Assessing behavioural economic demand for morphine after an acute dose in individuals with- and without childhood...

Childhood trauma is associated with positive subjective responses to acute opioids in the laboratory. Yet, its impact on behavioural economic demand for opioids remains unclear. Because demand can predict future use and misuse, we investigated whether individuals with childhood trauma also display greater demand for opioids in the laboratory.

This secondary analysis used data from a double-blind, randomised, controlled, counterbalanced trial. Across two sessions, individuals with (n = 26) and without (n = 21) childhood trauma received a high (0.15 mg/kg) and low (0.01 mg/kg) dose of intramuscular morphine 120 min before a hypothetical purchase task. Participants also regularly reported their subjective desire for the study drug. Area under the consumption and expenditure curves, and specific demand indices (O_max, P_max, breakpoint, intensity, elasticity), were analysed with non-parametric mixed models.

Consumption and expenditure for low dose morphine was lower in the childhood trauma group when compared to high dose morphine in this group, and low dose morphine in the control group (ps ≤ 0.03). Consistent results were obtained for specific demand indices O_max, P_max, and breakpoint, but not intensity or elasticity. Positive correlations between subjective desire and consumption and expenditure were only observed in the childhood trauma group (Tau-c = 0.24-0.34, ps ≤ 0.03).

Under laboratory conditions, desires to use opioids among individuals with childhood traumas may not manifest in strong intentions to acquire these drugs. Diverging results from psychometric measures of subjective and economic opioid value highlight the need for future research to explore contextual and resilience factors to understand how problematic opioid use emerges after childhood traumas.