Booth BM (CeMHOR, UAMS)
Mancino M (CeMHOR)
Han X (CeMHOR, UAMS)
Curran GM (CeMHOR, UAMS)
To identify demographic and clinical predictors of early attrition from methadone maintenance (MM). MM is a critical pharmacotherapy for treatment of opioid dependence to reduce HIV transmission and criminal behaviors, and improve functioning. Effectiveness of MM relies on retention, perhaps even years and research has documented substantial inter-VAMC variation in duration of MM.
VA national Outpatient Files for FY1999 were searched for new episodes of MM, defined as no previous visits with this stop code in the prior 60 days. Subsequent MM visits were traced through the end of FY2002, defining end of episode as no contact in the stop code for 60 days. VAMCs with < 25 patients were not included in the analysis. Survival analysis with proportional hazards regression examined predictors of duration in MM treatment, using time in MM as the dependent variable, with analysis accounting for the clustering effects of VAMCs. Independent variables included demographics, psychiatric and medical comorbidity.
We identified 2194 MM patients, 96% male, mean age of 48, 25% white, 47% African American, 6% Hispanic, and 22% “unknown” race. Overall, 48% had chart listed psychiatric diagnoses (in FY 1999), 34% major depression, 19% PTSD, 13% other anxiety disorders, 11% psychosis, and 9% bipolar disorder. The Charlson medical comorbidity index was an average of 1.5 (SD=1.9). Mean number of visits was 109 (SD=231) and 209 were still in MM by the end of FY2002. We found significant variation among VAMCs in average episode duration (range=8-443 visits, p < 0.001). Controlling for inter-VAMC variability, we found a significant interaction between age and time (p < 0.001), in that age was not significantly associated with shorter stays but younger age predicted attrition after the 25% percentile of visits. Compared to whites, African-Americans (hazard ratio 1.3), and unknown race (HR=1.7), and psychiatric comorbidity (HR=1.2) were significantly associated with shorter time in MM.
Interventions are important at the VAMC and individual patient level to assist veterans remain in MM. Further research needs to examine what characteristics of “race unknown” veterans are associated with poor retention in MM.
Retention in methadone maintenance is critical to reduce HIV transmission and criminal behavior in opioid dependent veterans.