Risk-Taking Propensity as a Predictor of Induction Onto Naltrexone Treatment for Opioid Dependence

Abstract

Heroin addiction is a chronic relapsing disorder that has devastating social, medical, and economic consequences. Naltrexone is an antagonist that blocks opioid effects and could be an effective medication for the treatment of opioid dependence. However, its clinical utility has been limited partly because of poor adherence and acceptability. Given the importance of compliance to naltrexone treatment for opioid dependence, the goal of the current study was to examine predictors involved in successful induction onto naltrexone treatment. Parametric and nonparametric statistical tests were performed on data from a sample of 64 individuals entering treatment who met DSM-IV criteria for opioid dependence. The relationship between naltrexone induction (ie, inducted vs not inducted onto naltrexone) and risk-taking propensity, as indexed by riskiness on the Balloon Analogue Risk Task (BART), was examined. Participants were recruited from local detoxification programs, inpatient drug treatment, and other Baltimore programs that provided services to opioid-dependent adults (eg, Baltimore Needle Exchange Program) during the period from August 2007 to September 2008. Positive association was shown between risk-taking propensity and odds of naltrexone induction. Specifically, each 5-point increase in the total BART score was associated with a 25% decrease in odds of naltrexone induction (OR = 0.76; 95% CI, 0.58-0.99; P = .041). This association remained statistically significant, even after adjusting for potential confounds, including injection drug use and cocaine positive urine results (P = .05). After adjusting for the covariates, each 5-point increase in BART score was associated with 28% decrease in the odds of achieving the maintenance dose (adjusted OR = 0.73; 95% CI, 0.54-0.99; P = .046). Risk-taking propensity was predictive of induction onto naltrexone treatment, above and beyond injection drug use and cocaine-positive urine samples.