Pain in women and how it affects nociceptors – a paradigm shift in the awareness of sexisting and masculine genders
Li stresses the need for clinicians to receive more education in pain management, and the potential effects of sex and gender on pain. She says to be more creative and more aware of the human pain experiences there and then try to make it better.
The current situation is not the same. According to Barreveld, she is seeing more papers and presentations about the issue of pain in women. And the number of studies that include both male and female animals is increasing, albeit slowly, Mogil says.
Many women wait years to get help when they do seek it. “We end up seeing these awfully long diagnostic delays,” Chalmers says. Women in Australia often have symptoms of endometriosis for a number of years before they are diagnosed. There are a number of conditions that have delayed diagnoses for women, including heart attack for which women wait longer for a diagnosis and intervention than men. They’re also less likely to be treated appropriately for pain after surgery.
This is especially the case in chronic pelvic pain — an umbrella term for a host of conditions including endometriosis, adenomyosis and prostatitis — which affects an estimated 4–16% of women and 2–10% of men. There is a pain clinic in Boston that stated that they will not see patients with pain related to the Pelvic area, unless it is related to menstruation.
The experience of pain can be influenced by fundamental hormonal differences between genders. The effect of testosterone on pain is straightforward, it is associated with higher thresholds for pain. The effects of oestrogen fluctuations in people with ovaries are more complicated, and it is tied to changes in the intensity and prevalence of pain.
Although pain might be felt locally at the site of the threat or injury, it is processed in the brain. And there has long been interest in the neurological mechanisms of pain, and how those mechanisms differ between sexes and genders.
In one laboratory study11, Porreca and his colleagues looked at how the activity of nociceptors — the nerves that sense pain — were affected by exposure to prolactin. The researchers found that in mice, macaques and humans, prolactin exposure lowered the threshold for activation of those nociceptors, but only in females. They also stumbled on an unexpected second finding: a brain protein called orexin, which has a role in regulating sleep and wakefulness, also sensitized pain receptors, but only in males.
The anterior cingulate cortex, the insula, the amygdala and the wide somatosensory cortices all appear to be part of the brain that is experiencing pain. The subgingual anteriorcingulate cortex, a region of the brain that is involved in pain processing, is one of the topics that Natalie Osborne is interested in.
Gender-affirming hormone treatment for transgender people sheds further light on the role that sex hormones have in pain. The study showed that transitioning from male to female helped with the development of chronic pain during hormone therapy, while decreasing the impact on existing chronic pain conditions.
However, experimental data of pain induced in laboratory settings paints a more complex picture of the effect of oestrogen on the experience of pain. A study found that healthy women who had higher oestrogen levels were more sensitive to thermal pain than those who had low oestrogen levels.
Experiencing migraines is three times more likely to affect women than men, and they occur within two days of menstruation. People with ovaries who have peaked during reproductive years are more prone to have headaches after menopause. The use of oral contraception can increase the severity of migraines, as evidenced by the link.
Pain: Recognizing the Power of Non-Pharmaceutical Interventions – Nature Contributions to the Pacira Cancer Research Outlook
Puberty is a time of big changes in hormones. The hypothalamus in the brain starts producing gonadotropin-releasing hormone, which triggers the testes to produce testosterone and the ovaries to produce oestrogen, both sex hormones.
People spend much of their lives trying to soothe physical pain. The market for over-the-counter pain killers is expected to grow to more than $42 billion by 2032. At the same time, the massive overconsumption of pain-management opioid drugs, which can be addictive, continues to shatter lives.
Several diseases that engender long-term pain are also disproportionately experienced by women — among them are endometriosis and fibromyalgia. But research linking chronic pain to the composition of the gut microbiome is raising hopes that manipulating these microbial communities could provide relief for some conditions.
We are pleased to acknowledge the financial support of Pacira Biosciences Inc. in producing this Outlook. Nature is responsible for all editorial content.
Where and how much does pain feel? A detailed analysis of pain-o-meters, blood tests, and brain scans for precision and objectivity
A more nuanced understanding of what pain feels like is needed to improve the treatment of it. Pain-o-meter devices are emerging that could finally bring precision and objectivity to every carer’s first question: “where and how much does it hurt?”. Researchers are also investigating whether biomarkers in brain scans and blood tests could predict which treatments will work in individuals, curtailing the long search for relief that many people with chronic pain experience.