摘要：Nonmedical prescription opioid misuse remains a growing public problem in need of action and is concentrated in areas of US states with large rural populations such as Kentucky, West Virginia, Alaska, and Oklahoma. We developed hypotheses regarding the influence of 4 factors: (1) greater opioid prescription in rural areas, creating availability from which illegal markets can arise; (2) an out-migration of young adults; (3) greater rural social and kinship network connections, which may facilitate drug diversion and distribution; and (4) economic stressors that may create vulnerability to drug use more generally. A systematic consideration of the contexts that create differences in availability, access, and preferences is critical to understanding how drug use context varies across geography. Nonmedical prescription opioid use is a rapidly escalating public health problem. Unintentional overdose deaths from opioid pain relievers has quadrupled since 1999 and by 2007 outnumbered those involving heroin and cocaine combined. 1 Much of this growth has been because of an increased misuse of opioid analgesics, which contributed to 21% of all poisoning deaths in 1999 and 37% in 2006. 2 By 2010, 2.4 million Americans initiated nonmedical prescription opioid use; this equals 6600 daily initiates. 3 Other evidence demonstrates a sharp increase in rates of use of prescription opioids 4,5 abuse or dependence, 4 emergency department visits, 6,7 and overdose injury among all age groups in the United States. 8–10 Although all states have demonstrated an increase in nonmedical prescription opioid morbidity and mortality during the past decade, death and injury from nonmedical prescription opioid misuse are concentrated in states with large rural populations, such as Kentucky, West Virginia, Alaska, and Oklahoma. 11–13 Distinctions between urban and rural areas are not binary but reflect a continuum of population density and proximity to the 1098 defined metropolitan areas of the United States. 14 We conceptualized rural areas as nonmetropolitan counties, acknowledging that this is a heterogeneous category for geographical areas. Individuals in counties outside metropolitan areas have higher rates of drug poisoning deaths, including deaths from opioids, and opioid poisonings in nonmetropolitan counties have increased at a rate greater than threefold the increase in metropolitan counties. 11 Drug-related deaths involving opioid analgesics are higher in these rural areas even after adjusting for population density, 15 and the ratio of nonmedical users to medical users is higher in rural areas as well. 16 Nationally representative surveys have indicated that, in rural areas, not only are there higher mortality and injury rates but also adolescents are more likely to use prescription opioids nonmedically than are their urban counterparts. 17–20 These surveys also report that factors such as polydrug use and depression are associated with nonmedical opioid use in rural areas. 20 Why is nonmedical prescription opioid misuse more prevalent in rural areas than in urban areas? There is, surprisingly, little empirical data that help us address this question. Risk factors that explain rural–urban differences in nonmedical prescription opioid use must vary across rural versus urban geographical contexts and be either associated with drug use generally or use of nonmedical prescription opioids specifically. Although contextual determinants of drug use are important in explaining why individuals use drugs and become dependent, 21,22 our understanding of the mechanisms through which broadly defined geographical settings influence drug use remains limited. We approached this issue in 3 steps. First, we explicated an array of known risk factors associated with illicit drug use generally. Second, we considered whether any of these factors are associated specifically with nonmedical prescription opioid use. Third, we linked the factors to the rural context, providing hypotheses that may explain the excess burden of prescription opioid misuse in rural compared with urban areas.
