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About jamesmarroquin.com

I am an internist in private practice in Austin, TX. I am also fellowship-trained/board certified in palliative care. I’m an assistant professor at UT Dell Medical, teaching in the clinical skills course. My goals for this blog are to provide information on health and health care, consider philosophical, political, theological issues related to medicine, and make sense of my experience as a physician. I am married with 2 sons.

All About Blood Pressure

Blood pressure is not one of the most interesting and sexy subjects in health science. In contrast to the latest findings about the brain, learning more about hypertension is unlikely to evoke wonder or yield new insights into the meaning of human life and the universe.  Moreover, treating high blood pressure probably won’t make an immediate difference in how a person feels.  In fact, the vast majority of people with high blood pressure (otherwise known as hypertension) do not have any symptoms from the condition.  This is why it has been called the silent killer. 

On the other hand, hypertension is common.  By one estimate, 90% of people who live to age 80 will have developed high blood pressure.  Left untreated, it can lead to heart attacks and strokes, as well as kidney and heart failure.  Hypertension is usually easy to treat with medications that are inexpensive and well tolerated.  In my work with hospice, I sometimes see people dying of these conditions at an early age because their hypertension was never addressed and treated. 

So what exactly is blood pressure? It is the pressure in our arteries, those vessels that bring blood to all the cells in our body.  Blood pressure is recorded as 2 numbers, for example 120/80.  The top number is called the systolic blood pressure and is the pressure in the arteries when the heart contracts (systole).  The bottom number, termed the diastolic blood pressure, is the pressure when the heart relaxes (diastole). 

According to the most recent guidelines, hypertension for people less than 60 years old is defined as having an average blood pressure greater than 140/90.  For people, greater than age 60, the new blood pressure goal is having an average less than 150/90.  Keeping an individual’s average blood pressure less than these levels markedly lowers his or her risk of having heart attacks, strokes, kidney and heart failure.

How do you know if you have high blood pressure?  Since hypertension usually doesn’t cause any symptoms, you have to check your reading to be aware of its presence.  This can be done at your doctor or dentist’s office, using a cuff commonly found at pharmacies, or by buying an easy to use home blood pressure machine.  When assessing your blood pressure, it is important to remember that it is the average readings you see that count.  So don’t get worried about a few stray high numbers.  But if you have blood pressure readings that are persistently in the hypertensive range, it is important to see your physician for a discussion.

Some lifestyle measures for preventing and treating hypertension are a low salt diet, regular aerobic exercise, stress management, maintaining a healthy weight, abstaining from heated discussions about Duck Dynasty on Facebook, and avoidance of Dallas Cowboy television viewing.

 
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Posted by on December 23, 2013 in Uncategorized

 

The Bugs in our Gut

Over the past year, a number of interesting studies have shed light on the hitherto unknown functions of the bacteria that live in our gut.  Researchers at UCLA found that women who regularly consumed beneficial bacteria through yogurt showed altered brain function, both while in a resting state and in response to an emotion-recognition task.  Commenting on the study published in Gastroenterology, lead author Dr. Kirsten Tillisch noted that “our findings indicate that some of the contents of yogurt may actually change the way our brain responds to the environment. When we consider the implications of this work, the old sayings ‘you are what you eat’ and ‘gut feelings’ take on new meaning.”  An article linked here provides further insight into the study and its significance.

Researchers have known that the brain sends signals to the gut, which is why stress and other emotions can contribute to gastrointestinal symptoms. This study shows what has been suspected but until now had been proved only in animal studies: that signals travel the opposite way as well.

“Time and time again, we hear from patients that they never felt depressed or anxious until they started experiencing problems with their gut,” Tillisch said. “Our study shows that the gut–brain connection is a two-way street.”

The small study involved 36 women between the ages of 18 and 55. Researchers divided the women into three groups: one group ate a specific yogurt containing a mix of several probiotics — bacteria thought to have a positive effect on the intestines — twice a day for four weeks; another group consumed a dairy product that looked and tasted like the yogurt but contained no probiotics; and a third group ate no product at all.

Functional magnetic resonance imaging (fMRI) scans conducted both before and after the four-week study period looked at the women’s brains in a state of rest and in response to an emotion-recognition task in which they viewed a series of pictures of people with angry or frightened faces and matched them to other faces showing the same emotions. This task, designed to measure the engagement of affective and cognitive brain regions in response to a visual stimulus, was chosen because previous research in animals had linked changes in gut flora to changes in affective behaviors.

The researchers found that, compared with the women who didn’t consume the probiotic yogurt, those who did showed a decrease in activity in both the insula — which processes and integrates internal body sensations, like those from the gut — and the somatosensory cortex during the emotional reactivity task.

Further, in response to the task, these women had a decrease in the engagement of a widespread network in the brain that includes emotion-, cognition- and sensory-related areas. The women in the other two groups showed a stable or increased activity in this network.

During the resting brain scan, the women consuming probiotics showed greater connectivity between a key brainstem region known as the periaqueductal grey and cognition-associated areas of the prefrontal cortex. The women who ate no product at all, on the other hand, showed greater connectivity of the periaqueductal grey to emotion- and sensation-related regions, while the group consuming the non-probiotic dairy product showed results in between.

The researchers were surprised to find that the brain effects could be seen in many areas, including those involved in sensory processing and not merely those associated with emotion, Tillisch said.

The knowledge that signals are sent from the intestine to the brain and that they can be modulated by a dietary change is likely to lead to an expansion of research aimed at finding new strategies to prevent or treat digestive, mental and neurological disorders.

So how do we change the bacteria in our gut?  A recent study published in Nature showed that changing the food you eat rapidly changes the composition of your gut bacteria.  In the study, researchers had nine volunteers go on two extreme diets for five days each.  In the first diet, volunteers ate eggs and bacon for breakfast, ribs and briskets for lunch, and an assortment of pork meat and cheeses for dinners.  Then after a break, the nine volunteers ate a diet that consisted almost entirely of plants. They had granola cereal for breakfast, and for lunch and dinner a combination of jasmine rice, cooked onions, tomatoes, squash, garlic, peas, lentils, bananas and mangoes.

Researchers analyzed the volunteers’ microbiomes before, during and after each diet.  Lead researcher Lawrence David noted that “the relative abundance of various bacteria species looked like it shifted within a day after the food hit the gut.”  After the volunteers had spent about three days on each diet, the genes which the bacteria expressed began to change.  The bacteria found in people’s guts after they ate an animal-rich diet have previously been associated with higher levels of inflammation in the body.  An NPR article on the study is linked here.

Overall, studies like these show that what we eat affects our health in ways that we have not previously appreciated.

 
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Posted by on December 19, 2013 in Uncategorized

 

How Do Antidepressants Work?

I remember feeling puzzled when I first learned how antidepressants worked in medical school.  This much made sense to me: Chemicals called neurotransmitters enable neurons (nerve cells) to communicate with each other.  Some important and commonly known neurotransmitters are serotonin, norepinephrine, and dopamine.  The space between neurons is called a synapse.  When a neurotransmitter such as serotonin or norepinephrine is released and travels between neurons, some of it gets reabsorbed into the neuron that released it.  Antidepressants block serotonin, norepinephrine, and other neurotransmitters from being reabsorbed into neurons.  This allows for a greater amount of neurotransmitter to remain in the space between neurons. 

But what puzzled me as I learned about antidepressants is why having a greater amount of neurotransmitter in the space between neurons should translate into treating depression.  Recently, Scientific American published an article addressing this very question.  In it, Alan Gelenberg, a depression and psychiatric researcher at Pennsylvania State University, remarks that “there’s really no evidence that depression is a serotonin-deficiency syndrome.  It’s like saying that a headache is an aspirin-deficiency syndrome.”  Here he is saying that just because aspirin can relief a headache, this does not mean that headaches are caused by a low level of aspirin in our body.  Analogously, just because medications that raise serotonin levels in our synapses help treat depression, this does not mean that depression is due to a low level of serotonin our synapses.

The article notes that

research headed up by neuroscientists David Gurwitz and Noam Shomron of Tel Aviv University in Israel supports recent thinking that rather than a shortage of serotonin, a lack of synaptogenesis (the growth of new synapses, or nerve contacts) and neurogenesis (the generation and migration of new neurons) could cause depression. In this model lower serotonin levels would merely result when cells stopped making new connections among neurons or the brain stopped making new neurons. So, directly treating the cause of this diminished neuronal activity could prove to be a more effective therapy for depression than simply relying on drugs to increase serotonin levels.

 

Evidence for this line of thought came when their team found that cells in culture exposed to a 21-day course of the common SSRI paroxetine (Paxil is one of the brand names) expressed significantly more of the gene for an integrin protein called ITGB3 (integrin beta-3). Integrins are known to play a role in cell adhesion and connectivity and therefore are essential for synaptogenesis. The scientists think SSRIs might promote synaptogenesis and neurogenesis by turning on genes that make ITGB3 as well as other proteins that are involved in these processes. . . Of the 14 genes that showed increased activity in the paroxetine-treated cells, the gene that expresses ITGB3 showed the greatest increase in activity.

These results were published in the October 15 issue of Translational Psychiatry.  Conceiving of depression as an impairment in the generation of neurons and the connections between them makes sense of the symptoms present in severe depression.  If the neurological processes required for learning and engaging the world are not functioning, then it stands to reason that a person will have a decreased ability to concentrate, reason, retain information, and take pleasure in life.  Time will tell if this new paradigm for understanding depression will generate more effective therapies for this often debilitating condition.

The Scientific American article is linked here.

 
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Posted by on December 15, 2013 in Uncategorized

 

Inheriting Trauma

Could a trauma that you experienced be passed on to your children or grandchildren?  Could your anxieties be related to something that happened to your parents or grandparents?  A fascinating new study published in Nature Neuroscience suggests that information, such as our responses to life experiences, can be passed on.  

A Washington Post article reports that In an experiment, researchers

taught male mice to fear the smell of cherry blossoms by associating the scent with mild foot shocks. Two weeks later, they bred with females. The resulting pups were raised to adulthood having never been exposed to the smell.  

 

Yet when the critters caught a whiff of it for the first time, they suddenly became anxious and fearful. They were even born with more cherry-blossom-detecting neurons in their noses and more brain space devoted to cherry-blossom-smelling.

 

The memory transmission extended out another generation when these male mice bred, and similar results were found.

 

Neuroscientists at Emory University found that genetic markers, thought to be wiped clean before birth, were used to transmit a single traumatic experience across generations, leaving behind traces in the behavior and anatomy of future pups.

 

The Post article reports that this study 

adds to a growing pile of evidence suggesting that characteristics outside of the strict genetic code may also be acquired from our parents through epigenetic inheritance. Epigenetics studies how molecules act as DNA markers that influence how the genome is read. We pick up these epigenetic markers during our lives and in various locations on our body as we develop and interact with our environment.

 

Through a process dubbed “reprogramming,” these epigenetic markers were thought to be erased in the earliest stages of development in mammals. But recent research — this study included — has shown that some of these markers may survive to the next generation.

 

Until recently, the scientific consensus was that life experiences could not be passed on to offspring.  

“When I was in school, this was against Darwin — it was ridiculed,” said University of Pennsylvania neuroscientist Christopher Pierce, who was not involved in the study but previously discovered an epigenetic inheritance related to cocaine. Male rats whose fathers were exposed to cocaine chose to ingest less of the drug than those rats whose fathers never took cocaine.

The Washington Post article goes on to ask whether we as humans have also inherited generations of fears and experiences.  

Quite possibly, say scientists. Studies on humans suggest that children and grandchildren may have felt the epigenetic impact of such traumatic events such as famine, the Holocaust and the Sept. 11, 2001, terrorist attacks.

 

Read the Washington Post article here and the Nature Neuroscience article here.

 

 
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Posted by on December 9, 2013 in Uncategorized

 

Hospital

Here’s a review I wrote for the Journal of Palliative Medicine on a book by Julie Salamon called Hospital: Man, Woman, Birth, Death, Infinity, plus Red Tape, Bad Behavior, Money, God, and Diversity on Steroids.

The discipline of palliative care emerged from careful observation and consideration of modern health care.  Pioneers such as Dame Cicely Saunders and Balfour Mount studied how people were being treated at the end of their lives and asked if there was a better way.  In this tradition, palliative care practitioners continue to monitor and try to make sense of how contemporary technological, economic, social, and political forces are shaping modern medicine.  For anyone performing this reflective task, Julie Salamon’s Hospital may be an illuminating resource.  The book is a journalist’s account of a year spent in Brooklyn’s Maimonides Medical Center with unrestricted access to the hospital and its personnel.  Searching for the universe in a grain of sand, Salamon hopes the story of this large urban hospital will help tell the larger story of American medicine at the beginning of the twenty-first century.

The story that emerges is one of ever increasing industrialization.  While Maimonides’ staff clearly strives to do what is best for their patients, the institution’s driving ethos is efficiency and financial success.  As the hospital’s chief of surgery explains to Salamon, “It’s all about patient turnover.  The more you can get in and out, the more times that cash register rings.  It sounds like business and it is business. . . We’re not kicking them out.  But if you get them out two days later, for every discharge you lose, you’re losing ten thousands bucks.”  Like a factory mass producing a standardized product, the care at Maimonides relies upon treatment protocols  derived from evidence-based medicine that applies to the everyman of population studies rather than the individual patients of the real world.  In its growing emphasis on medical specialization, the hospital incorporates the basic industrial principle of division of labor.  Finally, just as the industrial revolution saw the rise of a managerial class to organize and maximize production, so Maimonides has an administrative superstructure headed by its chief executive officer Pamela Brier, a business-savy MBA.

The industrialization of American medicine exemplified in Salamon’s portrayal of Maimonides has clear merits.  To remain financially solvent enough to carry out their mission of patient care, hospitals must pay close attention to efficiency and the bottom line.  Treatment protocols derived from evidence-based medicine promote consistency and quality of care.  And with the logarithmic growth of medical knowledge, more and more specialization is necessary to effectively bring scientific developments to bear on patient treatment.

But as Salamon’s book shows, medicine’s industrial shift comes at considerable cost.  It is the cost of the alientation that pervades the pages of Hospital.  At Maimonides, physicians and patients often feel estranged from the healing physician-patient relationship that has traditionally been the heart of medicine.  As one physician tells Salamon, “The past few decades, patients have been saying, ‘I feel I’m just a machine, a widget on the assembly line.’  But lots of doctors are now beginning to experience that, because of the medical industrial complex that treats doctors as another widget.  It’s all interchangeable parts, and the chief virtue becomes efficiency rather than caring compassion.  Lots of physicians are feeling a sense of emptiness, alienation:  ‘Is this why I went into this? Is this what it’s about?. . . Is there more than just thinking about how many colons I can put a scope up per day and how many polyps I can remove and how fast I can be and how few complications I can get?”

The character of Davey Gregorius shows how medical industrialization has shaped the next generation of physicians’ views of their profession.  Gregorius is a first-year resident in emergency medicine at Maimonides who harbors no quixotic aims for his career after finishing his training.  He plans on a job in an emergency department in the Colorado mountains, where he can work two to three shifts a week to finance a life of plentiful skiing and fishing.

Gregorius spends the majority of his time during emergency department shifts in front of a glowing computer screen monitoring patient test results and documenting his work.  Rather than learning about patients’ conditions through listening to their stories and physically examining them, most of Gregorius’ diagnostic information comes through a battery of labs and imaging tests he has ordered.  We see here how modern medicine’s ever-growing diagnostic technology sometimes alienates patients and physicians from each other.  We also see how much time the modern American physician spends breaking down her care for patients into artificial units of value that a third-party payer has devised to determine compensation.  But none of this seems to bother Davey Gregorius.  He does not romantically long for a bygone era in which medicine was a deeply meaningful, even noble profession.  Gregorius instead pragmatically views being a doctor as interesting shift-work that provides adequate compensation to pursue his true passions.  

In contrast, Allan Astrow is determined to preserve the idea of medicine as a deeply moral enterprise.  Astrow in an oncologist whose formative years as a physician were spent in the 1980s and 1990s treating AIDS-related malignancies in a Greenwich Village hospital. Over against the idea of health care as a commodity, he believes that medicine is a covenant between the practitioner whom society has entrusted with the power of healing and the sick person who is in a uniquely dependent, vulnerable, and anxious state.  Astrow has come to Maimonides to take over as associate director of its medical oncology department.  It is an administrative position in which he’ll have to concern himself with efficiency and the bottom line, something seemingly ill-suited for this idealistic man.  But as an outspoken critic of medicine’s industrialization, Astrow feels a duty to get involved in the muck of the system to try to improve it.  It is an admirable, but deceptively perilous endeavor.  Will a position where success is often measured in financial terms distract Astrow from his commitment to medicine’s higher calling?  Will the system change him more than he is able to change it?

His dilemma is akin to one that palliative care faces as it searches for its place in twenty-first century American medicine.  Should the field see itself as comfortably fitting into the industrial division of patient care into component tasks?  Is our place at the end of the health care conveyer belt, taking over patient care at the end of life from hospitalists who were handed the care baton from internists upon hospital admission?

Or should palliative care consider itself a protest against medicine’s industrial trend?  After all, as medicine becomes more and more specialized, palliative care self-consciously takes a holistic approach to patient care.  As futuristic medical technology becomes today’s reality, palliative care’s special procedure is effective interpersonal communication.  As medical research promises scientific certainty and miracle cures, palliative care embraces the art and limits of medicine.

Ultimately, of course, palliative care must continue to seek integration into America’s modern health care system.  Doing so is necessary for the field to have its greatest possible impact.  But palliative care must also intentionally and rigorously guard against attempts to downplay or alter its core commitments in the name of medicine’s infinite quest for maximal efficiency.  For these core commitments are what gave birth to the field and remain its most valuable contribution to medicine.

 

 
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Posted by on December 6, 2013 in Uncategorized

 

Give Dem Nuts Some Respect

I am struggling for a clever way to introduce a New England Journal of Medicine article on the health benefits of nuts.  Nuts for nuts?  Nutty study?  Since this is a family blog, I won’t venture into more riskee territory.

Anyway, nuts are a nutrient-rich food, full of fiber, vitamins, minerals, and unsaturated fatty acids.  And a recent randomized trial showed that eating a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of heart attacks and strokes in people at risk for these health problems.

Now an analysis of two studies sheds further light on the health benefits of nuts.  For decades, researchers have gathered data on nurses and other health care workers.  The investigators separated the participants into groups based on their nut consumption, and looked at how their outcomes compared to those who didn’t eat nuts.  “They found that those who ate nuts the most frequently – at least seven times a week – had a 20 percent lower risk of dying than those who didn’t eat nuts at all. . . Nut eaters were less likely to die from heart disease, cancer or respiratory diseases. The type of nut didn’t seem to matter – peanuts were just as good as tree nuts, a category that includes cashews and almonds.”

The investigators then conducted statistical analyses to determine whether it was eating nuts – rather than some other characteristic of those who eat nuts – that was directly associated with decreased mortality.  Even after making these adjustments, the association between nut intake and longer life held up.

The authors of this study acknowledge that because it is observational, it cannot prove that nuts will make you live longer.  We will need a different king of study–a randomized controlled trial–to do that.  In the mean time, though, it surely can’t hurt to add some almonds, pecans, cashews, and other tasty nutty treats to your plate.

Here is a link to a fun little video explaining the study recently published in the New England Journal of Medicine.

 
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Posted by on December 4, 2013 in Uncategorized

 

The Story of Stress

Everyday in my medical practice, I see people experiencing health problems generated or worsened by stress.  In her book, The Cure Within, Harvard historian Anne Harrington tells the story of how scientists discovered stress’s harmful effects. 

The story begins with a physiologist named Walter Cannon.  Cannon was using newly developed X-ray technology to study peristalsis—the intestinal movements needed for digestion.   As Harrington writes:

“Cannon found that whenever his experimental animals—mostly cats—became distressed or enraged, their peristaltic activity was inhibited.  This led to new questions:  Why should distress or rage inhibit peristalsis? What did emotions and digestion have to do with each other?

To answer these questions, Cannon agitated cats by having dogs sniff and bark at them.  He then drew blood from the agitated cats and compared it with blood taken cats who had not been threatened.  Cannon found that the blood of the frightened cats contained a chemical adrenin (today called epinephrine or adrenaline).  Injecting adrenin into an animal resulted in higher blood pressure and glucose levels, inhibition of digestion, and dilation of the pupils.  Considering this data, Cannon had the insight that the physiologic changes he noted in the animals he stressed would be useful for either fighting or fleeing from an enemy.  

As Harrington writes, 

“Cannon’s next move was key.  He noted that human beings have the same capacity as other animals for fight or flight reactions;  we too have homeostatic systems to help us regulate the use of these reactions in response to environmental challenges and threats.  In the modern era, however, Cannon suggested that life had become so fast paced, so uncertain, and consequently so anxiety-provoking that many people went through their days as if they were cats faced with dogs perpetually barking at them.  With their ’emergency’ responses thus chronically stimulated, there were few opportunities for homeostatic mechanisms to restore their physiologies to a resting state.

The work of physician and biochemist Hans Selye further advanced our understanding of stress.  Selye was working with other scientists to identify a new female sex hormone.  He injected extract from the ovaries of freshly slaughtered cows into female rats, studying how their bodies responded.  When Selye performed autopsies on “he was disappointed to see there had been no change in their sex organs.  However they did all suffer from a curious triad of symptoms;  peptic ulcers, enlarged adrenal glands; and shrunken immune tissues.”  When Selye injected the extracts of other organs such as kidneys and spleens into the rats, he noticed the same response.  “Then he had a new thought:

Perhaps what the rats were experiencing was not a specific response to a specific agent but a nonspecific response to the trauma of having a noxious substance injected into their bodies.  He began to wonder if other kinds of trauma would result in the same outcome–and experimented by making life very unpleasant for many rats.  Some were put on the roof of the medical buildings in the winter; some were put down in the heat of the boiler room; some underwent an operation in which their eyelids were sewn back and they were exposed to bright lights; some were placed inside barrel-like, revolving treadmills powered by an electric motor that forced them into a state of complete exhaustion.  ‘It gradually turned out,’ he later said, ‘that no matter type of damage I inflicted on an experimental animal, if it survived long enough and the stressor was sufficiently strong, the typical combination would be produced: adrenal hyperactivity, lymphatic atrophy, and peptic ulcers.’ ”  

Selye named the rats’ response to their burdensome conditions “stress” and wondered if it could be behind many of the common, but poorly understood health disorders that occur in humans.  He took his stress theory to a wide variety of audiences, including doctors, the military, and the public at large.  The idea caught on, generating more and more fruitful research into stress’ effects on our bodies.  

 
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Posted by on December 2, 2013 in Uncategorized

 

It’s OK to Wake Up In the Middle of the Night

Like many of the patients I see, I sometimes struggle to get a good night’s sleep.  One valuable lesson from my experience with insomnia is that worrying about sleep makes it even more difficult to do.  When we become anxious, our body’s fight or flight system becomes activated.  Our adrenal glands secrete norepinephrine, epinephrine, and cortisol in preparation for taking on a threat to our survival.  All of this is not a recipe for sound slumber. 

 

So if I happen to wake up in the middle of the night, I try to tell myself in a Stuart Smiley kind of voice, “It’s gonna be OK. It’s not the end of the world if I don’t get all of the sleep I want tonight.”  I also tell myself that it’s perfectly normal to wake up during the night—because it is.

 

In fact, as David Randall reports in his book Dreamland, scholars from two different fields of study have discovered that sleep hasn’t always been the long block we consider it today.  The first of these scholars is Virginia Tech history professor Roger Ekirch.  Reading documents and literature from prior days, Ekirch

kept noticing strange references to sleep.  In the Canterbury Tales, for instance, one of the characters in “The Squire’s Tale” wakes up in the early morning following her ‘first sleep’ and then goes back to bed.  A fifteenth-century medical book, meanwhile, advised readers advised readers to spend the ‘first sleep’ on the right side and after that to lie on their left.  And a scholar in England wrote that the time between the ‘first sleep’ and the ‘second sleep’ was the best time for serious study.

 

Ekirch rediscovered a fact of life that was once as common as eating breakfast.  Every night, people fell asleep not long after the sun went down and stayed that way until some time after midnight.  This was the first sleep that kept popping up in the old tales.  Once a person woke up, he or she would stay that way for an hour or so before going back to sleep until morning–the so-called second sleep.  The time between the two bouts of sleep was a natural and expected part of the night and, depending on your needs, was spent praying, reading, contemplating your dream, urinating, or having sex.  

 

While it was clear to Ekirch that modern people sleep quite differently than our ancestors, “saying that the whole of the industrialized world sleeps unnaturally was a big leap.” It was thus fortuitous that at the same time was Ekirch was making his discovery, a neuroscientist stumbled upon the same phenomenon.  At the National Institute of Mental Health, the psychiatrist Thomas Wehr wondered if “the ubiquitous artificial light we see every day could have some unknown effect on our sleep habits.  On a whim, he deprived subjects of artificial light for up to fourteen hours a day in hopes of re-creating the lighting conditions common to early humans.”  Wehr noticed that the people he studied “began to stir a little after midnight, lie awake in bed for an hour of so, and then fall back to sleep again. It was the same sort of segmented sleep that Ekirch  found in the historical records. . . The experiment revealed the innate wiring in the brain, unearthed only after the body was sheltered from modern life.”

Wehr soon decided to investigate further.  Once again, he blocked subjects from exposure to artificial light.  This time, however, he drew some of their blood during the night.  The results showed that the hour humans once spent awake in the middle of the night was probably the most relaxing block of time in their lives.  Chemically, the body was in a state equivalent to what you might feel after spending a day at a spa.  During the time between the two sleeps, the subjects’ brains pumped out higher levels of prolactin, a hormone that helps reduce stress. . . The subjects in Wehr’s study described the time between the two halves of sleep as close to a period of meditation.

 

Learning these fascinating facts about the history and biology of sleep makes me wonder if insomnia is largely an environmentally-produced health condition.  Just as asbestos produces mesothelioma and tobacco smoke accounts for most cases of lung cancer and emphysema, much of our modern plague of difficulty sleeping can be laid at the feet of Thomas Edison’s world-changing invention.

 
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Posted by on November 30, 2013 in Uncategorized

 

Shutting Down 23andMe

23andMe is a personal genomics and biotechnology company which for $99 conducts a comprehensive analysis of your DNA.  In recent days, the Food and Drug Administration (FDA) instructed 23andMe to halt sales of its main product.  The FDA’s problem with 23andMe does not seem to be the accuracy of their testing methods.  Reading NIH director Francis Collins’ book The Language of Life, in which he describes his experience using 23andMe, it seems evident that this uber-informed genetic scientist trusts the validity of their results.   The FDA’s concern is apparently that the company has not met all of the complex regulatory requirements demanded by the type of entity the FDA considers them to be. 

In his Slate article, Gary Marchant argues that the FDA’s burdensome regulations essentially make it impossible for companies to provide affordable personalized genetic testing.  

The problem is that (the FDA’s) regulatory approval pathways generally require clinical testing that takes several years to complete and costs millions of dollars. 23andMe or any other entrant into this field would have to pursue such approval for each test it offers—and 23andMe offers tests for more than 250 diseases and conditions. Moreover, because of rapid advances in the field of genetics, any such test would likely be outdated, replaced by a more precise and advanced test, before the clinical testing and regulatory approval could be completed for the initial test. In other words, the PMA regulatory pathway is infeasible and impracticable for these types of tests, and the FDA’s insistence on such a step is a death sentence for direct-to-consumer genetic testing.

 

Beyond debating the technical legalities of the FDA’s action, it is worth considering whether what it did will result in more overall harm or good.  Let’s first consider the benefits of direct-to-consumer genetic testing.  The first is privacy.  As Marchant writes, “To many people, their genetic information is very private, and they prefer to get the results privately at home rather than through their physician, who will likely put the information in the patient’s medical record.”  A second benefit is the low price of 23andMe’s product.  To quote Marchant again, “It is much cheaper to get tested through 23andMe, which is currently offering its entire battery of genetic tests for only $99. It would cost many hundreds if not thousands of dollars to get the same tests through one’s physician, and health insurance does not cover the cost of most genetic tests presently.”

What are the concerns held by the FDA and other critics of direct-to-consumer genetic testing?  One worry is that people might undergo unnecessary tests and procedures based on the information 23andMe provides.  For example, critics worry that a woman who is found to have a false-positive BRCA mutation might have a prophylactic mastectomy inappropriately.  This seems to me to be an impractical concern.  It is difficult imagine a surgeon operating in such a situation without first verifying the genetic testing through another lab and extensively discussing the benefits and risks of such an approach with the patient.  

Another concern about direct-to-consumer genetic testing is the psychological impact that the information can have.  How might a person react if he or she finds they have an increased risk of developing Alzheimer’s disease, something which they are powerless to prevent?  When I received my 23andMe results, it was apparent that the company takes this issue seriously.  The results for my risk of developing Parkinson’s Disease and Alzheimer’s were locked.  I was required to read through a long explanation of the meaning and  implications of the test results before I could access them.  It turns out, however, that people seem to be less psychologically devastated by adverse genetic test results than many of the experts anticipated.  For instance, a study published in the New England Journal of Medicine found that “in sample of subjects who completed follow-up after undergoing consumer genomewide testing, such testing did not result in any measurable short-term changes in psychological health, diet or exercise behavior, or use of screening tests.”  

After considering the benefits and risks of direct-to-consumer genetic tests such as 23andMe, it seems that they likely result in more good than harm.  I reckon our federal government’s resources would be better spent taking on public health risks much greater than those posed by 23andMe.

 

 
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Posted by on November 28, 2013 in Uncategorized

 

Benefits of Yoga and Meditation

After a busy, intense day of work at the clinic, I sometimes try to make an early evening yoga class at a nearby studio. It is a relief to empty my mind and focus on performing the poses the instructor sets forth.  

Over time, multiple studies have corroborated my experience of the benefits of yoga and meditation.  As Dr. Andrew Newberg of Thomas Jefferson University Hospital and Medical College writes, 

If you stay in a contemplative state for twenty minutes to an hour, your experiences will tend to feel more real, affecting your nervous system in ways that enhance physical and emotional health.  Antistress hormones and neurochemicals are released throughout the body, as well as pleasure-enhancing and depression-decreasing neurotransmitters like dopamine and serotonin.  Even ten to fifteen minutes of meditation appears to have significantly positive effects on cognition, relaxation, and psychological health, and it has been shown to reduce smoking and binge-drinking behavior.  

One of the pioneers in the study of the health benefits of meditation is Dr. Herbert Benson, Professor at Harvard Medical School.  His book, The Relaxation Response, is a classic and a great introduction to this field.

 

 
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Posted by on November 27, 2013 in Uncategorized