It is now well established that men and women show general differences in how they report and experience pain – women tend to report more pain, with greater severity and frequency than men. Examples are numerous, and range from laboratory-based pain induction studies on healthy adults through to epidemiological and clinical investigations of chronic pain. Recent studies show a greater female vulnerability to post-surgical pain (Tighe et al., 2014), and a higher incidence of persistent pain in women compared to men (Kennedy et al., 2014).
The question naturally turns to why these gender differences occur. Explanations are likely to reflect the biopsychosocial nature of pain. However, most have focused on biological (e.g., sex hormones) and psychological mechanisms (e.g., pain-related catastrophizing; gender-role expectations and beliefs), with less attention placed on social factors.
Fortunately, we are currently seeing a social (research) revolution, with greater recognition that pain does not happen in isolation. There is increasing awareness that pain assessment and treatment involves social interactions and negotiations e.g., between healthcare providers and patients, parent and child etc. How pain is communicated to others is also important, and we know this occurs through both verbal and nonverbal channels. Thus, alongside self-reports, we can also measure pain through a range of nonverbal cues, including facial expressions (grimaces), nonverbal vocalisations (cries, groans) and certain body postures and movements (guarding). This is particularly important when we consider situations where it is not possible for patients to verbally communicate to others about their internal, subjective pain state such as pre-verbal children, and patients with dementia. Attempts are now being made to isolate and measure these nonverbal cues in a reliable and objective manner.
These issues are relevant to our understanding of gender differences in pain, and I believe there is much to be gained by taking a social communication approach (Keogh, 2014). Indeed, the well-established gender differences in nonverbal communication that have been found in the general area of emotion expression research, corroborate the idea of using a social communication approach in pain. In emotion expression research, women seem to be more expressive and better at recognising a range of core emotional expressions than men, for example, women are more likely to smile than men. Whilst pain and emotion are not the same, they do seem to operate through similar nonverbal channels. It would, therefore, seem sensible to at least consider whether male-female differences exist in the generation and recognition of pain expressions.
So what does the evidence tell us for pain? Unfortunately, there are relatively few studies that set out to directly explore gender differences in nonverbal pain communication. Of the studies that have been conducted, most focus on facial expressions of pain, where an interesting pattern is starting to emerge. Whilst there are few reports of gender differences in the generation of facial expressions of pain, there may be differences in how such expressions are recognised. However, the nature of this difference is still unclear, since a range of methods and approaches are used to measure such interactions. Furthermore, we do not know whether gender differences exist in other nonverbal channels of pain communication, such as in vocal and body expressions.
Rather than view these unanswered questions as problematic, I view this as an exciting new direction for gender and pain research. What a nonverbal approach brings to the fledgling area of male-female pain communication is a range of tried and tested techniques that allow us to consider the dynamic nature of social exchanges between individuals within the context of pain. For example, we are currently developing new body posture stimuli sets (Walsh et al., blog post here), which will hopefully enable us to look at gender differences in the recognition of pain and core emotions. Such an approach also leads us to consider interpersonal factors in more detail, as well as whether the gender context is important for pain. For example, do male and female healthcare providers pick up on different types of verbal and nonverbal information, and if so, what effect does this have on choices around treatment? We might also find gender pays a role in understudied groups of patients, especially children, where nonverbal behaviours are critical.
In sum, I believe that we are on the cusp of an exciting point in our understanding of gender-related issues in pain. Taking a pain communication approach should help us understand more about why there may be gender differences in pain and pain behaviour. In addition, I hope that those with primary interests in pain communication consider the gender context in more detail, thus adding an extra dimension to their work.
About Ed Keogh
Ed is Deputy Director of the Bath Centre for Pain Research and a Reader in the Department of Psychology, both based at the University of Bath in the United Kingdom. His primary research interests are in understanding why there are sex/gender differences in pain, with a focus on psychological factors. He also has interests in pain communication, and the role of attention in our perception and experience of pain. He is currently co-chair of IASP’s Special Interest Group on Sex, Gender and Pain.
References
Kennedy J, Roll JM, Schraudner T, Murphy S, & McPherson S (2014). Prevalence of persistent pain in the U.S. Adult population: new data from the 2010 national health interview survey. J Pain 15 (10), 979-84 PMID: 25267013
Keogh, E. (2014). Gender differences in the nonverbal communication of pain: A new direction for sex, gender, and pain research? Pain, 155 (10), 1927-1931 DOI: 10.1016/j.pain.2014.06.024
Tighe, P., Riley, J., & Fillingim, R. (2014). Sex Differences in the Incidence of Severe Pain Events Following Surgery: A Review of 333,000 Pain Scores Pain Medicine, 15 (8), 1390-1404 DOI: 10.1111/pme.12498
Walsh, J., Eccleston, C., & Keogh, E. (2014). Pain communication through body posture: The development and validation of a stimulus set Pain, 155 (11), 2282-2290 DOI: 10.1016/j.pain.2014.08.019