After 36 agonizing 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 Samuels's 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, leaving her unusually sensitive to even the slightest irritation.
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."