Private Equity Acquisition and Buprenorphine Prescribing.

Importance: Private equity investment in US health care, including substance use disorder treatment, has grown. However, the implications of private equity acquisition of substance use disorder treatment facilities for buprenorphine access and quality of care are unknown. Objective: To examine the associations of private equity acquisition of substance use disorder treatment facilities and buprenorphine prescribing patterns. Design, Setting, and Participants: In this cross-sectional study using difference-in-differences analysis, aggregate prescription claims from an analytical dataset for buprenorphine from acquired substance use disorder treatment facilities were compared with those from nonacquired facilities from 2019 quarter 3 through 2021 quarter 2. Prescriptions for buprenorphine filled by adult individuals (aged >18 years) were included in the analyses. An event study difference-in-differences design was used to assess changes in buprenorphine prescribing characteristics at facilities from 4 quarters before to 4 quarters after acquisition using a linear model adjusted for facility, year, and treatment cohort characteristics. Analyses were performed from January 2025 to December 2025. Main Outcomes and Measures: Patient volume, prescription volume, payer mix, and treatment retention duration. Results: In a sample of 90 acquired facilities and 2374 never-acquired facilities, private equity acquisition was associated with increases in patient volumes. Acquisition was associated with a mean increase of 65.66 (95% CI, 30.57-100.76; P < .001) patients receiving buprenorphine per facility quarter. Similarly, acquisition was associated with a mean increase of 163.90 (95% CI, 47.07-280.73; P = .006) buprenorphine prescriptions per facility quarter. Acquisition was associated with an increase of 0.73 (95% CI, 0.07-1.40; P = .03) percentage points in prescriptions paid with cash compared with the control group. Other payer types were not associated with acquisition. Measures of treatment episode duration decreased after acquisition, with decreases of 6.24 (95% CI, -11.47 to -1.00; P = .02) percentage points in 90-day retention and 7.91 (95% CI, -13.96 to -1.86; P = .01) percentage points in 180-day retention. Conclusion and Relevance: In this study, the volume of patients treated with buprenorphine increased after private equity acquisition, with minimal changes in the payer mix among these patients. However, the quality of treatment, in terms of buprenorphine retention duration, decreased after acquisition. These results underscore the need for oversight mechanisms and continued research to ensure incentives for private investment in addiction care align with delivery of high-quality evidence-based treatment.