Estimates of geographic variation among states and counties in the prevalence of opioid prescribing are developed using data from a large (135 million) representative national sample of opioid prescriptions dispensed during 2008 by 37,000 retail pharmacies. Statistical analyses are used to estimate the extent to which county variation is explained by characteristics of resident populations, their healthcare utilization, proxy measures of morbidity, availability of healthcare resources, and prescription monitoring laws. Geographic variation in prevalence of prescribed opioids is large, greater than the variation observed for other healthcare services. Counties having the highest prescribing rates for opioids were disproportionately located in Appalachia and in southern and western states. The number of available physicians was by far the strongest predictor of amounts prescribed, but only one-third of county variation is explained by the combination of all measured factors. Wide variation in prescribing opioids reflects weak consensus regarding the appropriate use of opioids for treating pain, especially chronic noncancer pain. Patients' demands for treatment have increased, more potent opioids have become available, an epidemic of abuse has emerged, and calls for increased government regulation are growing. Greater guidance, education, and training in opioid prescribing are needed for clinicians to support appropriate prescribing practices. Wide geographic variation that does not reflect differences in the prevalence of injuries, surgeries, or conditions requiring analgesics raises questions about opioid prescribing practices. Low prescription rates may indicate undertreatment, while high rates may indicate overprescribing and insufficient attention to risks of misuse. Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.
