010, but is also quite deadly with a death rate estimated variously at 25 to 60% worldwide and the effects of post-exposure treatment unclear.

And then there is inhalational anthrax, caused when someone breathes in anthrax spores, the dormant phase that can live in soil for many years. When this form occurs, the death rate, which used to be over 90%, even with early recognition and the best possible care, is now estimated at 45%.

The last case of inhalational anthrax occurring naturally in the US was in 1976.

So why did our military gear up to immunize 2.4 million soldiers and reservists in December 1997? After all, President Nixon, in November, 1969, had announced that our country  would totally abandon the use of lethal biological weapons and confine its research in the area to defensive measures. In 1972 the US, the Soviet Union and over a hundred other countries signed the Biological and Toxin Weapons Convention, banning the use of BW.

But many of our own scientists thought this was a mistake. They were proven correct when the anthrax epidemic at Sverdlovsk occurred only seven years later.

The military anthrax vaccination program has a fairly simplistic website, designed to walk young troops through carefully selected and presented facts about the anthrax vaccine. The vaccine has been available since the 1940s and 1950s and was tested in mill workers in the late 1950s. The modern version was licensed in the United States in 1970, and in January, 2002, the FDA allowed the company making it to begin routine distribution from a newer manufacturing plant. The same company is working on a new recombinant version

An October, 2011, Washington Post article discusses the thorny issue of testing the effectiveness of the immunization in children.

Even the safest vaccines have some side effects; the vaccine may not protect versus inhalational anthrax caused by  altered strains of the bacterium and there's no generalized threat at present.

But, what if?

 

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Posted in anthrax, anthrax vaccine, biological warfare, bioterrorism, cutaneous anthrax, gastrointestinal anthrax, inhalational anthrax, medical controversy | 1 Comment »

Mutating the deadly H5N1 flu virus

Saturday, May 5th, 2012

This ferret is healthy

There's been a recent controversy as to whether potentially dangerous medical information should be made available to the public. Now it's happened and I'm somewhat less concerned than I was a few weeks ago. The online version of Nature just published the work of the University of Wisconsin group on making the Highly Pathogenic Avian Influenza (HPAI) type A H5N1 virus transmissible from mammal to mammal, in this case ferrets.

This is potentially a terrible disease; it's killed 355 of the 602 humans (~59%) known to have contracted the HPAI A(H5N1) virus to date. None of those cases involved human to human spread of the flu bug involved. But that's roughly 600 times as lethal as an "ordinary" flu pandemic and more than 20 times as deadly as the 1918 flu.

So why am I less worried than I was?

When I read the article in Nature in detail (and it's tough slogging even for a physician), I realized that the virus, in the process of making it capable of airborne transmission, had also been made less virulent. None of the ferrets used as research subjects died of the disease . The new virus was also found to be preventable by a vaccine and treatable with one of the existing anti-flu medications.

The other thing I quickly understood is this is not a process that the average man (or woman) on the street or even the vast majority of scientists and/or physicians could duplicate. It involved an enormously complex set of laboratory procedures, many of which would demand long-term expertise and experience in the field. Theoretically a virology lab could be influenced by links to a terrorist group or have their own "ultra-green" agenda; neither possibility sounds at all likely to me.

The other paper, detailing the work done on HPAI A(H5N1) in Rotterdam, is yet to be published. That one has me more concerned, but I've just read a paper "Dangerous for ferrets: lethal for humans?" that carefully explores the question involved.

The authors reminded us that a previous paper had discussed the recreation of the so-called Spanish flu virus that killed 50 million worldwide in 1918. I'll write about that in detail some other time, but when that publication appeared, its authors were hailed as heroes, not as dolts.

The work of Ron Fouchier, a senior figure at the Erasmus Medical Center in Holland took the virology world by storm. He first announced his group's alteration of H5N1 at an international meeting in Malta in September, 2011. Initially his variant of the flu virus was thought to be much more deadly to ferrets than the UW bug. A May 3, 2012 paper in Time Healthland discusses the infighting among scientists that followed, but notes that Fouchier's paper should be out in the magazine Science in the near future.

Apparently Fouchier's mutated virus also turned out to be less of a ferret-killer than was initially thought.

There's the normal flu season and the other kind

But that's not the major issue here. Most of those working in the virology field feel a natural mutation of H5N1 or H1N1 or other flu strains is more to be feared than anything produced in a lab. Yet the relatively benign 1977 H1N1 flu pandemic, so-called Russian flu, may have escaped from deep freeze in a lab.

Every year has its flu season; some are much worse than others.

 

 

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Posted in "bird" flu, 1918 flu pandemic, bioterrorism, HPAI A(H5N1), medical controversy, medical research, medically-oriented background info, pandemics, virology | No Comments »

Tick-borne Disease part four: the chronic Lyme Disease controversy

Monday, April 30th, 2012

Sometimes you need an expert panel to resolve a controversy

A March 27, 2012, Wall Street Journal article, "This Season's Ticking Bomb,"predicted that the unusually warm weather most of the country has been experiencing meant we would also see many more cases of tick-borne diseases, If you click on the link, be sure to look at the section called "View Interactive" to get to a series of suggestions on reducing your family's risk of tick bites.

The article itself talked mainly about Lyme disease. There is an International Lyme and Associated Diseases Society (ILADS), but much of their Lyme disease website information was from 2006.  They are on one side of a major medical controversy, how to care for patients who have had Lyme disease and continue to have problems, especially with short-term memory, fatigue, or musculoskeletal issues, well after they have been appropriately treated with short-term antibiotics.

Two articles were published on this subject in 2007-8: the first one, "Chronic Lyme Disease: an appraisal"  is available online; the other, "A Critical Appraisal of Chronic Lyme Disease," appeared in the New England Journal of Medicine.

The real question is whether the bacteria involved, Borrelia burgdorferi, remains in the body of a patient after relatively short-term antibiotic therapy and if a considerably longer course of drug treatment is warranted. The ILADS says, "Yes" to both questions and refers back to a Harvard & Tufts study published in the Annals of Internal Medicine in 1994.

The most recent CDC online information states that 10 to 20% of those who receive standard therapy for Lyme disease will have some lingering symptoms. However they term this "Post-treatment Lyme disease Syndrome." I found that European cases of Lyme and similar diseases are usually caused by our Borrelia borgdorferi's cousins; data from that literature may not be relevant here.

In November 2006, the Attorney General of Connecticut (CAG) pushed the Infectious Disease Society of America (IDSA) into a detailed review of their Lyme Disease guidelines by starting an investigation to decide if they had violated existing antitrust laws. By April 2008, the IDSA and the CAG agreed to end the probe by convening a review panel, with members from Duke, the NIH, Dartmouth, the U.S. Navy, Baylor, Tulane and other centers, to decide if the original guidelines had been based on sound medical/scientific evidence and if they needed changes. An MD, PhD medical ethicist screened panel members for any conflict of interest. A public hearing was held to include other viewpoints. The Final Report of the Review Panel was published in April, 2010.

Some will think the decision ties their doc's hands.

It basically upheld the 2006 IDSA guidelines, but added 1). In some cases (non-pregnant adults or kids 8 or older who've had a tick of the Lyme-carrying species attached for 36+ hours in an area with high infectivity rate of ticks with B. burgdorferi), a single dose of doxycycline (if they have no allergy to this drug) may be given  if the tick was removed within 72 hours; 2). Antibiotics are appropriate for adults and children 8 or older with early, uncomplicated Lyme disease; 3).  "Reports purporting to show the persistence of viable B. burgdorferi organisms after treatment with recommended regimens for Lyme disease have not been conclusive or corroborated by controlled studies." and 4). "The risk/benefit ratio from prolonged antibiotic therapy strongly discourages prolonged antibiotic courses for Lyme disease.

And at the end of the report, they mentioned a disease I'd never heard of; I'll do some more reading and write about it later.

 

 

 

 

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Posted in Annals of Internal Medicine, CDC, Lyme Disease, medical controversy, medically-oriented background info, New England Journal of Medicine, tickborne dieases | No Comments »

Medical Waste: Part two

Sunday, April 15th, 2012

this ECG is normal

In my last post, about trying to decrease the incredible expense of US health care, I gave a link to the ideas Dr. Donald Berwick had outlined in the April 11th edition of JAMA. He thinks we could save huge amounts in six areas: failure of care delivery; failure of care coordination; overtreatment; administrative complexity; pricing failures and fraud & abuse.

Now I'd like to look at a few specific examples.

The same JAMA edition had a research article titled "Association of Major and Minor ECG Abnormalities with Coronary Heart Disease Events" It detailed the followup of nearly 2,200 people in my age range and up (they were 70 to 79) who were in the Health, Aging and Body Composition Study. Thirteen percent had electrocardiograms with minor changes when the study started; twenty-three percent had more significant changes. Both kinds of ECG changes were associated with an increased likelihood of having coronary artery disease (CHD) during the subsequent years.

Now ECGs are relatively cheap and can be done in many settings. But the senior author, Dr. Reto Auer, said in an interview for a publication called heartwire "Our data do not permit one to say anything about clinical practice." The article itself concluded, "Whether ECG should be incorporated in routine screening of older adults should be evaluated in randomized, controlled trials."

In the same edition of JAMA a Northwestern University Preventive Medicine professor, Dr. Philip Greenland, commenting on Auer's research, mentioned a 1989 summary of the value of the "resting ECG," which said additional study was needed. Dr.Greenland said the major finding in Auer's work was a relatively new measurement called the net reclassification index (NRI). As opposed to diagnostic studies (e.g., does this patient have heart disease), this study hoped to be prognostic, telling what the chances were of a major heart event occurring in the future to a particular study subject. In this case the NRI helped most in reclassifying people into a lower CHD risk group, not a higher one.

All of that is fascinating and the Auer article is a superb example of carefully performed research. But, my fear is that many physicians won't read the caveats. If you ignore the last paragraph, skip the editorial and never get to "theheart.org's" take on the work, you may well decide that every older adult should have an ECG done on a regular basis.

What should we do if your cholesterol is high?

In the same edition of the journal is a pair of short articles deliberately set up to examine a medical controversy, in this case whether a middle-aged man with an elevated cholesterol, but no personal or family history of coronary heart disease should be given statin drugs to lower his cholesterol. This is a new feature of the journal, and the accompanying editorial, with the intriguing title, "The Debut of Dueling Viewpoints," explains this will be a continuing series of discussions and debates.

What a wonderful idea.

 

 

 

 

The the online publication, theheart.org actually had a nice summary of the two pieces,

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Posted in coronary artery disease, coronary heart disease, Donald Berwick, dueling viewpoints, medical controversy, medically-oriented background info, statin therapy | No Comments »