Photo illustrations by Matt Mahurin
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Rooting Out Pain
By Elizabeth Enright, September & October 2004
One third of Americans will have chronic discomfort. Finally, new discoveries—and new drugs—offer a hope of relief
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By the time she finally went to see a pain-management specialist two years
ago, Dorothy Koss-Fillinger was taking 3,600 milligrams a day of Neurontin, a
powerful nerve desensitizer, and getting little relief. Three surgeries,
radiation, and four months of chemotherapy to combat recurrent soft-tissue
sarcomas had left the Phoenix, Arizona, resident with debilitating nerve pain
that spread across the back of her thigh and buttocks. She couldn't drive
or even stand for any period of time. "The only way I felt okay was lying
on my back with my knees up," says Koss-Fillinger, 56. Her oncologist
prescribed one painkiller after another—Percocet, Vicodin, then finally
Neurontin. Each worked initially but eventually stopped working. "It was
horrible," she says. "Everything I did and did not do was centered
around my pain."
What finally brought her some relief was a small pump implanted under the
skin of her abdomen that slowly releases a cocktail of medications into her
central nervous system. Like a chef perfecting a prize recipe, her pain doctor
fiddled with the proportions until she got it right—a mixture of the
narcotic analgesic morphine, the muscle relaxant baclofen, and the numbing
agent bupivacaine. She also prescribed a lollipop that releases the painkiller
fentanyl for times when there is intermittent pain that the other drugs
don't relieve. Although she still cannot hike eight miles a day as she used
to, Koss-Fillinger feels she has her life back. "It's as good as
it's going to get," she says.
Only 10 years ago, medications for nerve pain—considered the hardest
kind of pain to treat because it is less responsive to painkillers—were
few in number and typically administered one at a time. But an explosion of new
drugs and new treatment strategies is giving people like Koss-Fillinger a shot
at controlling their pain. Many of these medications were created for other
uses. Neurontin, for example, was developed to treat seizures, and Elavil,
which is routinely prescribed for pain, is an antidepressant. "When I
started in pain management, apart from narcotics and anti-inflammatory drugs
there were only two medications commonly used—Tegretol and Elavil,"
says Russell Portenoy, M.D., chair of the Department of Pain Medicine and
Palliative Care at Beth Israel Medical Center in New York City. "Now I
have more than 50 medications to pick from. I have no way of knowing which a
patient will respond to, so my approach is one of trial and error."
This bounty of new choices offers desperately needed hope to the estimated
one third of Americans who will suffer from chronic pain at some time in their
lives. Pain is the number one reason people seek medical care, costing an
estimated $100 billion a year in treatments, lost wages, and other costs,
according to the National Institutes of Health.
Yet until fairly recently, pain management was considered secondary to
treating disease. Medical schools taught almost nothing in the way of pain
management. Even patients were reticent to talk about their suffering.
"They didn't want to distract the doctor from taking care of their
disease," says Portenoy, coeditor with Eduardo Bruera, M.D., of Cancer
Pain: Assessment and Management (Cambridge University Press, 2003).
"They didn't want to be labeled complainers."
These attitudes are finally changing. "We have gone from thinking of
pain as a symptom to viewing it as a disease which, if untreated, can be very
disruptive to a person's life," says Richard Payne, M.D. (yes,
that's really his name), director of the Duke University Divinity School
Institute on Care at the End of Life. Doctors increasingly acknowledge the huge
impacts of chronic pain on an individual's life and society in general.
More treatment breakthroughs are on the way, such as an injection to interrupt
the electrical impulses that transmit pain. "We're on the cusp of
finding new ways to modulate pain," says Lee S. Simon, M.D, associate
clinical professor of medicine at Harvard Medical School and Beth Israel
Deaconess Medical Center in Boston. "This is a critical time because we
have learned so much and now we need to apply it."
And researchers continue to hunt for pieces of this vast and confounding
puzzle. It is now clear that pain is a subjective experience. Different
diseases also cause different kinds of pain—the pain of osteoarthritis is
different from the pain of cancer, which is different from the pain following
surgery. "There is no single treatment for all kinds of pain," says
Clifford Woolf, M.D., Ph.D., professor of anesthesia research at Massachusetts
General Hospital and Harvard Medical School in Boston. "In the future,
treatment for pain will be mechanism-based as opposed to symptom-based. The
challenge will be to identify which pain mechanisms are at work and find out
which drugs act on those targets."
So if you're among the estimated 50 million Americans currently living
with chronic pain, what does this news mean to you? It means that there is more
hope for relief than ever before. Here are the latest findings and treatments
for each of the major types of pain.
Lower-Back Pain
Why It Hurts
"Your spine is one of the first
parts of the body to show degenerative changes," says Richard Deyo, M.D.,
professor of medicine and health services at the University of Washington in
Seattle. Mechanical problems caused by anatomical changes can lead to
degenerative disks or narrowing of the spinal column, called spinal stenosis,
which can pinch the nerves in the leg and lower back. Chronic lower-back
pain—especially if it's unremitting or accompanied by leg numbness or
weakness—can mean a serious condition such as cancer or vascular disease.
But pain caused by mechanical problems is far more common. "By age 50,
probably half of us have such changes," Deyo says.
What Helps
- Movement: Recent studies have shown that bed rest—once the mainstay of
treatment for an aching back—does not make the pain go away any faster
and can lead to debilitation and depression. Patients whose pain is caused by
nerve impingement could seriously injure themselves by doing the wrong
exercises, but experts now believe that for muscular lower-back pain, the more
exercise you can tolerate, the more relief you will get. And even those with
nerve pain can get some relief with exercises carefully tailored by a doctor.
Mobility increases your ability to handle pain, which, in turn, reduces
it.
- Medicine: Some old-fashioned tricyclic antidepressants such as Elavil,
Norpramin, and Aventyl can be effective in treating lower-back pain. New
long-acting analgesic opioids such as OxyContin, fentanyl, and MSContin are
also effective for pain that has resisted other medications.
- Vertebroplasty: This nonsurgical technique can relieve pain by
strengthening a cracked vertebra. The doctor injects an orthopedic cement into
the bone, which stabilizes as the cement hardens. Vertebroplasty is recommended
for those with fractures due to osteoporosis if simpler treatments such as a
back brace or medications have failed.
- Surgery—for some: While orthopedic procedures such as laminectomy may
work as a last resort to relieve chronic lower-back pain, they are proven
effective only for the small minority of patients with a herniated disk that is
causing sciatica, or those with spinal stenosis and leg pain.
Arthritis
Why It Hurts
More than 100 conditions that cause joint swelling and pain fall under the
umbrella term arthritis. The condition affects an estimated 70 million
Americans, or one in three adults. The most common form is osteoarthritis, a
degenerative disease caused in part by wear and tear. Cushioning cartilage
breaks down, allowing bones to rub against each other, which leads to pain,
stiffness, loss of movement, and inflammation. Other forms of arthritis are
systemic, which means they affect all the organs of the body. In rheumatoid
arthritis, for example, the body's immune system attacks joint linings.
Chemicals interacting at the site of inflamed joints act on pain-sensing nerves
and make them even more sensitive, which turns up the volume on pain.
Jon Levine, M.D., Ph.D., a professor of medicine at the University of
California, San Francisco, who is researching the mechanisms of pain on a
molecular level, has found that chronic inflammation from arthritis actually
causes tissue changes over time. That explains why a drug that eased your
arthritis pain for years may have gradually stopped working.
What Helps
- Movement: Along with its other benefits, regular exercise—whether
weight-bearing, flexibility, or aerobic—is known to reduce joint pain and
stiffness among arthritis sufferers.
- Medicine: Some of the cheapest and most effective drugs for arthritis pain
are sold over the counter. Simple analgesics like acetaminophen relieve pain.
Anti-inflammatory drugs such as aspirin, ibuprofen, and naproxen reduce both
pain and inflammation. The newest generation of non-steroidal anti-inflammatory
drugs (NSAIDs)—such as Celebrex and Bextra—are also top
choices for pain associated with arthritic inflammation. Called COX-2 selective
inhibitors, these drugs work by blocking the work of an enzyme (cyclooxygenase
2) that sparks a cell's production of prostaglandins, the hormones that
cause arthritic pain and inflammation. Compared with ibuprofen and aspirin,
COX-2 inhibitors carry a low risk of causing changes in the stomach lining that
can lead to ulcers. The next generation of NSAIDs, which are being called p38
MAP kinase inhibitors, will go even further in reducing inflammatory pain. They
are not expected on the market for several years, however.
Drugs that block a body chemical called tumor necrosis factor (TNF) are a
major target of research. Excess TNF plays an important role in sparking
inflammation, and a class of drugs called TNF inhibitors addresses the problem
in arthritic conditions such as ankylosing spondylitis and rheumatoid
arthritis. The three currently on the market are Enbrel, Humira, and Remicade.
Unfortunately, the cost can run many thousands of dollars a year.
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