BRANDYWINE, Md. – After 36 years with sickle cell disease, Tesha Samuels is in complete remission — free, at least for now, of one of the most painful disorders known to medicine.
Yet her body still hurts almost every day. The question that perplexes her doctors at the National Institutes of Health is why, after her blood disorder has been vanquished, she is still in pain.
Perhaps her newly healed red blood cells are not yet bringing enough oxygen to her tissues. Perhaps the emotional toll of a lifetime of constant pain has left her prepared to feel little else. Or perhaps the pain signals that have flooded her brain for more than three decades have permanently rewired some circuits.
There is evidence for all these theories, and more. But the truth is that no one really knows why pain persists in some people.
More than 5,000 years after the Sumerians discovered they could quell aches with gum from poppies, medical science is still uncertain about who will develop chronic pain, how to prevent it and what to do when it occurs. The reasons the same insult to the body can leave one person with short-term discomfort and another with permanent misery have eluded researchers.
"Chronic pain is incredibly complex," said Benjamin Kligler, national director of the Integrative Health Coordinating Center at the Veterans Health Administration. "It is interwoven with all kinds of psychological, emotional and spiritual dimensions, as well as the physical. Honestly, the profession of medicine doesn't have a terribly good understanding, overall, of that kind of complexity."
Now NIH, university researchers, Veterans Affairs and drug companies, among others, are reexamining chronic pain, hoping to develop new approaches to predicting and preventing an ancient malady that afflicts 50 million adults in the United States.
New discoveries could transform the treatment of long-term pain, allowing doctors, psychologists, physical therapists and others to intervene before pain becomes chronic, or provide alternatives to drugs when it does.