A single ketamine infusion improved several treatment outcomes in adults with cocaine dependence who were engaged in mindfulness-based behavior modification, according to study data published in the American Journal of Psychiatry.
Individuals seeking treatment for cocaine dependence (n=55) were randomly assigned to receive a 40-minute intravenous infusion of either ketamine (0.5 mg/kg) or midazolam (0.025 mg/kg) as part of a five-week trial. Patients were hospitalized for five days in a psychiatric research unit, during which time they received daily sessions of mindfulness-based relapse prevention. On day 2, patients received their infusion; on day 5, they were discharged. Patients then attended twice-weekly follow-up visits for four weeks, at which they continued their sessions and were assessed for various clinical variables. Cocaine use after discharge was assessed via patient interview and urine toxicology screening. A six-month follow-up interview was also conducted by telephone.
Demographic and clinical variables were similar in patients who received ketamine (n=27) and patients who received midazolam (n=28). Route of cocaine ingestion was controlled for in all analyses. A total of 48.2% of patients in the ketamine group remained abstinent during the last two weeks of the trial compared with 10.7% of the midazolam group. The odds of end-of-study abstinence in the ketamine group was nearly six times that in the midazolam group (odds ratio, 5.7; 95% CI, 1.3-25.1; P =.02). Per Cox regression analysis, the ketamine group was 53% less likely to relapse compared with the midazolam group (hazard ratio, 0.47; 95% CI, 0.24-0.92; P =.03). In addition, craving scores were 58.1% lower in the ketamine group than in the midazolam group (P =.01). At the six-month telephone follow-up interview, 12 patients (44%) in the ketamine group reported abstinence compared with none in the midazolam group. The percentage of abstinent individuals was significantly associated with treatment group (P <.001).
A single ketamine infusion was associated with significantly improved treatment outcomes compared with midazolam in a cohort of adults with cocaine dependence. Further research in a larger sample is needed to confirm these findings.
Reference
Dakwar E, Nunes EV, Hart CL, et al. A single ketamine infusion combined with mindfulness-based behavioral modification to treat cocaine dependence: a randomized clinical trial [published online June 24, 2019]. Am J Psychiatry. doi:10.1176/appi.ajp.2019.18101123