The Effect of Naltrexone on Memory Deficit Followed by Electroconvulsive Therapy: A Randomized, Double-Blind, Placebo-Controlled Trial

Electroconvulsive therapy (ECT) is famously known as a treatment for depression; however, memory impairments have always been a point of concern. The use of opioid antagonists may protect against the development of memory deficits after ECT. The current study aimed at assessing the effect of Naltrexone in diminishing memory impairments.
This randomized, double-blinded, placebo-controlled clinical trial took place at Imam Hossein hospital of Tehran/Iran. Patients diagnosed with MDD, were assigned to either Naltrexone or placebo and received 6 sessions of ECT within 2 weeks. Wechsler Memory Scale was performed the day before the first session of ECT, as well as 2 weeks, 1 and 3 months after finishing the 6th session. The Hamilton depression rating scale was performed 2 times to examine the possible interference caused by depression or to relapse as a confounding variable.
Patients receiving Naltrexone and placebo showed no significant difference in WMS scores. However, after further assessment, changes of WMS scores in every round were compared; the results showed that after 2 weeks from baseline, the amount of the reduction of total WMS scores from baseline was significantly lower in the Naltrexone group (P = 0.04).
This study suggests that Naltrexone as compared to placebo has no advantageous effect on attenuating memory deficits in the long term. It is a smaller degree of memory decline that makes Naltrexone superior to placebo.