State X-Waiver Statutes and Buprenorphine Prescriber Rates After Federal X-Waiver Elimination, 2021-2023

Area of Science:

• Public Health
• Health Policy
• Substance Use Disorder Treatment

Background:

• Federal elimination of the X-waiver aimed to increase buprenorphine access for opioid use disorder (OUD).
• Some U.S. jurisdictions maintained X-waiver-related language in their statutes post-elimination.
• The impact of retaining these statutory elements on buprenorphine prescriber rates remains unclear.

Purpose of the Study:

• To investigate if U.S. jurisdictions that kept X-waiver elements in statutes had lower buprenorphine prescriber rates compared to those that did not.
• To assess the association between state-level X-waiver retention and buprenorphine prescriber density.

Main Methods:

• Utilized a 25% random sample of IQVIA PharMetrics® Plus data (January 2021-October 2023).
• Employed Comparative Interrupted Time Series (CITS) models and generalized estimating equations (GEE) to analyze monthly prescriber rates per 10,000 eligible prescribers.
• Classified jurisdictions based on the presence of X-waiver language in statutes, adjusting for OUD diagnosis rates and overdose mortality.

Main Results:

• Included 49 jurisdictions and 1,558 jurisdiction-months in the analysis.
• Initially, mean buprenorphine prescriber rates were higher in jurisdictions with X-waiver references (96.84/10,000) versus without (47.01/10,000).
• No statistically significant difference in the level or trend of buprenorphine prescribers was observed between jurisdictions with and without X-waiver references post-elimination (p > 0.131).

Conclusions:

• Removing jurisdiction-level statutory X-waiver references appears unlikely to significantly expand buprenorphine prescribing.
• Persistent structural barriers, beyond state-level statutory language, may impede broader access to buprenorphine for OUD treatment.
• Findings were robust across provider types and sensitivity analyses.