Association between Comprehensive Primary Care Plus and opioid prescribing and prescription fills among Medicare beneficiaries.

Introduction: To examine if Medicare beneficiaries attributed to Comprehensive Primary Care Plus (CPC+) practices had a greater decrease in the potential overuse of prescription opioids relative to beneficiaries attributed to other primary care practices. Primary care practices that participated in CPC+ received enhanced Medicare payment to support five functions: access and continuity of care, care management, comprehensiveness and coordination, patient and caregiver engagement, and planned care and population health. CPC+ practices participated within two tracks starting in 2017; Track 2 practices received larger payments to support more enhanced care delivery than Track 1 practices.

Methods: Employing difference-in-differences, we used Medicare claims and Part D data to examine changes in potential opioid overuse between 2016 (baseline) and 2021 (the fifth program year). Our measure of potential opioid overuse measure relies on specifications for an existing quality measure of the same name that is defined as filling opioid prescriptions at a daily dosage of 90 morphine milligram equivalents or more among beneficiaries who use opioids for at least 90 days of supply per year. A total of 40,219 Medicare fee-for-service beneficiaries used opioids long term and were attributed to 2888 CPC+ practices; 129,178 beneficiaries used opioids long term and were attributed to 6921 comparison practices.

Results: Across the combined treatment and comparison groups, potential opioid overuse decreased from 19 % in 2016 to 12 % in 2021. Relative to the comparison group, beneficiaries attributed to Track 1 CPC+ practices experienced an 0.8 percentage point greater decrease in potential opioid overuse (95 % CI = -1.4, -0.2) in the third program year compared to baseline. These findings persisted in the fourth and fifth years and were similar in magnitude to those in the third year. Track 2 results were similar to Track 1 results. The findings were likely driven by changes in CPC+ clinicians' prescribing behaviors: clinicians in CPC+ practices reduced the average dosage and the number of days' supply of prescription opioids more than clinicians in comparison practices.

Conclusions: A large-scale primary care delivery transformation initiative was associated with reduced potential opioid overuse among Medicare beneficiaries.