County-Level Access to Opioid Use Disorder (OUD) Medications in Medicare Part-D (2010-2015)

The United States is facing a growing public health crisis as opioid-related overdose deaths continue to rise. Approximately 91 people a day are now dying from opioid overdoses. Concurrent with this rise in deaths are increasing rates of opioid use disorder (OUD) and admissions for OUD treatment. Central to addressing the opioid crisis is improving access to evidence-based medications for the treatment for OUD— methadone, buprenorphine and naltrexone. There are significant gaps in access to OUD medications across the United States. In 2012, there was an estimated OUD treatment gap of between 914,000 and 1.4 million, based on combined methadone and buprenorphine treatment capacity. This gap is due in part to the limited number and capacity of Opioid Treatment Programs (OTPs) as well as the geographic concentration of OTPs in urban areas, who are the sole providers of methadone in the US.

In an effort to expand access to OUD treatment medications beyond OTPs, the federal government passed the Drug Addiction Treatment Act of 2000 (DATA 2000). DATA 2000 allows physicians to obtain a waiver to prescribe buprenorphine outside of OTPs by completing an eight-hour training course. There are, however, limits on the number of patients a physician can treat with buprenorphine at one time. Physicians can treat up to 30 patients at one time in the first year they hold a waiver and can apply to prescribe buprenorphine to up to 100 and then 275 patients in subsequent years.

The current study improves upon prior research by examining access to buprenorphine and oral naltrexone among Medicare Part D enrollees at the county-level. No prior studies have examined access to oral naltrexone which is FDA approved for the treatment of relapse to opiates. In contrast to buprenorphine, naltrexone is not a scheduled narcotic and thus, can be prescribed by any physician. This study also identifies potential geographic disparities in access to OUD treatment medications, as well as county demographic and economic characteristics associated with access to buprenorphine and oral naltrexone prescribers in Medicare Part D.