Scientists Study Children Who Feel No Pain

This is SCIENCE IN THE NEWS, in VOA Special English. I'm Faith Lapidus.  And I'm Bob Doughty. Today we tell about some recent studies of pain, and new possibilities for controlling it.

Have you ever wished you could not feel pain? There are people in the world with this ability. They do not know when they are hurting. If you have ever broken a leg or given birth, this might sound good to you. But a person unable to feel physical pain can be in danger and not know it.

Last year, Nature magazine published a report about six children who have never suffered pain. C. Geoffrey Woods of the Cambridge Institute for Medical Research in England and his team wrote the report.

The six children come from three families from northern Pakistan. The research team found the children after hearing about a boy who apparently felt no pain. The boy stood on burning coals and stabbed his arms with knives to earn money. He died in a fall before the researchers could meet him.

But the team was able to find members of the boy's extended family. They also seemed unable to feel pain.

These children were six to fourteen years of age. They sometimes burned themselves with hot liquids or steam. They sat on hot heating devices. They cut their lips with their teeth, but felt no pain. Two of the children bit off one-third of their tongue.  Yet they could feel pressure and tell differences between hot and cold.

Doctor Woods and his research team studied DNA -- deoxyribonucleic acid -- from the children. They also examined DNA from the children's parents. The team found that all had a gene with a mistake, or fault. Except for the genetic fault, the children had normal intelligence and health. The researchers found that each child received a faulty version of the gene from a parent.

The gene is called SCN9A. It gives orders to a protein that serves as a passageway for the chemical sodium. All nerve cells have such passages. This is how pain signals from a wound or injury are communicated to the spinal cord and brain.

Two years ago, investigators at Yale University in the United States discovered something important about SCN9A. They linked it to a rare condition in which patients suffer painful burning in their feet or hands. The problems of these patients were nearly opposite to those of the children who felt no pain. In patients with the burning hands and feet, SCN9A was too active.

The findings of the British and American groups may mean better medical help for pain. Doctor Woods' team says this could happen if medicine can be developed to control the faulty gene. That would be welcome news to people whose pain resists current medicines.

Another report says many Americans believe they are suffering more pain now than in earlier years. The National Center for Health Statistics released the report last November. The center is an agency of the Centers for Disease Control and Prevention.

Twenty five percent of American adults said they had a full day of pain in the month before they were questioned. Ten percent were more deeply affected. Their pain continued for a year or more.

Amy Bernstein was lead research writer for the study. Ms. Bernstein said pain is rarely considered as a separate condition. Yet she said costs linked to pain overload the health care system.

The study found that lower back pain was a big problem. More than twenty five percent of adults who were asked said they had lower back pain in the past three months.

Painful knees caused the most trouble of the body's joints. But some victims of knee pain are doing something about it. They are having operations to replace the painful joint. Their replacement knees are man-made, or artificial.

Starting in nineteen ninety-two, rates of hospital stays for knee replacement rose almost ninety percent among older Americans. The patients were sixty-five years of age or older.

Americans also reported head pain. Fifteen percent of adults said they suffered a migraine or other severe headache in the past three months. This pain affected young people three times as much as older adults.

Reports of severe joint pain increased with age. Women said they had painful joints more often than men.

The study showed that painful conditions caused increased use of narcotic drugs. Narcotics can be strong painkillers. The study compared two periods. One period lasted six years and ended in nineteen ninety-four. The other began in nineteen ninety-nine and ended four years ago. Between those periods, the percentage of adults who said they used a narcotic for pain in the past month rose from three to four percent.

Doctors usually order opiates for patients with severe pain. Opiates include morphine, codeine and methadone. Most of these drugs come from the poppy flower. Doctors have used one opiate, opium, to treat pain for more than two thousand years. A newer drug, oxycodone, is called an opioid. An opioid is similar to an opiate. Doctors use it to control moderate to severe pain over a long period.

For example, a woman from Rockville, Maryland, has a painful back. Her doctor says he cannot operate on it without putting her in danger of losing the use of her legs. The woman was in severe pain much of the time until the doctor ordered a form of oxycodone. She still has pain at some times of day. But she is able to work at home and take part in at least some of the activities she loves.

Many doctors order, or prescribe, narcotic drugs for patients with continuing severe pain like that of the Maryland woman. Narcotic drugs may help to decrease pain, but can make many people sleepy. They also can be addictive. The user may need increasing amounts to get the same effect.

Some doctors have prescribed more narcotic drugs than are medically necessary. Doctors face possible arrest and jail sentences if they knowingly order narcotics for other than medical reasons.

Non-medical use of oxycodone and similar drugs has killed many Americans. Some people break them up and mix them with other drugs.

Recently, the Centers for Disease Control and Prevention reported an increase in the number of accidental deaths from prescription drugs. C.D.C. officials say the number increased more than sixty percent between nineteen ninety-nine and two thousand four. That made accidental drug-poisoning the second largest cause of accidental death in the United States. Only traffic accidents rated higher.

The C.D.C. got its information from official death reports. The reports do not always clearly state which drugs are involved. But researchers say they believe painkillers ordered by doctors caused the increase.

Clearly, strong painkillers can be dangerous, but many patients need them. To meet this need, some doctors and hospitals today provide special services for such patients. For example, doctors who teach at the University of Cincinnati School of Medicine in Ohio offer advice and treatment for several kinds of pain.

As you hear this program, research into pain continues around the world. Recently, an English study suggested that women feel pain more than men. Psychologist Ed Keogh says the study found that women also feel pain in more body areas than men. It also found that women suffer pain more often and for longer periods than men.

In the study, several people at the University of Bath held one arm in warm water. Then they put the arm in icy cold water. Both men and women were told to think about the physical nature of the pain. They were not to think about their emotional reactions to it. Using this psychological trick, men said they felt less pain than women.

Mr. Keogh says many explanations of these differences depend on genetic and hormonal influences. But he says psychological and social reasons also are important.

One medical worker who has cared for hundreds of people says it is never fair to say someone is making too much of their pain. She adds that no one can ever know what other people are feeling.

SCIENCE IN THE NEWS was written by Jerilyn Watson. Our producer was Brianna Blake. This is Bob Doughty. And this is Faith Lapidus. Join us again next week for more news about science in Special English on the Voice of America.