Studies show pain disparity among minorities

Research on minorities examined

An African-American patient is more likely to endure disease-related pain than his or her white counterpart. Experts in end-of-life care have noted this fact for years, and now a recent University of Michigan research study has drawn a similar conclusion. The study report, written by a panel of top pain experts and based on a survey of more than 180 pain-related studies from a broad range of specialties, documents a phenomenon that pain specialists have long suspected but still don’t fully understand.

The authors and researchers with the American Pain Society (APS) pulled together research on racial and ethnic disparities in the perception, diagnosis, and treatment of pain in treatment locations ranging from emergency departments to cancer clinics. They studied conditions ranging from chronic pain to acute pain induced in laboratory experiments.

Their conclusions were published in the September issue of the journal Pain Medicine.

"Across the board, and consistently, there are racial and ethnic differences in pain," says lead author Carmen R. Green, MD, an anesthesiologist and pain management specialist at the University of Michigan Health System in Ann Arbor and chairwoman of the APS special interest group on racial and ethnic disparities in pain. "There’s much we still don’t understand about why these health disparities based upon race and ethnicity exist, so more research is needed. We hope our work will increase awareness of this issue among patients and providers alike."

The new paper echoes the recently published findings from the Institute of Medicine’s (IOM) panel on health disparities, which collected evidence of racial and ethnic differences in many areas of medical and surgical care. The IOM panel’s report included some perspective on differences in emergency and cancer pain treatment. But the new paper goes further by including data from more fields, including chronic pain and disability, and considering pain medication access issues. It also offers recommendations for future research.

Also, the journal Cancer published a study earlier this year noting the disparity in pain management. According to the journal, cancer pain among minorities often goes undertreated compared to cancer pain among whites. The results of the study were published in the April 15 issue of the journal. Researchers talked with 31 cancer outpatients, 17 Hispanic and 14 African-American. Many of the participants told researchers that they didn’t understand the best way to use pain medications or that they hadn’t been warned in advance about possible side effects and how to control them.

Researchers also found that 75% of the patients said they experienced severe pain. While they got information from many sources, patients told the researchers that doctors are the most frequent and most trusted sources for information regarding cancer and cancer-related pain. Researchers of the study published in Pain Medicine found more examples of studies that support the theory that minorities are less likely to receive adequate pain management than whites.

Knox Todd, MD, MPH, of the Rollins School of Public Health at Emory University in Atlanta, who co-authored the latest study, looked at emergency medicine studies that showed Hispanics with broken bones in their arms or legs were twice as likely as non-Hispanic whites to go without pain medication in their emergency department visits, even after differences in language, gender, and insurance status were taken into account.

Another study co-author, Karen O. Anderson, PhD, of the M.D. Anderson Cancer Center in Houston, cited studies of cancer pain. One study showed that Hispanics and African-Americans with cancer were less likely to be assessed for pain and did not receive the level of pain medications recommended by the World Health Organization. Another study showed that African-American cancer patients in nursing homes had a 64% greater chance of receiving no pain treatment than did non-Hispanic whites.

The report also draws on Green’s work in the area of chronic pain, including her recently published findings that, regardless of their age, African-Americans with chronic non-cancer pain from any source suffered more psychological and physical effects than non-Hispanic whites with chronic non-cancer pain.

Pain tolerance varies by ethnicity

In addition to these clinical pain studies, the authors describe the racial and ethnic differences in pain sensitivity and pain response that have been found in numerous experiments. For instance, scientists using pressure, heat, or cold to induce pain have found that African-Americans and Hispanics tend to have lower thresholds of pain tolerance. Other studies have found that pain-study participants from Nepal and India had higher pain tolerances than Western counterparts.

Taken together, these findings suggest that something in the brain’s pain-processing and pain-killing systems may vary by race and ethnicity. But more studies are needed to know for sure, writes co-author Roger Fillingim, PhD, of the University of Florida College of Dentistry in Gainesville.

Researchers also examined how communication between patients and health care providers, and the social context of their interaction, can influence pain diagnosis and treatment. They cite a number of studies showing that African-Americans and members of other racial and ethnic minorities are consistently undertreated for pain across a range of conditions, from cancer and chest pain to post-surgical and chronic lower-back pain.

Access to pain medications can also vary by race and ethnicity, the authors find. They note findings that pharmacies in neighborhoods with large minority populations tend not to carry narcotic pain medicines such as morphine out of fear of being robbed or burglarized. This contributes to reduced minority access to pain management drugs. In addition, people living in high-crime neighborhoods are reluctant to keep these drugs at home for the same reasons pharmacies do not stock them..

Past studies have cited a sense of mistrust toward the health care system among African-Americans. Studies suggest that communication between African-Americans and their physicians may be hampered by that mistrust and that physicians must make a greater effort to explain courses of treatment and listen to patient concerns in order to gain patients’ trust.

Also, the way health care providers measure pain is an issue. Rather than arbitrarily choosing an unacceptable level of pain for the entire population, health care providers need to gauge pain on individual preferences. For example, if 10 people report varying degrees of pain, half of them more than a 5 on a 1-to-10 scale, it would be reported that half the patients were made to endure moderate to severe pain. Instead, providers should consider an individual’s tolerance for pain, which is often based on cultural factors. For example, Hispanics, with their deep roots in Catholicism, may be willing to endure higher degrees of pain. Also, fear of addiction is prevalent among minorities.

"Physician prescribing patterns, as well as patients’ own attitudes and beliefs regarding pain, and socioeconomic factors, may all contribute to racial and ethnic differences in pain management," writes study co-author Raymond Tait, PhD, of the St. Louis University School of Medicine. "But all of these issues related to health care delivery are yet to be adequately explored."

In fact, says Green, a review of the literature on race, ethnicity, and pain only showed the authors how much more there is to find out on this topic. For instance, much more research is needed on how cultural beliefs, as well as patient-level decision-making and preferences, influence the pain-related behavior of patients from racial and ethnic minorities. Further studies should be done, the authors say, to correlate experimental findings on pain perception and tolerance with clinical pain, especially where there are differences among racial and ethnic groups.

Even the tools that doctors and nurses use to ask patients how severe their pain is need to be examined for cultural and linguistic sensitivity, the study’s authors suggest. Better data on disparities in various health care settings, and in different insurance and legal contexts, should be gathered. And more studies are needed to understand how stereotypes and other sources of bias can color the interaction between health care providers and patients, and what strategies might counteract these effects.

"Clearly, local, state, federal, and private-sector initiatives, in combination with advocacy and scientific organizations, are necessary to understand racial and ethnic disparities in pain if we are to improve the quality of pain care for all," says Green. "In the meantime, it’s important for patients from all backgrounds to speak up about their pain to their health providers and insist on getting the effective treatments that now exist, along with referrals to pain specialists. Don’t assume that pain has to be a part of your life."