An analysis of data from several previous studies indicated that individuals who experienced more childhood adversity tend to show dampened subjective responses to methamphetamine and d-amphetamine 90 to 180 minutes after administration. However, their subjective responses to buprenorphine were not affected, and this drug had little overall effect on the participants. The research was published in the Journal of Psychopharmacology.
Individuals with substance use problems often have a history of childhood abuse and neglect. Childhood abuse and neglect involve harmful behaviors or the failure to provide necessary care, leading to physical, emotional, or psychological harm. Abuse can be physical, emotional, or sexual, occurring when a child is deliberately mistreated or violated. Neglect, on the other hand, happens when a child’s basic needs, such as food, shelter, medical care, or emotional support, are not met.
Both abuse and neglect can have long-term effects on a child’s development, mental health, and ability to form relationships. These experiences often lead to trauma, which may result in anxiety, depression, or other difficulties in adulthood, including a higher propensity for substance use disorders.
Study author Molly Carlyle and her colleagues aimed to explore the impact of early life adversities on drug reward. In other words, they sought to determine whether childhood experiences of abuse and neglect influence how a person experiences drugs.
They analyzed data from existing randomized, placebo-controlled trials in which healthy adults received single doses of the psychoactive drugs methamphetamine, d-amphetamine, and buprenorphine. The first two are dopamine agonists, meaning they mimic the effects of the neurotransmitter dopamine in the brain. Buprenorphine is a partial opioid agonist, meaning it activates opioid receptors in the brain but produces a weaker response compared to full agonists.
The study authors analyzed data collected by the Human Behavioral Psychopharmacology Laboratory at the University of Chicago. This included three studies conducted on adults aged 18-40 who were recruited to participate in research involving drug administration. Study 1 involved 61 healthy participants receiving oral methamphetamine (20 mg). In the second study, 112 healthy adults received 20 mg of d-amphetamine, while the third study involved 38 participants receiving 0.2 mg of buprenorphine.
In all three studies, participants’ subjective responses to the drugs were assessed using the Drug Effects Questionnaire 90 to 180 minutes after administration. This questionnaire asks participants to rate how strongly they feel the effect of the drug, how high they are, how much they like or dislike the effects, and whether they would want more of the drug. Participants also completed an assessment of childhood adversity experiences using the Childhood Trauma Questionnaire.
The results showed that participants reporting higher levels of childhood adversity tended to report lower subjective effects of methamphetamine and d-amphetamine. These individuals reported feeling the drug effects less intensely, liking them less, and experiencing a lower drug-induced high. However, the degree to which participants disliked the drug or wanted more of it was not associated with reported childhood adversity.
Buprenorphine had little effect on participants overall. The effects of the dose used in the study were indistinguishable from placebo (when participants received a pill they believed contained the drug, but it did not). These effects, or the lack thereof, were not associated with reported childhood adversity.
“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,” the study authors concluded.
The study points to possible effects of childhood adversity on drug experiences. However, it should be noted that the study relied solely on self-reports. Therefore, it remains unclear whether individuals with childhood adversity experiences actually feel lower effects of stimulant drugs, or if they simply tend to report drug experiences differently, rating the same intensity of (pleasant) drug experiences as lower.
The paper, “Impact of childhood adversity on acute subjective effects of stimulant and opioid drugs: Evidence from placebo-controlled studies in healthy volunteers,” was authored by Molly Carlyle, Harriet de Wit, and Siri Leknes.
