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2011年5月6日星期五

Personal Health: A Thief That Robs the Brain of Language

 

The neurologist he consulted thought Mr. Riedner had suffered a stroke and for three years treated him with cholesterol-lowering medication. But instead of his language ability stabilizing or improving, as should happen following a stroke, it got worse.


A second neurologist concluded after further testing that Mr. Riedner might have a condition called primary progressive aphasia, or P.P.A., a form of dementia affecting the brain’s language center.


Having seen only one other case in his career, the neurologist referred Mr. Riedner and his wife, Mary Beth, to the Cognitive Neurology and Alzheimer’s Disease Center at Northwestern University, whose director, Dr. M. Marsel Mesulam, is perhaps the world’s leading expert on this relatively rare disorder.


P.P.A. is a clinical syndrome, one of several forms of brain disease lost in the medical shadow of their much better known relative Alzheimer’s disease. While hardly as common as Alzheimer’s, P.P.A. is often misdiagnosed, and many patients like Mr. Riedner lose valuable time trying inappropriate and ineffective treatments. Though there is no cure, patients and families can learn ways to minimize the disabilities it causes.


Unlike Alzheimer’s, P.P.A. does not affect memory, at least not initially. It also tends to occur at younger ages, often in the late 50s, and affects twice as many men as women. While symptoms of Alzheimer’s are readily recognized by friends and relatives but not those affected, people with P.P.A. are painfully aware of their struggle to communicate, often long before it is apparent to others.


“Early symptoms are usually very subtle, and patients may be the only ones aware of the problem because they have to work harder to communicate, even though they may not make obvious errors,” said Joseph R. Duffy, head of speech pathology at the Mayo Clinic in Rochester, Minn. “Initially, their communicative errors are like those we all make and may be written off as due to chronic fatigue. But gradually the errors of speech occur with increasing frequency.”


‘Like Being a Parent Again’


The disorder is also commonly misdiagnosed, usually as Alzheimer’s disease or a result of depression or anxiety, Dr. Duffy said in an interview. But while a definitive diagnosis can be made only at autopsy, the results of neuropsychological testing and the patient’s progressive difficulty with communication despite a normal memory can pinpoint P.P.A. as the problem.


As the condition worsens, cognitive difficulties may become apparent. Now seven years into the disorder, Mr. Riedner is having increasing problems performing the tasks of daily living.


“He can no longer punch in the numbers to operate the garage door or the microwave or the remote for the TV,” Mrs. Riedner, his wife of 38 years, said in an interview. “He might open the car window, then not know how to close it. We bought him an iPad, but he can’t learn how to use it.”


New ways of communicating have to be learned, like using gestures or making lists of things to say or do or eat, so that the person can point to them when needed. Unfortunately, sign language doesn’t work because it, too, depends on the region of the brain that is diseased.


“In some ways it’s like being a parent again. He acts in childlike ways sometimes, but he still wants to be himself, an independent adult,” Mrs. Riedner said. “Coping with the problem takes an immense amount of patience on both our parts.”


Mrs. Riedner said the center at Northwestern has been “a lifesaver for us,” a source of support, speech therapy and rehabilitation, help with practical matters like applying for Social Security disability insurance, and tips on how to minimize the inevitable frustrations that can accompany lost language skills.


Dr. Mesulam was the first in modern times to recognize the distinction between P.P.A. and other forms of dementia.


In 1975, as a newly minted neurologist at Beth Israel Hospital in Boston, he became puzzled by a group of patients who seemed to know what they wanted to say but couldn’t string words together in an intelligible sequence. Their communicative problems got progressively worse, although there were no lesions apparent in their brains.


His report in 1982 on six such cases stimulated modern interest in P.P.A. As Dr. Mesulam explained in a retrospective article in the journal Alzheimer Disease and Associated Disorders in the fall of 2007, “The aphasia can interfere with word-finding, object naming, syntax, phonology, morphology, spelling or word comprehension. The progression occurs in the course of years rather than months, and the primary nature of the aphasia is demonstrated by showing that memory for recent events, recognition of familiar faces and objects, reasoning, and basic aspects of comportment are relatively preserved at the initial stages.”


Focus on What Remains


With no therapy available to treat the underlying disease, treatment involves determining which aspects of language are strongest, then providing speech therapy that emphasizes those areas and avoids areas in which patients are weakest, Dr. Mesulam said.


Dr. Duffy said that early intervention is important and should focus on alternative approaches to communication like using a computer, picture icons, or iPhones or iPads that have apps that can talk for a person. Family members are taught how to aid comprehension by communicating simply and clearly: telling patients only one thing at a time, reducing noise and other distractions, and avoiding multitasking.


Family members are also taught coping skills and helped to prepare for the future as the disease progresses, said Darby Morhardt, a social worker at the Northwestern center. “There’s inevitably a grieving process as patients change right before their eyes, but at the same time families want to grasp as much as possible of what remains.”


Patients often are encouraged to develop new hobbies and skills that don’t rely on communication, like woodworking, gardening, fishing, sculpting or painting. Among Northwestern’s patients is one who began breeding pigeons and another who started judging dog races.


Unfortunately, if patients live long enough, other deficits — including those involving memory and cognitive abilities, and motor problems resembling symptoms of Parkinson’s disease — often become apparent, as is now happening to Mr. Riedner.


Like Alzheimer’s disease, P.P.A. shortens life expectancy: The average age of death is 67. Ms. Morhardt said it’s important for patients and their families not to delay getting financial matters in order. Many would be wise to consult a lawyer who specializes in elder law, she said.


This article has been revised to reflect the following correction:


Correction: May 5, 2011


The Personal Health column on Tuesday, about primary progressive aphasia, a type of dementia that affects the brain’s language center, misspelled the hometown of Steve Riedner, who struggled with symptoms for years before the disease was correctly diagnosed. It is Schaumburg, Ill., not Schaumberg.


 

2011年4月16日星期六

Magazine Preview: Do Cellphones Cause Brain Cancer?

  Bruce Gilden/Magnum, for The New York Times

On Jan. 21, 1993, the television talk-show host Larry King featured an unexpected guest on his program. It was the evening after Inauguration Day in Washington, and the television audience tuned in expecting political commentary. But King turned, instead, to a young man from Florida, David Reynard, who had filed a tort claim against the cellphone manufacturer NEC and the carrier GTE Mobilnet, claiming that radiation from their phones caused or accelerated the growth of a brain tumor in his wife.


“The tumor was exactly in the pattern of the antenna,” Reynard told King. In 1989, Susan Elen Reynard, then 31, was told she had a malignant astrocytoma, a brain cancer that occurs in about 6,000 adults in America each year. To David Reynard, the shape and size of Susan’s tumor — a hazy line swerving from the left side of her midbrain to the hindbrain — uncannily resembled a malignant shadow of the phone (but tumors, like clouds, can assume the shapes of our imaginations). Suzy, as she was known, held her phone at precisely that angle against her left ear, her husband said. Reynard underwent surgery for her cancer but to little effect. She died in 1992, just short of her 34th birthday. David was convinced that high doses of radiation from the cellphone was the cause.


Reynard v. NEC — the first tort suit in the United States to claim a link between phone radiation and brain cancer — illustrated one of the most complex conceptual problems in cancer epidemiology. In principle, a risk factor and cancer can intersect in three ways. The first is arguably the simplest. When a rare form of cancer is associated with a rare exposure, the link between the risk and the cancer stands out starkly. The juxtaposition of the rare on the rare is like a statistical lunar eclipse, and the association can often be discerned accurately by observation alone. The discipline of cancer epidemiology originated in one such a confluence: in 1775, a London surgeon, Sir Percivall Pott, discovered that scrotal cancer was much more common in chimney sweeps than in the general population. The link between an unusual malignancy and an uncommon profession was so striking that Pott did not even need statistics to prove the association. Pott thus discovered one of the first clear links between an environmental substance — a “carcinogen” — and a particular subtype of cancer.


The opposite phenomenon occurs when a common exposure is associated with a common form of cancer: the association, rather than popping out, disappears into the background, like white noise. This peculiar form of a statistical vanishing act occurred famously with tobacco smoking and lung cancer. In the mid-1930s, smoking was becoming so common and lung cancer so prevalent that it was often impossible to definitively discern a statistical link between the two. Researchers wondered whether the intersection of the two phenomena was causal or accidental. Asked about the strikingly concomitant increases in lung cancer and smoking rates in the 1930s, Evarts Graham, a surgeon, countered dismissively that “the sale of nylon stockings” had also increased. Tobacco thus became the nylon stockings of cancer epidemiology — invisible as a carcinogen to many researchers, until it was later identified as a major cause of cancer through careful clinical studies in the 1950s and 1960s.


But the most complex and most publicly contentious intersection between a risk factor and cancer often occurs in the third instance, when a common exposure is associated with a rare form of cancer. This is cancer epidemiology’s toughest conundrum. The rarity of the cancer provokes a desperate and often corrosive search for a cause (“why, of all people, did I get an astrocytoma?” Susan Reynard must have asked herself). And when patients with brain tumors happen to share a common exposure — in this case, cellphones — the line between cause and coincidence begins to blur. The association does not stand out nor does it disappear into statistical white noise. Instead, it remains suspended, like some sort of peculiar optical illusion that is blurry to some and all too clear to others. (A similarly corrosive intersection of a rare illness, a common exposure and the desperate search for a cause occurred recently in the saga of autism and vaccination. Vaccines are nearly universal, and autism is relatively rare — and many parents, searching to explain why their children became autistic, lunged toward a common culprit: childhood vaccination. An avalanche of panic ensued. It took years of carefully performed clinical trials to finally disprove the link.)


The Florida Circuit Court that heard Reynard v. NEC was quick to discern these complexities. It empathized with David Reynard’s search for a tangible cause for his wife’s cancer. But it acknowledged that too little was known about such cases; “the uncertainty of the evidence . . . the speculative scientific hypotheses and [incomplete] epidemiological studies” made it impossible to untangle cause from coincidence. David Reynard’s claim was rejected in the spring of 1995, three years after it was originally filed. What was needed, the court said, was much deeper and more comprehensive knowledge about cellphones, brain cancer and of the possible intersection of the two.


Allow, then, a thought experiment: what if Susan Reynard was given a diagnosis of astrocytoma in 2011 — but this time, we armed her with the most omniscient of lawyers, the most cutting--edge epidemiological information, the most powerful scientific evidence? Nineteen years and several billion cellphone users later, if Reynard were to reappear in court, what would we now know about a possible link between cellphones and her cancer?


To answer these questions, we need to begin with a more fundamental question: How do we know that anything causes cancer?


The crudest method to capture a carcinogen’s imprint in a real human population is a large-scale population survey. If a cancer-causing agent increases the incidence of a particular cancer in a population, say tobacco smoking and lung cancer, then the overall incidence of that cancer will rise. That statement sounds simple enough — to find a carcinogen’s shadow, follow the trend in cancer incidence — but there are some fundamental factors that make the task complicated.


Siddhartha Mukherjee (smukherj2011@gmail.com) is an assistant professor of medicine in the division of medical oncology at Columbia University. He is the author of “Emperor of All Maladies: A Biography of Cancer.” Editor: Ilena Silverman (i.silverman-MagGroup@nytimes.com).