Differences in prescription opioid analgesic availability: comparing minority and white pharmacies across Michigan

Little is known about physical barriers to adequate pain treatment for minorities. This investigation explored sociodemographic determinants of pain medication availability in Michigan pharmacies. A cross-sectional survey-based study with census data and data provided by Michigan community retail pharmacists was designed. Sufficient opioid analgesic supplies was defined as stocking at least one long-acting, short-acting, and combination opioid analgesic. Pharmacies located in minority (or=70% white residents) zip code areas were randomly selected by using a 2-stage sampling selection process (response rate, 80%). For the 190 pharmacies surveyed, most were located in white areas (51.6%) and had sufficient supplies (84.1%). After accounting for zip code median age and stratifying by income, pharmacies in white areas (odds ratio, 13.36 high income vs 54.42 low income) and noncorporate pharmacies (odds ratio, 24.92 high income vs 3.61 low income) were more likely to have sufficient opioid analgesic supplies (P < .005). Racial differences in the odds of having a sufficient supply were significantly higher in low income areas when compared with high income areas. Having a pharmacy located near a hospital did not change the availability for opioid analgesics. Persons living in predominantly minority areas experienced significant barriers to accessing pain medication, with greater disparities in low income areas regardless of ethnic composition. Differences were also found on the basis of pharmacy type, suggesting variability in pharmacist's decision making.

Michigan pharmacies in minority zip codes were 52 times less likely to carry sufficient opioid analgesics than pharmacies in white zip codes regardless of income. Lower income areas and corporate pharmacies were less likely to carry sufficient opioid analgesics. This study illustrates barriers to pain care and has public health implications.