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COLUMN ONE : The Search for Relief From Pain : Long ignored, patients’ suffering gets increased medical attention. Doctors are learning about treatments as researchers overturn myths.

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TIMES STAFF WRITER

It is the leading reason for seeking a doctor’s care and for taking medications. But it is also the least understood of human maladies, rarely considered a significant health problem in its own right.

Now, the study of pain is coming into its own as one of the most unusual specialties in medicine. A small but growing number of doctors and researchers are discovering just how little is known about pain and the harm it can cause. They are pursuing new avenues of research, opening treatment clinics and launching organizations to overturn long-held myths.

Already these pain specialists have learned that physical suffering is far more complex than once thought, and that the number of under-treated cases of pain is far more vast.

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More than 60% of newly diagnosed cancer patients are in such agony that medical intervention is required for their pain, but doses of pain medication are inadequate in half of them.

As many as two-thirds of all adults operated on in U.S. hospitals receive insufficient pain relief. With children, the problem is worse. After surgery, many youngsters are given little, if any, pain medication. Until only four or five years ago, almost all premature babies and many full-term newborns were operated on without benefit of any anesthesia whatsoever.

Many health care professionals still believe newborns are incapable of feeling pain; they assume the elderly have to endure it as a natural part of the aging process. Some believe pain is good for a person, that it builds character and stronger bodies.

None of these assumptions is correct.

Nor is it true, as has long been assumed, that the most potent painkillers are addictive. Recent studies have shown that even powerful narcotics such as morphine are rarely, if ever, addictive when taken for real pain.

“Doctors don’t know how to treat physical suffering because they are never taught to think of pain as anything but a symptom of something else,” said Dr. John J. Bonica, founder of the country’s first pain clinic at the University of Washington. “Pain has never been part of the standard medical school curriculum. . . . It is rarely even mentioned in medical textbooks. Aside from anesthesiologists, whose practice has largely been confined to the operating room, almost no one has been trained in the subject of pain management.”

John C. Liebeskind, professor of psychology at UCLA and a pioneer in pain-relief research, recalls having heard “the dean of a major medical school say that pain does not kill, therefore presumably it is not worth studying--and sometimes not even worth treating.”

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In fact, Liebeskind insists, “pain can kill.”

Recent hospital studies have concluded that acute pain slows recovery and causes a host of medical complications. Severe pain makes breathing difficult and puts stress on the heart and circulatory system. There is also evidence that pain can suppress the immune system, which in turn may allow diseases to take hold.

When pain persists, it can produce dramatic personality changes and permanently alter family and work relations.

“Pain is never good. It is a warning signal of something bad,” said Tony L. Yaksh, director of the Laboratory of Anesthesiology Research at UC San Diego. “If the warning system goes awry . . . or if it is not shut down soon enough and the pain is allowed to persist, it can wreak havoc” on a human body.

The first systematic effort to treat pain began in the early 1960s with Bonica’s creation of a multidisciplinary pain clinic in Seattle. Today there are more than 1,000 pain clinics throughout the United States, 68 in California alone.

Pain experts have since organized their own professional societies--among them, the International Assn. for the Study of Pain and the American Pain Society. These experts have begun to publish new medical journals--Pain; the Clinical Journal of Pain; Current Therapy of Pain, and the Journal of Pain and Symptom Management, to name a few.

To educate both patients and doctors about new remedies, specialists are distributing pamphlets, publishing pocket-size emergency guidebooks and providing toll-free telephone services. Self-help groups, such as the National Chronic Pain Outreach Assn., have been formed to guide pain patients and their families seeking appropriate care. And, in more than a dozen states, pain-control lobbying groups have been set up to encourage lawmakers and medical review boards to bring drug regulations into line with current research on pain remedies.

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Perhaps the most concerted effort thus far has come from the World Health Organization. Essentially declaring war on pain, the Geneva-based agency has been trying to focus attention on what some experts now believe to be one of the world’s most serious health problems: cancer pain.

“Cancer itself is a problem of major proportions, but the pain of cancer is also a problem of enormous magnitude, which must be addressed,” said Dr. Kathleen Foley, a neuro-oncologist at Memorial Sloan-Kettering Hospital in New York and head of a WHO panel of pain experts.

Terminal patients are by no means the only ones who suffer. According to epidemiological studies, one in three Americans suffers from chronic pain, or pain that lasts six months or longer. Headaches, backaches and joint ailments are most common. But there are also brutalizing, debilitating sensations caused by nerve disorders, diabetes, sickle cell anemia, strokes.

Why a profession supposedly dedicated to healing has so long ignored pain is a complicated story.

“For centuries, pain has been seen as an inevitable, at times even desirable, accompaniment of medicine. Some view the suffering of women as ordained by God, the agony of post-surgical patients as a sign of recovery,” said a recent article in the medical journal HealthWeek.

“Doctors are subject to the same pressures that face the rest of society, and society has always had ambivalent feelings about pain--hating it on the one hand, thinking it is somehow good for us on the other,” said Dr. Myron Yaster, an assistant professor of anesthesiology at the Johns Hopkins Medical Institutions in Baltimore.

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Nancy Reagan’s “Just Say No” anti-drug campaign and the Bush Administration’s “get-tough” attitude on the illicit drug trade may or may not have had an effect on the use of street drugs. But “it has undoubtedly affected medical care in hospitals, for it has made doctors even more fearful than they already were of addicting their patients,” said June Dahl, a University of Wisconsin pharmacology professor and head of the nation’s oldest pain-control lobbying group--the Wisconsin Cancer Pain Initiative.

More than half a dozen surveys over the last 15 years have shown that the majority of medical personnel--doctors, nurses, medical students--are reluctant to give painkillers, or to give them in adequate doses, for fear that patients will become hooked.

These fears, though heightened by recent anti-drug campaigns, are based largely on widely publicized studies in the 1940s and 1950s suggesting that many people who were addicted to morphine and other opiates became dependent while undergoing medical treatment.

Pain researchers now know those studies included many patients who were addicted when treatment began. The latest, more scientific studies show that “opiates are not addictive” when given for “real pain,” said Canadian psychologist Ronald Melzack in a recent article on pain in Scientific American.

The most widely cited of the recent studies, published in the New England Journal of Medicine in 1980, found that only four of 11,882 hospital patients who had no history of addiction became hooked on narcotics during treatment--about three-hundredths of 1%.

But many doctors continue to avoid powerful natural painkillers, citing side-effects such as nausea, confusion and constipation. Dr. Jamie Von Roenn of Northwestern Memorial Hospital in Chicago recently found that 85% of cancer specialists surveyed acknowledged under-medicating their patients. The vast majority rarely even asked patients about pain.

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“It is instructive to contrast the very low incidence of important side effects with the very high incidence of inadequate pain relief,” Dr. Marcia Angell wrote in an editorial several years ago in the New England Journal of Medicine. “I can’t think of any other area in medicine in which such an extravagant concern for side effects so drastically limits treatment.”

One reason so many doctors shy so far away from treatment is that pain is such a complicated, or, as one physician put it, “messy,” set of psychological and physiological responses. Many pain clinics include psychologists and physical therapists as well as doctors and pharmacologists on their staffs.

That does not mean pain “is in your head, simply that the pain mechanism in the body is far more complex than we ever realized,” said John Reeves, a psychologist specializing in pain management at Cedars-Sinai Medical Center.

Only recently have scientists begun to understand the nature and causes of pain.

Much of current thinking is based on a theory developed in the 1960s by two researchers, Melzack and British anatomist Patrick D. Wall. According to their so-called gate-control theory, pain is not a simple sensation but the result of a complex set of impulses and chemical reactions in the nervous system. The researchers theorized that these impulses are transmitted from an injured area to the brain through a series of circuits, or gates, which exaggerate or tone down the message, depending on what other signals are coming from the nerve or the brain.

Although aspects of the theory have been disputed by recent research findings, the overall notion that pain is complex persists and it has revolutionized pain treatment.

Well before Wall and Melzack, a 17th Century theory by Descartes dominated the thinking about pain. It held that the body contained a simple fire-alarm system that reacted to pain impulses. The only way to treat pain was to remove the source or cut the alarm wires.

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“The common notion was that pain was directly linked to injury. In fact, it turns out that you can be injured and not feel pain or feel pain without injury,” Wall said in 1988.

With that realization, it became clear just how much there was to learn about pain.

One of the oldest and most baffling questions still unanswered is why placeboes--fake medications--work. Placeboes diminish pain at least temporarily in 35% of all pain cases and in as many as 52% of headache cases.

But that does not mean pain is imaginary. Studies at pain clinics have found that as few as 5% of all pain sufferers are hysterical--meaning they have unconsciously made up physical symptoms. What placeboes do illustrate is the “powerful contribution of suggestion” in the perception of pain, Melzack and Patrick Wall wrote in a 1989 book.

Researchers still are mystified over why some people appear to be so sensitive to pain and others so tolerant. Certain cultural differences also seemingly exist in the perception and expression of pain. Surveys have found, for example, that Americans of Mediterranean origin tend to complain of pain more readily and are more overwhelmed by it than Americans of Northern European descent.

Pain can also persist long after the disease or injury that caused it has disappeared. “Phantom” pain most often has been observed in amputees, but it can occur in other instances. In a recent article, Melzack and Joel Katz of McGill University describe ulcer pain that persists after an ulcer has been removed, labor pain and menstrual cramps that continue after a total hysterectomy and burning cystitis that remains after complete removal of the bladder.

These are not “memories” of pain, researchers believe, but actual patterns of nerve impulses that somehow have been encoded in the brain and are periodically or continuously reactivated.

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Equally mystifying is why some people don’t feel pain when it seems they should. Popular lore and medical literature are replete with stories of athletes who perform with broken bones, soldiers who fight with shattered limbs and primitive people who walk on piles of hot coals or lie on beds of nails.

In all cases, something other than drugs or bravery seems to keep them going. Studies conducted in Europe during World War II, in Israel during the 1978 Yom Kippur War and in a large urban hospital in the United States in 1982 all found cases of patients with amputated limbs, life-threatening cuts and broken bones who felt no pain for minutes or even hours after being injured.

Researchers are trying to discover how to harness the mechanisms behind this natural pain-control system. But although some scientists think research eventually will produce a magic pain pill with no side effects, others are less sanguine about the prospects of ever fully understanding pain.

Scientists have long known, for example, of rare cases of people born with complete insensitivity to pain but have yet to understand the reasons why. Although pain insensitivity might seem a blessing, medical literature is filled with problems such individuals face: They bite off the tips of their tongues while chewing food, they scar their mouths by drinking scalding beverages, they burn off their fingertips by touching hot surfaces, they damage their joints by not shifting their weight while standing or turning over in their sleep. Without pain as a warning of danger or disease, a person has little chance of living beyond childhood.

Researchers think most humans are capable of turning pain on and off through a complex set of largely unconscious mechanisms. Studies have shown that pain seems to subside when relief is at hand but seems unbearable when no relief is in sight. Stress, anxiety and the anticipation of discomfort make the sensations of pain harder to bear.

For reasons that also are not clear, antidepressant drugs seem to raise the pain threshold in some patients, although finding the right drug and dosage can be tricky.

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It took years for UCLA chemist Donald J. Cram to find a way to control his “shingles,” or herpes zoster virus. The burning sensation on his back and chest, caused by nerve damage, was so unbearable that he had given up wearing shirts to work by 1987. Although his colleagues grew accustomed to his eccentric dressing habits, Cram realized he had to do something about his problem when he won a Nobel Prize that year. He could not go to the many press conferences and other appearances that awaited him without a shirt--or a coat and tie.

On the advice of doctors at what was then UCLA’s pain clinic, Cram began taking massive doses of antidepressants. The drugs reduced the pain to a tolerable level, but also wiped out his ability to feel emotion. He felt no joy at winning the world’s most coveted scientific prize.

In the years since, Cram’s intake of medication has been regulated so that he experiences emotions and only a moderate amount of pain. The clinic that originally treated him, however, was closed last year by UCLA administrators on grounds that it was not well managed.

“For whatever reasons they may say, pain is simply not a subject that is given much consideration in most medical schools,” said Liebeskind, who teaches the only course on pain at UCLA outside the school of dentistry--a one-term, elective undergraduate course. Although a few premed and nursing students make their way to his classroom, “the vast majority get no formal classroom training in pain management,” said Liebeskind, president of the American Pain Society.

Nor do doctors and other health-care professionals get much from medical texts. Bonica of the University of Washington surveyed 17 standard textbooks on surgery, medicine and cancer, and found that only 54 of the 22,000 pages had any information on pain. Half of the books didn’t discuss the subject.

The results of this seeming indifference can be devastating for patients and their families. Eight years ago, a Northern California man in his 20s hanged himself in the family garage after he was unable to find a doctor who would prescribe adequate pain medication for a bad back.

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To this day, the man’s wife blames the suicide on doctors for their ignorance and on the government for imposing so many restrictions that even knowledgeable doctors are fearful of prescribing adequate doses of medications.

“There have been so many lawsuits against doctors for over-medicating patients in pain,” Liebeskind said. “Perhaps the only thing that will really bring about change is a lawsuit against a doctor for doing too little.”

What is Pain?

Nearly everyone experiences it, but almost no one can find words to describe it. It is what makes some individuals rise to great heights of endurance and courage, and leaves others crippled with fear and anxiety. It is a warning signal that can save a life; left unattended, it can just as easily destroy one.

The PATHWAYS of PAIN

Pain is “felt” not at the site of an injury but in mysterious regions of the brain. Unlike chronic pain, for which there sometimes is no known cause, acute pain is a message to the brain that the body has become damaged or diseased. The message usually is in transit for no more than a second or two, although the sensation of pain may last for long periods.

A) Pain receptors lie in the skin and other tissues and act as terminals for pain messages that will eventually be directed to the brain.

B) When the terminals are stimulated by a burn, blow or other trauma, chemicals are released, sending the message of pain along two kinds of small pain nerves or fibers. One transmits the “first” or “fast” pain; the other dull, continuous pain.

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C) Once in the spinal cord, the pain message is regulated and modulated by the dorsal horn, essentially a relay station for a variety of sensory stimuli. Sensations other than pain--touch or pressure, for example--coming from the injury site may suppress the transmission of signals in the small pain fibers, which helps explain why pain can sometimes be reduced by rubbing an injury.

D) The incoming pain signal in the spinal cord is also modulated by descending signals from the brain. At times of anxiety, pain signals may be amplified. At times of diversion--when playing competitive sports, for instance--the pain signal may not be felt at all.

E) From the relay stations in the dorsal horn, chemicals called neurotransmitters are released, causing nerves in the spinal cord to carry the pain message along two ascending nerve paths to the brain.

F) The classical ascending pathway is the spinothalamic tract, on the side of the spinal cord opposite the injury site. This pathway leads to the thalamus and then to the cerebral cortex, where pain is somehow registered or “felt” within the brain.

G) A second, diffuse pathway known as the spinoreticular tract relays pain signals to islands of grey matter within the brain, and from there to areas of the brain connected with motivations and emotions. It is possible that narcotic analgesics like morphine exert some of their action on this tract. While they do not necessarily eliminate the ability to “feel” pain, they do reduce the “suffering” it causes.

H) When stimulated, parts of the brainstem appear to inhibit or muffle incoming pain signals by the production of endorphins, which are naturally ocurring morphine-like substances. Besides stress and excitement, vigorous exercise may also stimulate the production of endorphines.

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