Drug test results as a predictor of retention among patients using buprenorphine in a comprehensive outpatient treatment program

ABSTRACT

The study examined the relationship between continued non-medical drug use and treatment retention for patients receiving buprenorphine maintenance treatment in a comprehensive addiction treatment program. The participants were 106 newly admitted patients and 103 continuing patients in treatment for an average of 9.4 months at the start of the study. Retrospective chart reviews were used to determine for each group whether the use of illicit, non-prescribed drugs during a 3-month baseline period was associated with lowered rates of treatment retention over the following 14 months. The New Admissions group was divided into 4 subgroups based on the percentage of urine drug tests that were positive during baseline: 0, 1–33, 34–67, or 68–100%. Because only 16 (15%) of the continuing patients had positive drug tests during baseline, the continuing group was divided into just 2 subgroups—no positives and any positives. Newly admitted patients testing positive for drugs more than 33% of the time were significantly more likely than those with less frequent or no positive tests to withdraw from treatment within 2 months. Continuing patients with at least 1 positive drug test left treatment 6 months sooner, on average, than those with no positive tests and were twice as likely to leave without completing continuing care (87 to 42%). Non-prescribed drug use during buprenorphine maintenance treatment is strongly correlated with lowered retention and risk of early treatment termination for new and continuing patients. Actions taken to monitor and reduce drug use during buprenorphine maintenance treatment may improve retention and enhance long-term recovery outcomes.

KEYWORDS:

• Buprenorphine
• opiate addiction
• opioid-related disorders
• opiate substitution treatment
• opioid substitution therapy
• drug addiction

Notes

I. The approach of requiring a minimum of three drug tests over a 3-month period to verify a pattern of abstinence or continued drug use is similar to one used in a recent study of retention in a methadone maintenance treatment program.²⁵

II. The absolute frequency of positive tests could not be used for these analyses since patients had anywhere from 3 to 15 tests during baseline. The percentage of tests that were positive for each individual was calculated by dividing the number of positives for illicit, non-prescribed drugs by the number of times the individual was tested and multiplying by 100.