March 16, 2012 | 9:53 am

Epidemiology is Much Worse For You Than Red Meat

Posted by Albert Fuchs, M.D.

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“Red meat is not bad for you. Now blue-green meat, that’s bad for you!”—Tommy Smothers

I generally try to avoid writing about meaningless studies that should be ignored. First, there are a lot of them. Second, I don’t want to attract more attention to them than they already get in the media. But sometimes a meaningless study seems to perfectly confirm what we already wanted to believe. Then a feedback loop of reader gullibility and media misunderstanding leads inevitably to reaching a conclusion entirely unsupported by the science. Then I feel obligated to shine some light on the confusion.

This week’s expedition into folly was occasioned by a study published in the Archives of Internal Medicine which attempted to find a link between eating red meat and mortality. My regular readers know that the only way to test whether some substance has some effect is to do a randomized study. That means if we wanted to know whether eating more red meat caused people to die sooner than eating less red meat we would need to do the following: Recruit a few thousand people with moderate meat intake and get their permission to control their diets. Then randomize them into two groups. One group eats a vegetarian diet, and the second group eats a whole lot of red meat. Follow them all and count deaths. Voila! This would be good science and would teach us a lot about any link between eating red meat and longevity. It would be expensive and logistically difficult, but nature does not yield her secrets easily.

Is this what was done in the study published this week? Not even close. The study looked at data collected in two previous large epidemiologic studies, the Health Professionals Follow-up Study, which started in 1986, and the Nurses’ Health Study which started in 1980. Neither of these studies was randomized. They simply followed large groups of people and assessed their health periodically. There was absolutely no intervention done, just observation. They were given questionnaires every few years about their diet, from which their meat consumption was estimated. Then the deaths among the participants were recorded, and calculations were done to see if there is a correlation between meat ingestion and mortality.

And guess what? There is. The people who ate more red meat had a slightly higher mortality than people who ate less red meat. That means that eating red meat is correlated with increased mortality. It does not mean that eating red meat is what kills people. Meaning, it doesn’t mean that changing your diet changes your risk. The authors of the study, of course, know this and never use words like “cause”, but media coverage that followed completely missed this distinction and waxed hysterically that “all red meat is bad for you”.

Observational studies have almost never steered us towards the truth. Remember that observational studies suggested that estrogen prevents strokes and heart attacks. It took a randomized study to show that it doesn’t. That’s because without randomization you never know if the people that are choosing to eat red meat are different from the people who don’t in some important way that increases their mortality but has nothing to do with the meat. For example, in this study the people who ate more meat were less likely to be physically active, more likely to be current smokers, to drink alcohol, and to be overweight than those who ate less meat. The authors of the study used statistical methods to account for these differences, but there were almost certainly other differences that could not be guessed or accounted for.

Also, an observational study can’t tell us in which direction the causal arrow points. Meaning, if sick people craved more meat, then the link between the two would be due to high mortality causing more meat eating, not the other way around.

So this study teaches us absolutely nothing about a putative link between eating meat and death. It should have been completely ignored by the media, and it doesn’t deserve a moment of your attention.

But let’s take the study’s data at face value and see what all the media hullabaloo is about. The study found that an increase of one serving of unprocessed red meat per day was associated with a 13% increase in mortality, and a 20% increase for processed meat. Let’s take the higher number, 20%, that’s terrible right? That must amount to people dropping dead in droves soon after biting into their hot dogs.

The study followed people for a total of 2,960,00 person-years, during which almost 24,000 deaths were counted, for an average of 0.0080 deaths per person-year. 20% of that is 0.0016 deaths per person year, which is one additional death for 619 person-years.

So let’s pretend that the link between red meat and death is real (which is completely unsupported by this study) and let’s imagine two groups of people. The first group is composed of 100 vegetarians. The second group is 100 people who eat one serving of red meat daily, perhaps the delicious burger in the picture above, which happens to be from Jeff’s Gourmet Kosher Sausage Factory. (The folks at Jeff’s don’t know me and didn’t pay me for this post, but if they were to thank me with one of their beef wraps, that would be just fine.) The group of meat eaters would have one additional death after six years and two months. In that time they would have consumed 225,935 burgers. So 225,935 servings of meat correlate to one additional death.

That makes a burger a lot less dangerous than, say, having general anesthesia, and about as dangerous as driving 300 miles, but much yummier.

So we’ve learned nothing about whether eating more red meat affects longevity, but we’ve learned a lot about what happens when preconceived opinions seem to be confirmed. People attach a lot of weight to arguments which purport to demonstrate what they already think should be true. We feel that red meat should be bad for us. We feel guilty because cows are so cute and meat is so tasty. There must be a health risk to balance the scales and atone for our guilt.

If there is, it will take a well designed randomized study to prove it. Until then, skepticism, and a slice of brisket, is in order.

“Mmmmm… Burger.”—Homer Simpson

Learn more:
All red meat is bad for you, new study says (LA Times)
Risks: More Red Meat, More Mortality (NY Times Vital Signs)
Red Meat Consumption and Mortality (Archives of Internal Medicine)
I calculated the risk of driving from the WolframAlpha calculations for “US auto fatalities per year” and “US auto miles driven per year”

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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March 9, 2012 | 2:24 pm

Clostridium difficile Infections on the Increase

Posted by Albert Fuchs, M.D.

In 2010 I predicted that Clostridium difficile (C. dif.) would become a household name. C. dif. is a bacterium that infects the colon causing severe, sometimes life-threatening, diarrhea. C. dif. infection is frequently a complication of antibiotic use. Antibiotics can kill the normal bacteria in the colon and establish an opportunity for C. dif. to proliferate. After a course of antibiotics, a person can remain susceptible for a few months, and subsequent exposure to C. dif., usually in a healthcare setting, can lead to infection.

This week the Centers for Disease Control and Prevention (CDC) released a report publishing the latest data on the trends in C. dif. infections. These trends are not encouraging.

The number of annual C. dif. infections, and the number of those which are fatal, are higher than ever, with 14,000 estimated annual deaths. Virtually all of them were transmitted in healthcare settings. About a quarter were acquired in hospitals, and most of the rest in nursing homes. Most of the deaths were in patients 65 years and older.

The increased number of infections and deaths is attributed to a more virulent strain that has emerged in the last few years, and on our continued misuse of antibiotics. The CDC estimates that about half of all antibiotics given are unnecessary.

The CDC has some important advice to help stem the tide of C. dif. infections. This epidemic will require attention from patients, physicians, hospital and nursing home administrators, and regional and national health agencies. The challenges to hospitals seem quite daunting. Many patients develop C. dif. infections in nursing homes and are admitted to hospitals without the information about their infection being sent with them. Moreover, hand sanitizers now in universal use in hospitals don’t kill C. dif. spores, so doctors must use gloves and gowns to prevent spreading the infection to other patients.

The CDC recommends that doctors prescribe antibiotics with greater care, diagnose C. dif. more promptly, and assure that patients with C. dif. are appropriately isolated from other patients. Patients should take antibiotics only as prescribed, inform the doctor if diarrhea develops within a few months of an antibiotic course, wash hands carefully after using the bathroom, and if possible use a separate bathroom if they have diarrhea.

Unfortunately, we will continue to hear much more about this germ in coming years.

Learn more:

The Latest on Clostridium Difficile, From the CDC (Wall Street Journal Health Blog)
CDC: Deadly and preventable C. difficile infections at all-time high (CNN Health)
Making Health Care Safer, Stopping C. difficile Infections (CDC Vital Signs)
Preventing Clostridium difficile Infections (CDC Morbidity and Mortality Weekly Report)
A New Treatment for Clostridium difficile (my post about C. dif. In 2010)

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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March 2, 2012 | 2:25 pm

Doctor, Test Me for Everything

Posted by Albert Fuchs, M.D.

“Doctor, I really want to stay healthy and I just got a big promotion/had a baby/had a grandchild, so I really don’t want to end up with some horrible illness. Please test me for everything.”

Primary care doctors hear requests like this all the time. It’s an impossible request to fulfill because it assumes two premises that are usually false. It assumes that we have a test for all illnesses, and that being diagnosed early with a dreaded illness makes a difference.

Monday’s NY Times published a terrific op-ed about the myth of early diagnosis. I highly recommend it. It’s brilliant and short, and the rest of my post will make a lot more sense if you read the op-ed first. Go ahead. I’ll wait.

*****

I hope you found that illuminating, and I assume you also found it counterintuitive. That’s because for over a generation we have seen doctors on TV dramas shake their heads in sorrow and say “If only we had caught it earlier”. We have also been urged to get tested for the very few diseases in which early diagnosis makes a difference. For example high cholesterol and high blood pressure cause no symptoms, but detecting and treating them prevent strokes and heart attacks. So we assume that most other diseases work the same way – catch them early, before they cause symptoms, and you’ll have a better outcome.

But it just isn’t so. We’ve proven that screening for breast cancer and colon cancer saves lives, but for the vast majority of diseases, early diagnosis makes absolutely no difference in outcomes. So if I’m going to get lymphoma or lupus or pernicious anemia or myriad other illnesses, there’s absolutely no reason for me to do a thing about it until I feel sick. Even writing this feels sacrilegious because we are constantly inundated with messages that being proactive is praiseworthy. But in terms of health, being proactive means exercising, getting enough sleep, maintaining a normal weight, and abstaining from unhealthy habits like drinking too much or smoking. Add to that a handful of tests for the diseases in which testing helps, and you just can’t get more proactive.

It doesn’t make sense, does it?

There are actually two reasons that screening for many diseases doesn’t help. (Remember, screening means testing for an illness in someone with no symptoms or signs of the illness.)

The first reason is just that the best treatments we have for many illnesses work the same whether the illness is diagnosed before or after it starts causing symptoms. Why test everyone for a disease that only a few people have if those few people would do as well if they just waited until they got sick? If you’re going to get leukemia, catching it early won’t help. Some leukemias are cured, and some aren’t, but it doesn’t much matter when the diagnosis is made. So it makes sense to diagnose leukemia after it makes people sick.

The second reason has to do with the harms done by testing errors.

To explain this, indulge me in a little thought experiment. Let’s pretend there’s a disease called RBD (Rare Bad Disease) that is curable if caught before symptoms start, but is rapidly fatal otherwise. But it’s rare; only one in 10,000 people has it. That sounds like a perfect opportunity for screening, right? If we just test everybody then we can cure the ones with RBD. Now the treatment must be either expensive or dangerous, because otherwise it would be simpler to just treat everyone. (That’s why we just add folic acid to flour rather than test everyone for folic acid deficiency. It’s easier and safer to treat everyone in that case.) So let’s assume that the treatment of RBD if given to a person without RBD has a one percent fatal complication rate. And let’s also imagine that we have a test for RBD that is 99% accurate.

So in a city of a million people, one hundred of them have RBD and 999,900 don’t. If we test everyone in the city, because the test is inaccurate 1% of the time, one person with RBD will falsely test negative, but almost 10,000 healthy people will test positive. If we give everyone who tests positive the treatment for RBD, we’ll be treating a hundred times more healthy people than people with RBD and we’ll be killing as many people from the treatment as we’re saving. Better to forget the screening.

Are people in real life actually harmed by screening tests? Absolutely. Primary care doctors have all seen many patients go through unnecessary angiograms because of falsely-positive screening stress tests, unnecessary biopsies because their whole-body CT scan found some benign lumps, unnecessary sleepless nights because unproven blood tests suggested cancer that wasn’t there. The number of patients actually helped from these tests is much smaller, and the peace of mind that patients have when such tests are normal is entirely illusory. They could still develop leukemia or be hit by a truck the next day.

So keep yourself healthy. And whatever you do, don’t get tested for everything.

Learn more:

If You Feel O.K., Maybe You Are O.K. (NY Times op-ed by Dr. H. Gilbert Welch)

For a wonderful review of randomness and probability which has no math, and has a section explaining the dangers of false positives even with very accurate tests, I highly recommend The Drunkard’s Walk – How Randomness Rules Our Lives by Leonard Mlodinow.

In the RBD example, above, the probability that I have RBD if I test positive is 1%, but the probability of the test being positive if I have the disease is 99%. The fact that these two numbers are not the same is very counterintuitive. We owe our understanding of these related probabilities to Thomas Bayes, an eighteenth century English mathematician and minister. Bayes’ theorem and Bayesian statistics has transformed our understanding of risk in general and medical testing in particular.

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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February 24, 2012 | 12:22 pm

Untreatable Gonorrhea – The Next Infectious Threat

Posted by Albert Fuchs, M.D.

Our old nemesis, the clap, is in the news again this month.

Gonorrhea is the second most common sexually transmitted disease in the US, with more than 600,000 cases annually. In men it usually causes pain on urination, penile discharge, or sore throat. In women it may not cause symptoms or may cause painful urination, vaginal discharge, or sore throat. If untreated, gonorrhea can spread to the fallopian tubes, joints, and heart valves. I know that most readers simply can’t hear enough about penile discharge (especially if they’re reading this over lunch), I’ve included a microscopic image of exactly that. The gonorrhea bacteria are visible as the small dark dots.

With the discovery of penicillin in the 1940s the treatment of gonorrhea was revolutionized. But ever since that major victory gonorrhea has won several important battles. Gonorrhea developed resistance to sulfanilamide in the 1940s and to penicillins and tetracyclines in the 1980s. When I trained in internal medicine in the mid 1990s, Cipro (an antibiotic in the family called fluoroquinolones) was the preferred treatment for gonorrhea. In the 2000s some fluoroquinolone-resistant strains of gonorrhea appeared and by 2007 resistance was widespread.

Third generation cephalosporins are now the last antibiotic family to which gonorrhea is susceptible. But, as a decade ago with fluoroquinolones, sensitivity to cephalosporins is slowly decreasing, especially in the western US. Though no strain in the US has become resistant yet, a strain isolated from a patient in Japan in 2009 was highly resistant to cephalosporins.

The downward creeping cephalosporin sensitivity of gonorrhea prompted CDC researchers to sound the alarm in an editorial in the New England Journal of Medicine earlier this month. The editorial warns that if the early signs of decreasing sensitivity are analogous to what we observed with fluoroquinolones in the ‘90s, then we may be only a few years away from strains of gonorrhea that are untreatable by any antibiotics.

The authors make sound recommendations to accelerate development of new antibiotics and increase surveillance of gonorrhea antibiotic sensitivity. But it’s entirely possible that these efforts will fail, and that the only defense against gonorrhea will be from a vaccine which is not expected any time soon.

I’ve written before about the emerging problem of bacterial antibiotic resistance. Our grandchildren may study the period from the 1940s to the 2040s as the antibiotic century. Unless antibiotic development stays a step ahead of the wily microorganisms we may reach a time when sexually transmitted infections are managed the way they were a hundred years ago – promoting the use of condoms and corny public health posters encouraging men to keep their flies zipped.

Learn more:

CDC Warns Untreatable Gonorrhea is On the Way (Chicago Tribune)
Gonorrhea Could Join Growing List of Untreatable Diseases (Scientific American)
Antibiotic-Resistant Gonorrhea (Centers for Disease Control and Prevention)
The Emerging Threat of Untreatable Gonococcal Infection (New England Journal of Medicine)
Gonorrhea (U.S. National Library of Medicine)

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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February 17, 2012 | 2:47 pm

Relearning What We Knew: Antibiotics Don’t Help In Sinus Infections

Posted by Albert Fuchs, M.D.

Most of us are personally familiar with the symptoms of a sinus infection – congested nose, cough, fever, pain in the forehead or cheeks, and general misery. It’s impossible not to feel sympathetic for patients with sinus infections, and it’s understandable that they want to do whatever it takes to feel better as soon as possible. And for many doctors and patients “as soon as possible” means “antibiotics”. In fact, almost one fifth of antibiotic prescriptions are given for patients with sinus infections (sinusitis).

Here’s where the story gets complicated. Doctors have known for a long time that sinus infections almost always improve even without antibiotics. Originally we thought that the reason for this was because most cases of sinusitis were caused by viruses, which are unaffected by antibiotics. It was thought that only the minority of cases of sinusitis that were caused by bacteria required antibiotics. But it turned out that even most cases of bacterial sinusitis improved on their own, with most people feeling better in ten days regardless of antibiotics.

So the prevailing teaching has long been that for acute sinusitis the best treatment is nasal decongestants and medications for the cough, pain, and fever. Only the tiny number of people who don’t improve in ten days should be prescribed antibiotics. Still, many doctors either don’t know this recommendation or acquiesce to patients’ expectations for antibiotics. I have certainly been guilty of this misuse of antibiotics many times. A sick patient pleading for antibiotics may be misguided, but he’s rarely in the mood for a lesson about the medical literature and the potential harms to society of antibiotic overuse.

Now, when you’re healthy, is a good time for that lesson, and a study in this week’s Journal of the American Medical Association is the perfect reminder. The study enrolled 166 patients with an acute sinus infection. Half were randomly assigned to receive a ten day course of amoxicillin. The other half received placebo. Both groups were also offered nasal decongestants, cough suppressants, and medicines to reduce pain and fever. Every several days, the patients were interviewed about their symptoms, their satisfaction, and any adverse effects of treatment.

You can already guess the outcome. Both groups did equally well, without any earlier resolution of symptoms for the amoxicillin group. Some doctors concede that sinusitis resolves without antibiotics, but argue that patients feel better sooner if they receive antibiotics. This study debunked that argument. Even at day three there was no difference between the two groups.

The risk of all this antibiotic use is an acceleration of the increasing prevalence of multi-antibiotic-resistant bacteria that threaten to make all our antibiotics ineffective. So the next time you see me with a terrible sinus infection, let me recommend a good nasal decongestant, and let me reassure you that there’s nothing else I can do to get you well quicker. Time is your best friend. That’s why we call you patients.

Learn more:

Got A Sinus Infection? Antibiotics Probably Won’t Help (Shots, NPR’s Health Blog)
Sinus infection? Antibiotics won’t help (CNN Health)
Antibiotics Do Nothing to Cure Sinus Infections, Study Says: Most cases resolve on their own, and use of drugs can encourage resistance, researchers say (Chicago Tribune)
Amoxicillin for Acute Rhinosinusitis (Journal of the American Medical Association)
NDM-1: No Drug Matters (my most recent post about antibiotic resistance)

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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February 10, 2012 | 5:32 pm

Tai Chi Improves Balance in Patients with Parkinson’s

Posted by Albert Fuchs, M.D.

Parkinson’s disease is a progressive neurologic disorder. Parkinson’s biggest initial impact is on how patients move. Patients have tremors and have difficulty initiating movement. They walk with short shuffling steps. Balance worsens and falls are common. Parkinson’s disease is treated with medications and rarely with brain surgery. Resistance-based exercise has been shown to slow the worsening of balance and strength in patients with Parkinson’s disease, but these exercises frequently require equipment and supervision.

Tai chi is an ancient Chinese martial art. Its emphasis on slow graceful movements, balance, and attention to breathing has made it a very popular form of exercise and meditation. Researchers thought that it would be a good way to improve balance in Parkinson’s patients. A study published in this week’s New England Journal of Medicine shows they were right.

The study enrolled 195 ambulatory Parkinson’s patients to three groups. Each group attended a sixty minute exercise class twice a week for six months. One group attended tai chi classes. A second group attended resistance-based strength training classes. A third group (the control group) did stretching.

All patients had objective measures of their balance and gait and kept a log of any falls. They were followed for three months after the end of their exercise classes.

As expected, the tai chi and strength training groups had better test results than the stretching group in measures of walking and strength. But he patients who did tai chi had better balance than the other two groups and also had fewer falls. The benefits persisted even three months after the end of the classes. And there were no serious adverse effects, which would be unheard of in a trial of a medication or surgery.

This reveals an appealing opportunity for Parkinson’s patients – exercises that require no equipment, can be learned and then practiced at home without assistance, and are relatively inexpensive. Though there is no evidence generalizing this finding to other causes of balance disorder, like strokes or Alzheimer’s disease, tai chi seems to me to be a very reasonable and harmless intervention in these disorders too.

Perhaps next we will learn that Krav Maga cures gallstones.

Learn more:

Tai Chi may help Parkinson’s patients regain balance (Los Angeles Times Booster Shots)
Slow movements of tai chi helped with balance, reduced falls in Parkinson’s disease study (Washington Post)
Tai Chi and Postural Stability in Patients with Parkinson’s Disease (New England Journal of Medicine)

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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February 3, 2012 | 7:34 am

Amputations in Diabetics Decline Dramatically

Posted by Albert Fuchs, M.D.

Diabetes can lead to numerous serious complications. It is a major risk factor for stroke and heart attack. Diabetes can damage the retina and is the leading cause of new cases of blindness in the US. It can damage the kidneys and is the greatest cause of need for dialysis. It can also cause nerve damage leading to numb or painful feet.

But few potential complications evoke as much fear in my patients as foot amputations. Though many injuries and accidents lead to amputations, diabetes is the most frequent cause of nontraumatic foot amputation. Diabetes leads to limb loss through multiple mechanisms. It leads to atherosclerosis, cholesterol plaques in arteries, which limit circulation to the limbs. It leads to nerve damage which can cause wounds to go unnoticed. And it weakens the immune response so that infected wounds are very difficult to treat.

The good news this week is that amputations due to diabetes have become much less frequent. A study conducted by the Centers for Disease Control and published in Diabetes Care reviews nontraumatic lower extremity amputations in diabetics between 1996 and 2008. In those twelve years the frequency of amputation in diabetics declined by two thirds.

Many helpful trends are responsible for all those saved feet. Diabetes is typically diagnosed earlier and treated more aggressively now than in the mid 90s. Several of the medications used for diabetes now were unavailable then. Atherosclerosis treatment also continues to improve with recognition of the importance blood pressure control and of cholesterol lowering with statins. The importance of meticulous foot care by diabetic patients is better understood, and the management of diabetic wounds by multidisciplinary teams is becoming the standard of care.

So in a week in which the news appears monolithically depressing I thought I’d spread some good news. Chances are you know someone with diabetes. Chances are that he will continue to lace both of his shoes for his whole life.

Learn more:

CDC report finds large decline in lower-limb amputations among U.S. adults with diagnosed diabetes (CDC Press Release)
Lower-limb amputations have declined among diabetics (Los Angeles Times Booster Shots)
Rate of Leg, Foot Amputations Among Diabetics Drops: CDC (US News & World Report)
Declining Rates of Hospitalization for Nontraumatic Lower-Extremity Amputation in the Diabetic Population Aged 40 Years or Older (Diabetes Care)

Tangential Miscellany

Dr. Kevin Pho, the very well known physician blogger and outspoken advocate of social media in medicine, is publishing some of my posts.

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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January 27, 2012 | 5:46 pm

Major Study Examines Causes of Morgellons

Posted by Albert Fuchs, M.D.

The name Morgellons originated in 2002. That year a mother took her young son to doctors reporting that he was complaining of “bugs” in his skin. He had sores under his lips and the mother reported seeing fibers in these sores. She named her son’s illness Morgellons and started a website to raise awareness and research funding for the disorder. The boy’s doctors found no specific abnormality and believed that the mother was suffering from a psychiatric condition.

Since then many patients have presented to medical attention reporting disturbing skin sensations (sometimes described as something crawling on top of or under the skin), skin sores, and various forms of solid material coming out of their skin, frequently fibers or threads. Many of the physicians examining these patients believed that they suffered from delusional infestation (also known as delusional parasitosis), a disorder in which patients are convinced that they are infested with parasites or other germs. Delusional infestation (DI) has been described for over a century and is very difficult to treat. All tests checking for an infectious or allergic cause are of course negative, but patients are not reassured by the normal results. They are agitated that the physician has (again) failed to discover the cause. The patients never respond well to factual evidence arguing against their delusion and typically refuse psychiatric referral.

The generally recommended approach in DI is for the dermatologist or primary-care physician to build a trusting relationship by acknowledging the patient’s distressing symptoms and the disruption that the symptoms cause in the patient’s life. (This is neither patronizing nor dishonest. Patients with DI are frequently quite fixated on their symptoms and the disease frequently strains relationships and careers.) Rather than confront patients with the diagnosis of DI, doctors are encouraged to use the synonymous but less judgmental term “unexplained dermopathy”. Occasionally physicians are able to convince patients to try antipsychotic medications by offering them as a way to decrease the skin symptoms and explaining that others with the same disease have done well with this medication. Some patients achieve relief with these medications, though it’s not clear how frequently.

So DI is a particularly difficult condition to treat, because a defining characteristic of the condition is the unwillingness to accept the diagnosis. That makes the doctor-patient relationship very difficult, since the physician needs to earn the patient’s trust without being fully transparent. Imagine if one of the universal characteristics of diabetes was the refusal to believe that one has diabetes.

Add to these difficulties the wonders of the internet. Patients with Morgellons, feeling wrongly dismissed by doctors who diagnosed them with DI and confident that their disease is caused by an infection or an environmental exposure, have used the web to organize and lobby Congress for a study to determine the cause of their affliction. So between 2006 and 2008 the Centers for Disease Control did just that, in the largest study of Morgellons to date. The findings of the study was published this week in PLoS ONE and summarized on the CDC website.

The study enrolled 115 patients in Northern California with symptoms matching Morgellons. Patients were put through a systematized and extensive diagnostic work up, including a detailed demographic survey, a comprehensive history and physical examination, photographs of the whole body and of individual skin lesions, skin biopsies, analysis of any foreign material found on the skin, and numerous lab tests of blood, urine, and hair.

The results show that Morgellons (or unexplained dermopathy) is rare, affecting about 4 people in 100,000. Three quarters of patients are female, and three quarters are Caucasian. Most are middle-aged. The exhaustive evaluation failed to find a common infectious or environmental cause of the disorder. Significantly, the patients’ residences don’t cluster geographically, which would be expected with an infectious illness.

The skin lesions varied substantially and didn’t demonstrate one homogenous type. The location of the skin lesions was fascinating. Most arm lesions were on the back of the arms with sparing of the front surfaces. Back lesions usually spared the center of the back. Lesions that originated in the skin would be expected to be more uniform in distribution. A disease that originates with scratching otherwise healthy skin will show lesions where people preferentially scratch. Skin biopsies showed mostly the consequences of chronic scratching, bug bites, or the effects of chronic sun damage that is common in California. The fibers were mostly cotton fibers common in clothes.

Psychological testing showed abnormal attention to bodily symptoms in two thirds of patients. Half had recreational drugs detected in their hair samples.

The authors conclude:

This unexplained dermopathy was rare among this population of Northern California residents, but associated with significantly reduced health-related quality of life. No common underlying medical condition or infectious source was identified, similar to more commonly recognized conditions such as delusional infestation.

In the absence of an established cause or treatment, patients with this unexplained dermopathy may benefit from receipt of standard therapies for co-existing medical conditions and/or those recommended for similar conditions such delusional infestation.

This is very helpful information obtained through much meticulous work. But how will it be received? What happens when the internet, a global engine of transparency and information sharing, collides with a disorder that reacts poorly to the truth?

Learn more:

CDC Study Finds Fibers Aren’t Cause of Morgellons (Wall Street Journal Health Blog)
Morgellons not caused by infectious agent, CDC researchers say (Los Angeles Times Booster Shots)
CDC Study of an Unexplained Dermopathy (Centers for Disease Control and Prevention)
Clinical, Epidemiologic, Histopathologic and Molecular Features of an Unexplained Dermopathy (PLoS ONE)
Morgellons (Wikipedia)

Important legal mumbo jumbo:
Anything you read on the web should be used to supplement, not replace, your doctor’s advice.  Anything that I write is no exception.  I’m a doctor, but I’m not your doctor.

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