Comparative outcomes of VA office-based buprenorphine and methadone treatment for opioid dependence in the VA

Broyles LM, Hanusa BH, Krumm M, Paidisetty S, Forman SD. Comparative outcomes of VA office-based buprenorphine and methadone treatment for opioid dependence in the VA. Paper presented at: VA Implementing a Public Health Model for Meeting the Mental Health Needs of Veterans Annual Mental Health Conference; 2010 Jul 28; Baltimore, MD.

Background: In the Veterans Health Administration (VHA), opioid agonist therapy (OAT) in the form of methadone (M-OAT) is available at 42 VHA facilities and another 10 facilities contract M-OAT care to non-VA, community based facilities. Access to VHA office-based buprenorphine OAT (B-OAT) is increasingly available and has been shown to be effective at reducing illicit drug use, increasing retention into treatment, and improving social and medical outcomes. Encouraging Veteran patients access to any OAT care is mandated by the UMHS Handbook and encouraging implementation of B-OAT care throughout the VHA can improve access to care to Veterans who are unwilling or unable to access VHA M-OAT care. However, it is unclear in VA settings-and particularly in settings where both VHA M-OAT and B-OAT are available-whether B-OAT treatment engages patients who are different than those who are traditionally served by VHA M-OAT facilities and what differences in treatment outcomes appear between VHA M-OAT and B-OAT care. In this study, we sought to compare Veteran patients' characteristics upon entry into B-OAT and M-OAT care at one VHA facility and evaluate and compare patient-level outcomes to B-OAT and M-OAT treatment. Methods and Results: We conducted a retrospective chart review of all patients receiving OAT within a VHA facility with dual patient access to M-OAT and B-OAT care from January 1, 2003 through January 1, 2007. We compared patient characteristics of those who initiated maintenance M-OAT and B-OAT, evaluated trends in use over time, and assessed differences based on provider type. We then examined the patient-level outcomes of patients enrolled in maintenance M-OAT and B-OAT care over time. We examined death, time to death, and retention (length of treatment). Of the 111 Veteran patients who were enrolled in OAT, B-OAT patients (n = 58) compared to M-OAT patients (n = 53), were less likely to have an infectious disease (p = .006), hepatitis C (p = .003), and use marijuana (p = .001). B-OAT patients were more likely to have anxiety (p = .022) and be attempting rehabilitation for the first time (p = .002). Significant differences in patient characteristics were found between B-OAT provided by primary care or mental health providers, with mental health providers prescribing B-OAT to patients whose characteristics were more similar to M-OAT patients. The proportion of patients receiving B-OAT treatment increased over time while patients receiving M-OAT reduced over time (p < 0.001). In the sample, there were at total of 12 (10.8%) deaths [8 (15.1%) in M-OAT, 4 (6.9%) in B-OAT, Fisher's Exact Statistic, p = 0.50)]. Time to death among the groups was also equivalent (Mantel-Cox, 2 = 1.04, p = 0.31). Veterans treated with B-OAT by their PCPs were more likely to discontinue treatment than those treated with B-OAT by psychiatrists or M-OAT (Fisher's Exact Statistic, p = 0.015). Median times on treatment (truncated at 4 years) varied from 829 days for Veterans treated with B-OAT by primary care providers to 1034 days for Veterans treated with B-OAT by psychiatrists to 1470 days for Veterans treated with M-OAT (Kruskal-Wallace 2 = 21.25, p < 0.001). When analyzed as time to stopping treatment, Veterans treated with B-OAT by primary care providers spent less time on treatment than Veterans treated the psychiatrists (Mantel-Cox, 2 = 13.77, p = 0.001). Conclusions: At a VHA facility where Veteran patients had dual access to both M-OAT and B-OAT care, patient characteristics differed upon enrollment into maintenance treatment and by the type of provider initiating B-OAT. Patient-level outcomes were similar between M-OAT and B-OAT care, but differed primarily based on treating provider type.