Friday, June 17, 2011

brainSCANr - Alzheimer's disease

The Brain Systems, Connections, Associations, and Network Relationships (a phrase with more words than strictly necessary in order to bootstrap a good acronym) assumes that somewhere in all the chaos and noise of the more than 20 million papers on PubMed, there must be some order and rationality.

To that end, we have created a dictionary of hundreds of brain region names, cognitive and behavioral functions, and diseases (and their synonyms!) to find how often any two phrases co-occur in the scientific literature. We assume that the more often two terms occur together (at the exclusion of those words by themselves, without each other), the more likely they are to be associated.

Are there problems with this assumption? Yes, but we think you'll like the results anyway. Obviously the database is limited to the words and phrases with which we have populated it. We also assume that when words co-occur in a paper, that relationship is a positive one (i.e., brain areas A and B are connected, as opposed to not connected). Luckily, there is a positive publication bias in the peer-reviewed biomedical sciences that we can leverage to our benefit (hooray biases)! Furthermore, we cannot dissociate English homographs; thus, a search for the phrase "rhythm" (to ascertain the brain regions associated with musical rhythm) gives the strongest association with the suprachiasmatic nucleus (that is, for circadian rhythms!)

Despite these limitations, we believe we have created a powerful visualization tool that will speed research and education, and hopefully allow for the discovery of new, previously unforeseen connections between brain, behavior, and disease.'s disease

The Big Business of Synthetic Highs - BusinessWeek

It's a Friday afternoon in April, and Wesley Upchurch, the 24-year-old owner of Pandora Potpourri, has arrived at his factory to fill some last-minute orders for the weekend. The factory is a cramped, unmarked garage bay adjoining an auto body shop in Columbia, Mo. What Upchurch and his one full-time employee, 21-year-old Jay Harness, are making is debatable, at least in their eyes. The finished product looks like crushed grass, comes in three-gram (.11ounce) packets, and sells for about $13 wholesale. Its key ingredient is a synthetic cannabinoid that mimics tetrahydrocannabinol (THC), the active ingredient in marijuana. Upchurch, however, insists his product is incense. "There are rogue players in this industry that make the business look bad for everyone," Upchurch says. "We don't want people smoking this."

From the outside the place looks abandoned. The only sign of life is a lone security camera. Inside, two flags hang above a makeshift assembly line. One shows a coiled snake and reads "Don't Tread On Me." The other has a peace symbol. The work space consists of a long, foldout table containing a pile of lustrous, green vegetation, a pocket-calculator-size electronic scale, a stack of reflective, hot-pink Mylar foil packets, and a heat sealer. Each packet has the brand name, Bombay Breeze, and is decorated with a psychedelic logo featuring a cartoon elephant meditating among abstract-looking coils of smoke and stars.

Upchurch supervises as Harness weighs out portions of the crushed foliage, dumps it into a packet, and slides the top through the heating machine to create an airtight, tamper-proof seal. He finishes about a dozen in 10 minutes, topping off what they will need for their deliveries: two shipments of more than 1,000 packets each. Upchurch points to a disclaimer near the bottom right-hand corner of each package that reads, in all caps: "NOT FOR CONSUMPTION." Says Upchurch: "That's to discourage abuse."

His protests and disclaimers to the contrary, Pandora is getting smoked—it's being packed into bongs and reviewed on sites such as YouTube (GOOG)—for its ability to alter the mind. Like many others, Upchurch is repackaging experimental medical chemicals for mainstream store shelves, most often with some clever double-entendre in the branding. He says he sells about 41,000 packets a month, delivering directly to 50 stores around the country and shipping the rest to five other wholesalers, some of whom use Pandora's products to create their own brands. Upchurch says he ships mostly in bulk orders for larger discounts. He projects his company will earn $2.5 million in revenue with $500,000 in profits this year, depending on what federal and state laws pass. "I think my business model is based less on charts than it is on guts, or something," he says.

"Incense" such as Upchurch's, along with "bath salts" and even "toilet bowl cleaner," have been popping up at gas stations, convenience stores, "coffee shops" that don't sell much coffee, and adult novelty stores. Today, Upchurch's shipments—he uses UPS (UPS)—are headed to places called Jim's Party Cabin in Junction City, Kan., and the Venus Adult Superstore, in Texarkana, Ark. Instate, Upchurch sells to Coffee Wonk, a coffee shop in downtown Kansas City, Mo. There, 28-year-old owner Micah Riggs writes the names of his offerings in multiple colors on a dry erase board near the register. The packets themselves are kept beneath the counter. While Riggs doesn't mind his customers talking about how they will use the incense, he's as circumspect about what he is actually selling as Upchurch. Nearly everything he says is in code. He'll say things like, "Is this your first foray?" and "There are different potencies of aroma."

Customers report different reasons for trying Riggs's products. Some say they need to pass a drug test; synthetics do not show up in standard tests. Others are businessmen in khakis who like the idea of buying from someone they trust. Riggs claims to sell mostly to the military, soccer moms, teachers, and lots of firefighters. "I don't tell people what to do with it," Riggs says. "This is a marketer's dream. I underpromise and it overdelivers."

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Thursday, June 16, 2011

New OxyContin Formula Is Said to Curb Abuses -

BROCKTON, Mass. — Michael Capece had been snorting OxyContin for five years when a new version of the drug, intended to deter such abuse, hit the market last summer. The reformulated pills are harder to crush, turning instead into a gummy substance that cannot be easily snorted, injected or chewed.

Instructed by his dealer, Mr. Capece, 21, tried microwaving one of the new pills, then sniffing up the burnt remains. Other addicts have tried to defeat the new formula by freezing, baking or soaking the pills in solvents ranging from soda to acetone. Many are ending up frustrated.

"It's too much work," said Mr. Capece who entered a rehab program here last month. "It wasn't anything I enjoyed."

A powerful narcotic meant for cancer patients and others with searing pain, OxyContin is designed to slowly release its active ingredient, oxycodone, over 12 hours. But after it was introduced in 1996, drug abusers quickly discovered that chewing an OxyContin tablet — or crushing one and snorting the powder, or injecting it with a needle — produced an instant high as powerful as heroin. It has been blamed for waves of addiction that have ravaged certain regions of the country, and has been a factor in many overdose deaths.

Purdue Pharma, the maker of OxyContin, may have succeeded for now in reducing illicit demand for its reformulated drug. But in several dozen interviews over the last few months, drug abuse experts, law enforcement officials and addicts said the reformulation had only driven up interest for other narcotics.

Demand appears especially high for pure oxycodone pills that come in a 30-milligram dose, often called "Perc 30s" or "Roxies" on the street. Opana, a time-release painkiller similar to OxyContin that has been on the market for five years, is showing up increasingly in police reports and has been blamed for a rash of overdose deaths. And heroin use has jumped sharply in many regions, according to rehab centers and the police.

"It's just a matter of switching," said John Burke, commander of the drug task force in Warren County, Ohio, and president of the National Association of Drug Diversion Investigators. "If I'm an addict, I'm going to find a drug that works."

Mr. Burke said abuse of other oxycodone drugs was already growing before OxyContin was reformulated last August, partly because the other drugs are cheaper and because OxyContin had become harder to find on the street. Many doctors had stopped prescribing it because of its stigma and switched to other oxycodone drugs, Mr. Burke said.

Raymond V. Tamasi, president and chief executive of Gosnold on Cape Cod, a treatment center, said he had noticed that addicts switch initially to the Perc 30s.

"But eventually people make that progression from the pills to what appears to be a more economical high, which is heroin," Mr. Tamasi said.

Prices vary, but 30-milligram oxycodone tablets generally sell on the street for $20 to $30 each, according to addicts and law enforcement officials. The old OxyContin sold for as much as $80 per 80-milligram pill. Several recovering addicts in Massachusetts said an 80-milligram tablet of the reformulated version, called OxyContin OP, costs about $40.

"You don't make any money selling the OPs," said James Moore, 28, who said he stopped selling and snorting OxyContin and moved on to heroin after the new version came out last year.

Mr. Moore, who said he used to snort as many as 10 OxyContin pills daily, was arrested in November for selling heroin and now lives at a halfway house in East Boston. Addicts can still get high from swallowing the new OxyContin pills, he said, but most prefer the immediate rush delivered by snorting or injecting the powder.

Outside of OxyContin, which comes in doses as high as 80 milligrams, the 30-milligram dose is the highest available for oxycodone, which is why addicts covet it.

Some addicts are reporting an even more powerful high from Opana, a time-release opiate painkiller whose active ingredient is oxymorphone. In Louisville, Ky., there have been at least 14 deaths this year involving Opana, according to the Jefferson County coroner's office.

Purdue Pharma should have reformulated OxyContin sooner, said Steven Tolman, a state senator in Massachusetts who led a commission that investigated OxyContin abuse. The company asked the Food and Drug Administration to approve the new version for sale in November 2007; it won the approval in April 2010. It is the first painkiller reformulated to deter abuse, according to the F.D.A., which is now studying several proposed reformulations of other opiate drugs.

"It should not clear their conscience," Mr. Tolman said of the change. "These people are scientists. Why didn't they do this years ago?"

Not everyone is convinced that the days of abusing OxyContin are over. The F.D.A. is requiring Purdue Pharma to conduct clinical trials before it can claim that the new version is less abuse-prone. Though many addicts appear frustrated by the reformulation, Dr. Mark Publicker, an addiction medicine specialist at Mercy Recovery Center in Westbrook, Me., said he was "absolutely certain" that people would figure out how to abuse the new OxyContin.

"I like to think of them as drug addict scientists in white lab coats," he said, pointing to Web sites where drug abusers debate various ways of trying to defeat the new formulation.

Libby Holman, a Purdue Pharma spokeswoman, said that based on initial data and reports, the company is "cautiously optimistic" that the reformulation will eventually prove less susceptible to abuse. But long-term studies will be necessary, she said in an e-mail, adding, "It is still too early to make any conclusions about the product's impact on abuse and misuse in real-world settings."

The company has initiated eight epidemiological studies and will report updates to the F.D.A., which approved their design, Ms. Holman said. Meanwhile, the new OxyContin pills have won some unflattering nicknames, said Dr. Ronald Bugaoan, director of psychiatric services at the High Point Treatment Center in Brockton.

"They call them gummies because when you chew them up they get stuck between your teeth," he said. "They call them jellynoses because when you try to snort it up they get stuck. They cake in the nose."

Mr. Moore, the recovering addict in East Boston, said that it was possible to snort the new OxyContin but that it took about an hour to break it down.

"It's like doing a science project," he said, "sitting there with a scraper, a knife, a razor blade, like it's a frog or something."

Wednesday, June 15, 2011

More physicians leaving private practices -

A survey by Accenture indicates more U.S. physicians are selling their private practices to work at larger healthcare systems.

By 2013, less than one-third of U.S. physicians are expected to remain in private practice and patients may increasingly find that being treated by physicians in private, small practice settings may be a thing of the past.

"Health reform is challenging the entire system to deliver improved care through insight driven health," Kristin Ficery, a senior executive at Accenture Health, says in a statement.

Physicians tell the survey that they are increasingly attracted to the benefits offered by hospital-based employment opportunities, which include: relief from administrative responsibilities; greater access to leading healthcare information technology tools, facilities and equipment; and a more manageable work week and stability.

"We see an increasing number of physicians leaving private practice to join hospital systems, which will force all stakeholders to revise and refine their business models, product offerings and service strategies," Ficery says.

Accenture conducted in-person and phone interviews with hospital executives and industry stakeholders between September to November last year and the analysis was completed in 2011. private-practices/UPI-84191308100918/?spt=hs∨=hn

My first time: humour for medical professionals | Stitches Magazine

As a medical student, my first clerkship was obstetrics at the Royal Victoria Hospital in Montreal. I recall eagerly donning a mask and gown as a woman in labour was wheeled into the delivery room. I timidly proceeded to take my place behind the obstetrician, resident and intern, craning to get a good view.

However, to my disappointment, I was directed to the head of the table. A nurse told me to look in the mirror to observe the birth. I felt relieved, assuming that the medical students must be so placed in order not to get in the way.

Then I was instructed to hold the patient's hand. I felt a little uncomfortable as I complied, but I supposed this was a lesson in bedside manners. The patient seemed reassured as she firmly squeezed my hand.

After the birth of the baby, I was asked if I wanted to cut the umbilical cord. I was delighted, thinking this the kind of handson experience that medical students got from their rotations in the hospitals.

After successfully completing the procedure, I was told to kiss the mother! I stood frozen in disbelief as everyone encouraged me to proceed. Extremely embarrassed, I brought my masked face several inches from the patient's cheek before I escaped outside feeling totally dumfounded.

In the corridor, a man in mask and gown was waiting nervously. "Can I go in now?" he asked me, and I suddenly realized that everyone, including the patient, had mistaken me for the baby's father.

Tuesday, June 14, 2011

Aging: To Treat, or Not to Treat? - American Scientist

The 20th century brought both profound suffering and profound relief to people around the world. On the one hand, it produced political lunacy, war and mass murder on an unprecedented scale. But there were also extraordinary gains—not least in public health, medicine and food production. In the developed world, we no longer live in constant fear of infectious disease. Furthermore, a Malthusian catastrophe of global population growth exceeding food production—a terrifying prospect predicted first in the 18th century—did not materialize. This is largely due to a steep decline in birth rates, for which we can thank the education, emancipation and rationality of women. Most people in the developed world can now expect to live long lives.

Yet, as too often happens, the solution of one problem spawns others. Because we are having fewer children and living longer, the developed world is now filling up with old people. In Japan, for example, where the population is aging particularly quickly, the ratio of people less than 20 years old to those over 65 is plummeting, from 9.3 in 1950 to a predicted 0.59 in 2025. In Europe and the United States, we see ever more bald and grey heads on streets and in parks and shopping malls. Although this is something to celebrate, old age unfortunately has myriad ways of making us ill. It brings cardiovascular disease that leads to heart attacks and strokes; neurodegenerative diseases such as Alzheimer's and Parkinson's that erode the self; and macular degeneration, which blinds. And, of course, there is cancer. Aging has been described as the greatest of all carcinogens. Like the pandemic of obesity, the increasing number of people living long enough to experience these illnesses is, in some ways, a side effect of progress. Now we face this challenging question: Should we attack the underlying cause of this suffering? Should we try to "cure" aging?

I am a scientist working in the growing field of biogerontology—the biology of aging. The cause of aging remains one of the great unsolved scientific mysteries. Still, the past decade has brought real progress in our understanding, raising the prospect that treatments might one day be feasible. Yet aging is not just another disease. And the prospect of treating aging is extraordinary in terms of the potential impact on the human condition. So, would it be ethical to try to treat it?

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First placebo-controlled polypill study |

Sydney, Australia - The first randomized, placebo-controlled study of a polypill has suggested that use of such a product in primary prevention could bring about a halving of heart disease and stroke events, the authors say.

While the authors conclude that a polypill such as this is a potentially highly cost-effective strategy that could alone achieve most of World Health Organization's goals for reducing noncommunicable disease, others see it as a step backward, saying it represents a "dumbing down" of medical practice.

The current study, published online May 25, 2011 in PLoS One, involved 378 individuals without an indication for any component of the polypill but who had an estimated five-year cardiovascular disease risk over 7.5%, determined by the Framingham risk function using data on age, gender, blood pressure, total cholesterol, HDL cholesterol, diabetes status, and cigarette smoking status. They were randomized to the polypill containing aspirin 75 mg, lisinopril 10 mg,hydrochlorothiazide 12.5 mg, and simvastatin 20 mg or to placebo. Results showed that the polypill was associated with a 9.9-mm-Hg drop in systolic blood pressure and a 0.8-mmol/L reduction in LDL cholesterol over a 12-week treatment period.

Adverse effects occurred in 58% of the polypill group vs 42% of the placebo patients, with 23% of the polypill group discontinuing therapy vs 18% of the placebo group.

The authors estimate that if individuals stayed on therapy long term, these effects would translate into an approximate 60% reduction in heart disease and ischemic stroke risk, little overall effect on hemorrhagic stroke risk (the beneficial effects of blood-pressure lowering balancing out the adverse effects of aspirin), and a 50% increase in the risk of extracranial bleeding.

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Colleagues tarred by accusations of plagiarism against U of A dean

EDMONTON — Accusations that the dean of the University of Alberta's medical school plagiarized a graduation speech casts a pall on all his colleagues, one professor says.

"My colleagues are disturbed. It casts all of us in a bad light," John Church, who teaches health policy and political ethics at the U of A, said Monday.

"It undermines the integrity of the university when these things happen. This isn't just someone from the rank and file."

Students publicly complained on the weekend about Dr. Philip Baker's after-dinner speech to graduates Friday night. They said the speech lifted passages word-for-word from one given by Dr. Atul Gawande at Stanford University in 2010 and later published in The New Yorker.

Some students said they searched the speech on smartphones and were able to follow along as Baker spoke.

Baker apologized Sunday, sending emails to students and his colleagues, admitting the theme and much of the content was the same as Gawande's speech. That speech "inspired me and resonated with my experiences," he wrote.

University officials are investigating and have asked for a copy of the speech he delivered.

Even if Baker only borrowed ideas and the structure — not large chunks verbatim, as the students allege — he could be guilty of plagiarism, Church said.

The only way to judge plagiarism is to compare the two speeches side by side. Church warns his students before every course he teaches, "when in doubt, reference the source."

Gawande declined to comment Monday. His speech addressed the daunting task of being a doctor in a time of radical transition and increasing complexity.

It will take humility, Gawande said.

That theme was "overwhelmingly reinforced," said Baker, in his written apology to students.

As a dean, Baker plays a key role judging students accused of plagiarism.

"These are serious allegations and the University of Alberta will treat them as such," university president Indira Samarasekera said in a written statement Monday.

"Academic integrity is at the heart of this university and must continue to be so. We will undertake our examination within a fair process and with due diligence. As would be the case with any such allegations, a thorough review will be conducted under the procedures of the research and scholarship integrity policy and/or the ethical conduct and safe disclosure policy."

University policy states under no circumstance can a student pass off someone else's words, ideas, images or data as their own work in academic writing or in a presentation. Students who do so can be expelled.

University policy also requires researchers and scholars to recognize all collaborators and source other authors in their work. It states misrepresentation of material facts is considered fraud and the disciplinary action could include termination and prosecution.

News of Baker's apology and speech spread quickly within the U of A.

"Ralph Klein was one thing, but a university dean is quite another," said Jeremy Richards, an earth and atmospheric science professor who blogs regularly about university affairs. He was referring to when the former premier was accused of using someone else's ideas in his own student paper without proper attribution.

"How will I be able to look my students in the eye next fall and tell them that plagiarism is the cardinal sin of academia?" Richards asked in an email. "I hope the university's administration acts quickly and appropriately or it will reflect very badly on our institution."

Outside observers have called for Baker to resign.

"Suppose a medical student stood before Dr. Baker charged with plagiarism? One would rightly expect dean Baker to investigate thoroughly and judge the student accordingly," Dr. Brian Goldman wrote on his blog, Dr. Brian's Side of the Gurney. Goldman is a Toronto-based physician and host of the CBC radio program White Coat, Black Art.

He called for Baker's resignation if the allegations against him are upheld.

"If dean Baker gets off, then the door to plagiarism at the University of Alberta will be flung wide open. 'I'll have what he's having,' future plagiarists will say. Therefore, if these allegations against dean Baker are true, he will have no choice but to resign. The deanery is no place for plagiarists, no (matter) how accomplished they are."

Deb Hammacher, spokeswoman for the university, said the institution won't "act in a hasty manner because of what some members of the public would like us to do. Somebody's reputation is a serious thing."

In an email sent to the Students' Union, the university's vice-president of media relations, Debra Pozega Osburn, assured students that the school is taking the allegations seriously.

"Academic integrity is at the heart of the institution," she wrote.

Emerson Csorba, vice-president academic for the undergraduate Students' Union, said he trusts the university to handle the situation.

It was a hot topic for students on campus for convocation Monday, Csorba said. "This event should not overshadow the 2011 school of medicine graduates, as they have come a long way in earning this degree."

The Velluvial Matrix - Stanford Medical School Commencement - Atul Gawande

The Velluvial Matrix 

Stanford Medical School Commencement 

Atul Gawande 

June 12, 2010 

Greetings to the graduating class of 2010. Thank you for inviting me back to this gorgeous place where I'd gone to college and worked in this school's laboratories—and even, in my sophomore dormitory, met my wife. But most of all thank you for letting me be part of this special occasion. 

To take your place in those folding chairs, you have trod a long road. Many of you have worked for four solid years—or five, or six, or nine. And we are here to declare that, as of today, the twelfth of June, 2010, you officially know enough stuff to be called a graduate of the Stanford School of Medicine. You are Doctors of Medicine, Doctors of Philosophy, Masters of Science. It's been certified. Each of you is now an expert. Congratulations. 

So why—in your heart of hearts—does it not quite feel that way? 

The experience of a medical and scientific education is transformational. It is like moving to a new country. At first, you don't know the language, let alone the customs and concepts. But then, almost imperceptibly, that changes. Half the words you now routinely use, you did not know existed when you started: words like arterial blood gas, nasogastric tube, microarray, logistic regression, NMDA receptor, velluvial matrix. 

Okay, I made that last one up. But the velluvial matrix sounds like something you should know about, doesn't it? And that's the problem. I will let you in on a little secret. You never stop wondering if there is a velluvial matrix you should know about. 

Since I graduated from medical school, my family and friends have had their share of medical issues arise, just as you and your family will. And inevitably, they turn to the medical graduate in the house for advice and explanation. I remember one time when a friend came with a question. 

"You're a doctor now," he said. "So tell me: where exactly is the solar plexus?" 

I was stumped. It was not anywhere in the textbooks. 

"I don't know," I finally confessed. 

"What kind of doctor are you?" he said. 

I didn't feel much better equipped when my wife had two miscarriages, or our first child was born with part of his aorta missing and we had to figure out what to do, or when my daughter had a fall with a dislocated elbow that I failed to recognize, or when my wife tore a ligament in her wrist that I'd never heard of—her velluvial matrix, I think it was. 

This is a deeper, more fundamental problem than we acknowledge. The truth is that the volume and complexity of the knowledge we need to master in medicine and science has grown exponentially beyond our capacity as individuals. Worse, the fear is that the knowledge has grown beyond our capacity as a society. When we talk about the uncontrollable explosion in the costs of health care in America, for instance, about the reality that we in medicine are gradually bankrupting the country, we're not talking about a problem rooted in economics. We're talking about a problem rooted in scientific complexity. 

Half a century ago, medicine was neither costly nor effective. Since then, however, science has combated our ignorance. It has enumerated and identified, according to the international disease classification system, more than 13,600 diagnoses, 13,600 different ways our bodies can fail. And for each, we've discovered beneficial remedies—remedies that can reduce suffering, extend lives, and sometimes stop a disease all together. But those remedies now include more than 6,000 drugs and 4,000 medical and surgical procedures—and growing. Our job in medicine is make sure all of this capability is deployed, town by town, in the right way at the right time, without harm or waste of resources, for every person alive. And we're struggling. There is no industry in the world with 13,600 different service lines to deliver. 

It should be no wonder that you have not mastered the understanding of them all. No one ever will. That's why we as doctors and scientists have become ever more finely specialized and super-specialized. If I can't handle 13,600 diagnoses, well maybe there are fifty of them I can handle—or just one I might focus my research upon. The result, however, is that we each find ourselves to be specialists worried almost exclusively about our particular niche and not the larger question of whether we as a group are making the whole system of care better for people. 

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New iPhone app for migraine sufferers

A new application for the iPhone has been launched that is aimed at helping migraine sufferers to document symptoms.

The new app, called the Migraine Notebook, will enable those who suffer with severe and frequent migraines to log the frequency and severity of their migraines, as well as details such as when they occur, how long they last for and what the circumstances were surrounding the onset. Patients will also be able to state when they took their medication and whether a repeat dose was required.

Dr Merle Diamond, of the Diamond Headache Centre in Chicago, said: One of the biggest issues in medicine is how you communicate with your doctor.

This app gives us a window of communication which I think is really important in treating headaches. For example, it allows me to prepare questions about how they are using the medication.

It is hoped that the app will help patients and doctors to communicate more efficiently which will help to prescribe treatment and give advice on minimising the occurrence of migraines.

Sunday, June 12, 2011

Don’t Quit This Day Job -

I'm a doctor and a mother of four, and I've always practiced medicine full time. When I took my board exams in 1987, female doctors were still uncommon, and we were determined to work as hard as any of the men.

Today, however, increasing numbers of doctors — mostly women — decide to work part time or leave the profession. Since 2005 the part-time physician workforce has expanded by 62 percent, according to recent survey data from the American Medical Group Association, with nearly 4 in 10 female doctors between the ages of 35 and 44 reporting in 2010 that they worked part time.

This may seem like a personal decision, but it has serious consequences for patients and the public.

Medical education is supported by federal and state tax money both at the university level — student tuition doesn't come close to covering the schools' costs — and at the teaching hospitals where residents are trained. So if doctors aren't making full use of their training, taxpayers are losing their investment. With a growing shortage of doctors in America, we can no longer afford to continue training doctors who don't spend their careers in the full-time practice of medicine.

It isn't fashionable (and certainly isn't politically correct) to criticize "work-life balance" or part-time employment options. How can anyone deny people the right to change their minds about a career path and choose to spend more time with their families? I have great respect for stay-at-home parents, and I think it's fine if journalists or chefs or lawyers choose to work part time or quit their jobs altogether. But it's different for doctors. Someone needs to take care of the patients.

The Association of American Medical Colleges estimates that, 15 years from now, with the ranks of insured patients expanding, we will face a shortage of up to 150,000 doctors. As many doctors near retirement and aging baby boomers need more and more medical care, the shortage gets worse each year.

The decline in doctors' pay is part of the problem. As we look at Medicare and Medicaid spending cuts, we need to be careful not to drive the best of the next generation away from medicine and into, say, investment banking.

But the productivity of the doctors currently practicing is also an important factor. About 30 percent of doctors in the United States are female, and women received 48 percent of the medical degrees awarded in 2010. But their productivity doesn't match that of men. In a 2006 survey by the American Medical Association and the Association of American Medical Colleges, even full-time female doctors reported working on average 4.5 fewer hours each week and seeing fewer patients than their male colleagues. The American Academy of Pediatrics estimates that 71 percent of female pediatricians take extended leave at some point — five times higher than the percentage for male pediatricians.

This gap is especially problematic because women are more likely to go into primary care fields — where the doctor shortage is most pronounced — than men are. Today 53 percent of family practice residents, 63 percent of pediatric residents and nearly 80 percent of obstetrics and gynecology residents are female. In the low-income areas that lack primary and prenatal care, there are more emergency room visits, more preventable hospitalizations and more patients who die of treatable conditions. Foreign doctors emigrate to the United States to help fill these positions, but this drains their native countries of desperately needed medical care.

If medical training were available in infinite supply, it wouldn't matter how many doctors worked part time or quit, because there would always be new graduates to fill their spots. But medical schools can only afford to accept a fraction of the students who apply.

An even tighter bottleneck exists at the level of residency training. Residents don't pay tuition; they are paid to work at teaching hospitals. Their salaries are supported by Medicare, which pays teaching hospitals about $9 billion a year for resident salaries and teaching costs as well as patient care.

In 1997, Congress imposed a cap on how many medical residencies the government could subsidize as part of the Balanced Budget Act. Last year, the Senate failed to pass an amendment to the health care bill that would have created thousands of new residency positions. Even if American medical schools could double their graduating classes, there wouldn't be additional residency positions for the new doctors. Federal and state financing to expand medical education will be hard to find in today's economic and political climate.

We often hear the argument that nurse practitioners, nurse anesthetists and physician assistants can stand in for doctors and provide cheaper care. But when critical decisions must be made, patients want a fully qualified doctor to lead the health care team.

Policy makers could encourage more doctors to stay in the profession by reforming the malpractice system to protect them from frivolous lawsuits, safeguarding their pay from further Medicare cuts and lightening the burden of bureaucratic regulations and paperwork. And in a perfect world, hospitals and clinics could keep more female doctors working full time by setting up child care centers — with long operating hours — on site. 

In the meantime, we can only depend on doctors' own commitment to the profession.

Students who aspire to go to medical school should think about the consequences if they decide to work part time or leave clinical medicine. It's fair to ask them — women especially — to consider the conflicting demands that medicine and parenthood make before they accept (and deny to others) sought-after positions in medical school and residency. They must understand that medical education is a privilege, not an entitlement, and it confers a real moral obligation to serve.

I recently spoke with a college student who asked me if anesthesiology is a good field for women. She didn't want to hear that my days are unpredictable because serious operations can take a long time and emergency surgery often needs to be done at night. What she really wanted to know was if my working life was consistent with her rosy vision of limited work hours and raising children. I doubt that she welcomed my parting advice: If you want to be a doctor, be a doctor.

You can't have it all. I never took cupcakes to my children's homerooms or drove carpool, but I read a lot of bedtime stories and made it to soccer games and school plays. I've ridden roller coasters with my son, danced at my oldest daughter's wedding and rocked my first grandson to sleep. Along the way, I've worked full days and many nights, and brought a lot of very sick patients through long, difficult operations.

Patients need doctors to take care of them. Medicine shouldn't be a part-time interest to be set aside if it becomes inconvenient; it deserves to be a life's work.