People living in predominantly minority areas face significant barriers to accessing pain medication

Chronic pain is a condition that affects one in five Americans without regard for their race or finances. But a new study finds that minorities and people with low incomes have less access than high-income white people to the medications that will help them endure their pain.

In a wide-reaching study of 95 pharmacies in ZIP codes with predominantly white populations and 93 pharmacies in ZIP codes with predominantly minority populations, researchers at the University of Michigan Health System’s Department of Anesthesiology found a pronounced gap in the availability of prescription opioid analgesic medications.

The study, which appears in the new issue of the Journal of Pain, found that Michigan pharmacies in predominantly minority areas were significantly less likely to have sufficient supplies of prescription opioid analgesic medications – drugs that include oxycodone, morphine and methadone – when compared with predominantly white areas.

In addition, the odds of not having sufficient supplies of opioid analgesics – also known as narcotics – are significantly higher among pharmacies in low-income areas compared with high-income areas, regardless of the racial makeup in the vicinity.

“The key finding is that there are differences in the ability to obtain pain medications in local pharmacies, with the lowest availability in minority and low-income areas,” says lead author Carmen R. Green, M.D., associate professor in the U-M Health System's Department of Anesthesiology and pain specialist at U-M's Center for Interventional Pain Medicine. “The result of this disparity is that vulnerable populations are at increased risk for insufficient and lesser-quality pain care.

“For the pharmacies located in higher-income ZIP codes, those in white ZIP codes were more than 13 times more likely to have sufficient supplies than those in minority ZIP codes. When looking at those in lower-income ZIP codes, those in white ZIP codes were 54 times more likely than pharmacies in minority ZIP codes to have sufficient supplies.”

The statistics gathered during the U-M study corroborate something Green knows from her patients’ experiences. “I have patients who have to drive 30 miles or more just to get their pain medications,” Green says.

Most of the pharmacies met the study’s criteria for having sufficient opioid supply, which meant they had at least one drug in each of three categories: controlled release (such as controlled release oxycodone, controlled release morphine, fentanyl and levorphanol); short acting (such as immediate release oxycodone, immediate release morphine and hydromorphone); and combination products (such as acetaminophen and hydrocodone, aspirin and oxycodone, and acetaminophen and codeine).

But when comparing the number of pharmacies in white ZIP codes and minority ZIP codes that frequently stocked sufficient supplies of the medications, the gap was pronounced: 86.9 percent in white ZIP codes versus 54.2 percent in minority ZIP codes.

When asked about the insufficient supplies of these medications, the most common reason cited by pharmacists participating in the study in both white and minority areas was low demand (93.1 percent), which did not differ by racial composition or income. Green notes that the study did not delve into what “low demand” means, and she says future studies would be needed to shed light on this issue. The fear that patients might use opioid analgesics for illicit purposes was the second most common reason (8.5 percent), followed by too much paperwork and fear of robbery (about 1 percent each).

To the authors’ surprise, the study found that non-corporate pharmacies were more 24 times more likely to carry sufficient supplies of the medications than corporate pharmacies. Researchers also found that having a hospital near the pharmacy did not affect the availability of opioid analgesics.

Green believes that the new findings have important public health implications since people living in predominantly minority areas faced significant barriers to accessing pain medication, with greater disparities in low-income areas regardless of racial composition. Beyond minorities, these findings are particularly important for low-income people regardless of race, she notes.

The data are from pharmacies across the state of Michigan that were contacted between June 2003 and April 2004. Further studies will be needed to determine if the findings are true of the rest of the country.

In addition to Green, authors on the paper are S. Khady Ndao-Brumblay, M.Sc., Pharm.D., senior research associate in the Department of Anesthesiology; Brady West, M.A., senior statistician and statistical consultant with the Center for Statistical Consultation and Research, Office of the Vice President for Research at U-M; and Tamika Washington, research assistant, of the Department of Anesthesiology.

Funding was provided by the U-M Health System’s Department of Anesthesiology.