Women experience more chronic pain and they're less tolerant of the pain than men, according to a new review of research.
Women feel more pain and have a harder time coping with pain than men do.
Pain management strategies of the future might be more individualized and gender-based.
"Globally, women have more chronic pain than men, more recurrent pain, they are more likely to have multiple sources of pain, and they are definitely neglected as it relates to treatment," said Jennifer Kelly, an independent psychologist in Atlanta.
Kelly presented a review of research on gender and pain today at a meeting of the American Psychological Association.
Along with findings that a combination of genes, hormones, emotions and even social roles influence the experience of pain, accumulating evidence suggests that doctors might some day personalize the management of pain, based on the genders of their patients. For now, scientists are still struggling to understand the nuances of chronic pain, which is notoriously hard to treat.
"What I learned from all of my research is that you should treat women differently than men," Kelly said. "We have to get women to see this as something they can manage instead of it having some kind of power over them."
For years, studies have suggested that women and men differ in how they experience pain. As Kelly pulled together the literature, she found that those differences to be both real and dramatic.
A variety of chronic and painful conditions, for example, are far more common in women, including migraines, rheumatoid arthritis, irritable bowel syndrome, and fibromyalgia -- which affects at least four times more women than men. Women are less tolerant of pain. Their pain lasts longer. And they are more likely to become disabled by it.
"What's interesting is that there are gender differences across a lot of different measures of pain," said Beverly Thorn, a psychologist at the University of Alabama in Tuscaloosa. "It holds for acute pain, experimental pain, recurrent pain like migraines, and chronic pain like in the lower back."
Hormones play a part, as many symptoms worsen around that time of the month. Other biological differences come into play, too. Certain painkillers work better in males, at least in animal studies. And women experience more side effects from pain medicines.
But a significant portion of the gender imbalance may come from social and psychological factors. Multiple studies have found that women are more likely to get depressed as a result of chronic pain, and they have a higher tendency to catastrophize, Thorn said.
They think, "Oh my God, this is the most terrible pain I've ever had. I can't stop thinking about it and there's nothing I can do," she said. "There is helplessness, magnification and rumination."
In experiments that challenged people to hold their hands in ice-cold water, one of Thorn's students found that people who tolerated the pain longer were less likely to have catastrophic thoughts and less likely to have emotionally vulnerable personalities. Emotional vulnerability is a traditionally feminine trait, Thorn said, and even women who play traditionally masculine sex roles have higher levels of pain tolerance and feel pain less intensely.
What was particularly interesting about the ice-water experiments, Thorn said, was that the men, who tended to be more pain-resistant, actually had higher levels of stress hormones and higher spikes in blood pressure.
At first, the researchers thought this meant that the men were acting more macho -- feeling more stress internally but defying it outwardly. But then other research linked higher blood pressure with lower responsiveness to pain, suggesting that physically, the men's experience really was different.
"I say that to point out," Thorn said, "that this is a really intricate collaboration among biological, social and psychological factors."
Acting macho, she added, is not going to help women cope with pain like men do. Instead, they need to accept the pain and learn how to think about it as something they can live with instead of something they're trying to defeat. Multidisciplinary therapy can make a big difference.
"At the end of their treatments," Thorn said, "my patients say, 'I still have the pain. But the pain doesn't have me.'"