Impact of childhood adversity on acute subjective effects of stimulant and opioid drugs: Evidence from placebo-controlled studies in healthy volunteers.

Background and aims: Early-life adversities are known to alter drug reward processing in rodents. Despite the well-known link between early adversity and the risk of substance use disorder, few studies have measured how childhood adversity affects human drug reward. Here, we assessed the relationship between historical childhood adversities and responses to single doses of methamphetamine, d-amphetamine or buprenorphine in healthy participants.

Methods: Using a secondary analysis approach, we assessed the impact of childhood adversity on drug effects from three randomised, placebo-controlled studies in which healthy volunteers received methamphetamine (20 mg oral; n = 35), d-amphetamine (20 mg oral; n = 54) or buprenorphine (0.2 mg sublingual; n = 35). Ratings of feeling effect, liking, disliking, feeling high and wanting more of the drug were collected 15-210 min post-administration, and heart rate changes were analysed using random-intercept mixed-effect models. The area under the curve from these and previous studies was calculated to visualise the relationship between childhood adversity severity and drug effects.

Results: Greater childhood adversity was associated with reduced feel effects (significant three-way interactions b = -0.07, 95% CI [-0.12, -0.02], p = 0.009), like effects (b = -0.07, 95% CI [-0.13, -0.00], p = 0.038) and feel high (b = -0.06, 95% CI [-0.10, -0.01], p = 0.020) towards the stimulant drugs 90-180 min post-administration.

Conclusions: Childhood adversity was not significantly associated with other subjective or heart rate responses to the drugs. Overall, participants with more childhood adversities reported dampened subjective responses to stimulant drugs, but not to buprenorphine. Future studies should examine the generalisability of these relationships, to identify the mechanisms underlying the link between childhood adversity and drug responsiveness.