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Methadone for opioid use disorder can be dispensed only from US Substance Abuse and Mental Health Services Administration (SAMHSA)–certified opioid treatment programs (OTPs), creating access barriers in rural counties with a shortage of facilities. Canada and Australia allow primary care prescribing and pharmacy dispensing of methadone to expand access.¹ Therefore, we examined drive times to the nearest OTP in urban and rural counties in 5 US states with the highest county rates of opioid-related overdose mortality.² In addition, we compared drive times to federally qualified health centers (FQHCs) as potential primary care methadone-prescribing locations and to dialysis centers as treatment locations for a different chronic disease requiring frequent engagement.

The outcome was the minimum drive time in minutes from the county mean center of population to the nearest OTP, FQHC, and dialysis center using the Esri ArcGIS rural drive-time tool (September 2017 version), which simulates automobile movement between 2 points along a national street network based on historical average speeds.³ From the 2010 US Census, we obtained the coordinates of the county mean center of population for all counties in Indiana, Kentucky, Ohio, Virginia, and West Virginia, excluding counties with geographic changes after the census. We geocoded 2017 OTP, FQHC, and dialysis center street addresses from the SAMHSA OTP Directory and the Health Resources and Services Administration data warehouse. Addresses not matched during batch geocoding were hand reviewed. We excluded school-based FQHCs and facilities remaining unmatched after hand review.

We stratified counties by the 2013 National Center for Health Statistics urban-rural county classification scheme, dividing counties into urban (large central metros, large fringe metros, medium metros, and small metros) and rural (micropolitan and noncore) levels (Table). We assessed the association across urban-rural classification using Welch analysis of variance. We used a paired t test to compare drive times to the nearest OTP with drive times to the nearest FQHC or dialysis center, using a Bonferroni correction for multiple comparisons. Hypothesis tests were 2-sided with α=.05. We completed our analyses in Stata 15 (StataCorp).

Of the 487 of 489 counties included, 270 (55.3%) were rural. Within the 5 states, 109 OTPs, 952 FQHCs, and 837 dialysis centers were included. Among all counties, the mean drive time to the nearest OTP was 37.3 (95% CI, 35.5-39.1) minutes and the mean drive time to the nearest OTP increased from 7.8 (95% CI, 5.7-9.9) minutes in the urban classification to 49.1 (95% CI, 46.3-51.8) minutes in the noncore rural classification (P &±ô³Ù; .001; Table). The mean drive time to the nearest FQHC was 15.8 (95% CI, 14.8-16.9) minutes (difference with OTP, 21.5 [95% CI, 19.5-23.4] minutes) and to the nearest dialysis center was 15.1 (95% CI, 14.1-16.2) minutes (difference with OTP, 22.1 [95% CI, 20.5-23.8] minutes). Longer drive times for OTPs vs FQHCs and dialysis centers were found for all urban-rural classifications (Figure) except large central metros, with the greatest difference in rural counties.

Rural county classification was associated with longer drive times to the nearest OTP compared with urban counties. Drive times to OTPs were longer than to FQHCs or dialysis centers. The greater geographic availability of hemodialysis, which requires engagement 3 times a week, contrasts with methadone treatment availability, for which federal law requires engagement 6 times a week for medication dispensing. Enabling FQHC methadone provision in the United States, mirroring practices in Canada and Australia, would expand geographic access without construction of additional facilities and may further integrate opioid use disorder treatment into primary care. An alternative path to improving access would be constructing new OTPs, as was done previously with dialysis centers whose access was expanded by the 1972 extension of Medicare disability coverage,⁴ although this would require significantly more investment in rural health care infrastructure. Limitations include that drive times were county-level population estimates, individual drive times within counties vary, and smaller geographic units would improve drive time estimation. County estimates are presented given the importance of local government approval of OTPs. The urban geographic availability of methadone was likely overestimated because of public transportation.

Accepted for Publication: August 1, 2019.

Corresponding Author: Paul J. Joudrey, MD, MPH, National Clinician Scholars Program, Yale School of Medicine, 333 Cedar St, Sterling Hall of Medicine IE-68, PO Box 208088, New Haven, CT 06520 (paul.joudrey@yale.edu).

Author Contributions: Dr Joudrey had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Joudrey, Wang.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Joudrey.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Joudrey.

Supervision: Wang.

Conflict of Interest Disclosures: None reported.

Funding/Support: Funding for this publication was provided by the Department of Veterans Affairs Office of Academic Affiliations through the National Clinician Scholars Program and by Clinical and Translational Science Award grant number TL1 TR001864 from the National Center for Advancing Translational Science and grant number 5K12DA033312 from the National Institute on Drug Abuse, both components of the National Institutes of Health (NIH).

Role of the Funder/Sponsor: The funders played no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript, and decision to submit the manuscript for publication.

Disclaimer: The contents are solely the responsibility of the authors and do not necessarily represent the official view of the NIH or the Department of Veterans Affairs.

Additional Contributions: We thank Miriam Olivares, MS, of Yale University for providing technical assistance with ArcGIS online. No compensation was provided for her contribution.