Impulsiveness as a predictor of topiramate response for cocaine use disorder.

BACKGROUND/

OBJECTIVES

Topiramate has been studied in the treatment of substance use disorders and is often used off-label in the treatment of other disorders with impaired impulse control. We sought to determine whether impulsiveness could predict topiramate treatment response in individuals with cocaine use disorder (CUD).

METHODS

In a post-hoc analysis of a 12-week, double-blind, randomized, placebo-controlled trial of topiramate for CUD, we examined the relationship between response to treatment and participants' baseline score on the Barrett Impulsiveness Scale (BIS-11). During the original trial, topiramate was titrated up to 300 mg/day over 6 weeks and maintained for 6 weeks. All participants received weekly cognitive behavioral therapy.

RESULTS

Individuals with total BIS-11 scores above the median had 11.2% more cocaine-free days with topiramate versus placebo (Bonferroni corrected p = 0.047). Individuals with first-order factor scores above the median in self-control (Bonferroni corrected p = 0.020) and at or below the median in attention (Bonferroni corrected p = 0.022), and second-order factor scores at or below the median in attentional (Bonferroni corrected p = 0.024) and motor impulsiveness (Bonferroni corrected p = 0.046) were all associated with a greater improvement with topiramate.

DISCUSSION/

CONCLUSION

The results indicate an association between higher within-group impulsiveness and response to topiramate for CUD. The subscore findings may suggest a complex interaction between effectiveness and known cognitive side effects. The finding that trait impulsiveness is associated with treatment response is a promising discovery that may help guide treatment for CUD.

SCIENTIFIC SIGNIFICANCE: This analysis suggests a possible endophenotype based on impulsiveness that can predict treatment response to topiramate. (Am J Addict 2019;XX:1-6).