Ethnic Disparities in Pain: Is Unconscious Bias the Missing Link?

Ethnic disparities in pain

In this op-ed, Elisa Clemente, a graduate student and pain researcher at University College London, UK, discusses the problem of ethnic disparities in pain assessment, management and treatment. Image credit: franzidraws/123RF Stock Photo.

Published 12/4/20

The current COVID-19 pandemic has highlighted problematic healthcare differences across ethnicities. In the UK, data published by the Office for National Statistics (ONS) suggests that individuals belonging to the BAME (Black, Asian and Minority Ethnic) community have been disproportionately affected by the virus. For instance, Black people have been found to be more than four times more likely to die from a COVID-19-related death than age-matched whites.

Despite possible caveats in this study (some ethnic groups may be over-represented in public-facing occupations and thus more likely to become infected, for example), it nevertheless brings to light important issues. Socio-demographic and self-reported health differences cannot fully account for these figures, suggesting that other factors are also playing a role.

But do we experience similar issues in the pain field? Are there disparities across ethnicities when it comes to pain assessment, management and treatment? If so, what causes those disparities and how can we eliminate them?

At the time of this writing, a quick PubMed search of the terms “pain” and “race,” or “pain” and “ethnicity,” yielded a total of 4,161 results. Unfortunately, as summarized in a 2012 review article by researchers at Harvard Medical School, several of these studies come to the same conclusion: there are considerable ethnic disparities in the treatment, progression and outcomes of pain conditions.

In particular, as shown in another review article published in 2009, the pain experienced by Black patients is often underestimated – by laypeople and medical professionals alike – and undertreated, compared to white patients. This review, which examined peer-reviewed research articles published between 1990 and early 2009 that focused on racial and ethnic disparities in pain in the United States, concluded that a number of studies show that Black patients are less likely to receive pain medications, or receive them in lower quantities if they do. This is despite the fact that Black patients often report higher pain levels than white patients do. However, interestingly, most studies did not find these differences to be linked to explicit racist attitudes. What, then, could explain these findings?

A study from 2016 came up with an interesting, albeit rather alarming, explanation: the false belief, shared by a percentage of both white laypeople and white medical students, that Black and white bodies are biologically different – specifically, that Black bodies are stronger. In this study, researchers at the University of Virginia recruited 92 white laypeople and 222 white medical students and residents. Both lay and medically-trained participants were asked to rate the extent to which 15 statements on biological differences between Blacks and whites (for instance, “Blacks’ nerve endings are less sensitive than whites’” or “Whites are less susceptible to heart disease than blacks”) were true.

Lay participants were also asked to report the amount of pain they would feel across different scenarios (slamming their hand in a car door, for example) and to rate the pain of a gender-matched white or Black person in those same scenarios. Medically-trained participants were asked to read two mock medical cases about a Black and a white patient, and to make pain ratings and treatment recommendations.

The study’s results were perplexing. For instance, a large percentage of lay (58%) and medically trained (between 22% and 42%) white participants endorsed the belief that “Blacks’ skin is thicker than whites.’” Importantly, the extent to which study participants believed in these false biological differences predicted racial bias in pain perception. That is, participants who endorsed more false beliefs were more likely to underestimate Blacks’ pain, compared to whites’ pain. Worryingly, this was reflected in the accuracy of pain treatment recommendations: medically trained participants who endorsed more of the false beliefs (and therefore showed a greater racial bias in their perception of others’ pain) were less accurate in treatment recommendations for Black patients, compared to white patients.

This study had a few limitations. For instance, it relied on surveys to assess beliefs and bias, rather than more objective measures; it only used mock medical cases; and it did not look into doctors at later stages of their careers. Nevertheless, the study raises important questions about whether unconscious bias, as reflected by these false beliefs, could help explain ethnic disparities in the treatment, progression and outcomes of pain conditions.

These findings replicated results from previous reports. For example, a 2012 study found correlations between pediatricians’ unconscious racial biases and how they treated pain, in a simulated scenario. In this case, researchers at the University of Washington carried out an online survey of 86 academic pediatricians and measured implicit attitudes and stereotypes about race using multiple Implicit Association Tests (IATs). The IAT measures the strength of associations between concepts (for example, Black people, gay people) and evaluations (good, bad) or stereotypes (athletic, clumsy). The researchers found that unconscious attitudes and stereotypes were associated with treatment recommendations, such that the stronger the white-favoring bias, as assessed by the IATs, the lower the likelihood of prescribing appropriate pain medication for Black patients.

Interestingly, the discrimination, along with patients’ lack of trust in their healthcare providers, that could conceivably result from such biases can actually have direct consequences on pain sensitivity.  Specifically, a recent study from earlier this year found that African Americans reported more pain than white Americans in response to the same experimental heat stimulus and that these differences arose from sociocultural factors such as discrimination.

The study authors also found that participants’ history of responding to discrimination mediated the relationship between their ethnicity and pain ratings. That is, the frequency of responding to discrimination was higher in African American participants than in white Americans and it predicted higher pain ratings. This suggests that a history of responding to discrimination may predispose people to react more strongly to physically painful stimuli. The incidence of discrimination and of distrust in the experimenter (a white male wearing a lab coat) were also significantly different among the two groups. Additional experiments using brain imaging would show that certain regions of the brain may become sensitized to painful stimuli in people with a history of negative social treatment.

Together, these findings suggest that life experience, rather than inherent biological differences, underlies the observed differences in pain sensitivity between ethnic groups. This further highlights the need to tackle unconscious bias in pain assessment, particularly since this bias leads to an underestimation and undertreatment of the pain experienced by Black patients.

Unfortunately, one of the greatest problems of unconscious bias (also known as implicit bias) is precisely that it is so – unconscious. It’s hard to challenge misconceptions you don’t even know you have. What, then, is there to do?

The answer is far from simple. Of course, unconscious bias is not an issue exclusive to the pain field. In fact, unconscious bias relating to gender and ethnicity is increasingly being recognized as a problem in the wider society, for example, when it comes to recruitment and promotion in the workplace. For instance, a 2010 study by a researcher at Linnaeus University found that unconscious bias was correlated with discriminatory behavior among recruiters in a simulated hiring situation. In this case, negative unconscious bias towards Arab-Muslim male names correlated with a lower probability to invite Arab-Muslim job applicants for an interview, compared to men with Swedish names.

Unconscious bias training in the workplace has been proposed as a possible way forward. However, many people are skeptical that it will help, arguing that bias awareness does not automatically lead to changes in behavior. Others worry that viewing it as a “silver bullet” may be problematic, because this training is unlikely to be successful in completely removing unconscious bias if used on its own.

Nevertheless, a report by the UK Equality and Human Rights Commission indicated that unconscious bias training can be effective for raising awareness of and reducing unconscious bias in the workplace, although it was unlikely to completely eliminate it. This training should, however, be part of a comprehensive program for achieving long-lasting, organization-wide change.

It would be extremely interesting to learn whether unconscious bias training for healthcare providers, together with other measures, could similarly help change racial and ethnic bias regarding pain and reduce the disparities in pain assessment, management and treatment. The evidence shows those disparities are real. Now it’s time to do something about them.

Elisa Clemente is a PhD student at University College London, UK.